High Dosage Mucoadhesive Metronidazole Aqueous-based Gel Formulations Their Use To Treat

  • Published: Oct 26, 2017
  • Family: 21
  • Cited Works: 0
  • Cited by: 0
  • Cites: 5
  • Additional Info: Full text
This following text has been automatically extracted from the original PDF supplied by the patent office.  Please refer to the original PDF document to view the text in its original format.
AU 2016200825 B2
(12) STANDARD PATENT (11) Application No. AU 2016200825 B2 
(19) AUSTRALIAN PATENT OFFICE 
(54) Title 
High dosage mucoadhesive metronidazole aqueous-based gel formulations their use 
to treat 
(51) International Patent Classification(s) 
A61K 31/415 (2006.01) A01N 43/50 (2006.01) 
(21) Application No: 2016200825 (22) Date of Filing: 2016.02.09 
(43) Publication Date: 2016.03.03 
(43) Publication Journal Date: 2016.03.03 
(44) Accepted Journal Date: 2017.10.26 
(62) Divisional of: 
2012275292 
(71) Applicant(s) 
CHEMO RESEARCH, S.L.  
(72) Inventor(s) 
NORDSIEK, Michael T.;BALAJI, Kodumudi S.  
(74) Agent / Attorney 
FB Rice Pty Ltd, L 14 90 Collins St, Melbourne, VIC, 3000, AU 
(56) Related Art 
US 2010/0048645 Al 
US 2005/0080038 Al 
US 2009/0030060 Al 
WO 2009/097143 Al 
US 2006/0093675 Al

ABSTRACT 
The present disclosure relates to mucoadhesive aqueous-based homogenous gel formulations 
of metronidazole (MTZ) for intravaginal application and their uses, for example to treat 
bacterial vaginosis. Particular compositions comprise high concentration, high dosage, 1% to 
2% by weight formulations providing 60mg-Omg MTZ in a single application. These 
compositions also reduce the incidence of vulvovaginal candidiasis, which is a common 
occurrence following treatment for bacterial vaginosis. Compositions also comprise 
mucoadhesive gelling polymers and a solvent system comprising lower aromatic alcohols, 
lower alkylene diols and polyoxyalkeylenes, wherein the formulation can be free from 
solubility enhancers such as dextrins, cyclodextrins, niacin, niacinamide and surfactants.

HIGH DOSAGE MUCOADHESIVE METRONIDAZOLE AQUEOUS-BASED GEL 
FORMULATIONS AND THEIR USE TO TREAT BACTERIAL VAGINOSIS 
1. CROSS REFERENCE TO RELATED APPLICATIONS 
[0001] The present application is a divisional of AU 2012275292, the entire contents of which are 
incorporated herein by reference. This application claims the benefit of U.S. Provisional Application 
No. 61/502,285, filed June 28, 2011 and U.S. Provisional Application No. 61/508,058, filed July 14, 
2011, the contents of which are incorporated herein by reference in their entireties. This application is 
also related to U.S. Provisional Application No. 61/502,288, filed June 28, 2011 and U.S. Provisional 
Application No. 61/508,054, filed July 14, 2011, the contents of which are incorporated herein by 
reference in their entireties.  
2. FIELD 
[00021 The present disclosure relates to aqueous-based gel formulations of metronidazole and their 
uses, for example to treat bacterial vaginosis.  
3. BACKGROUND 
[00031 Bacterial vaginosis (hereafter "BV") is reported to be the most common cause of vaginitis 
found in women of reproductive age, causing 40-50% of all vaginal infections (Sobel, 1997, "Review 
Article: Vaginitis," New Engl J Med 337:1896-1903). BV can cause bothersome symptoms, and can 
at times increase the risk of acquiring sexually transmitted diseases, such as HIV. BV is thought to 
represent a synergistic polymicrobial bacterial infection characterized by an overgrowth (100x 
1 000x) of bacterial species often found as part of normal vaginal microflora, including Gardnerella 
vaginalis, Bacteroides spp. (some now classified as Prevotella spp.), anaerobic Gram-positive cocci, 
Mobiluncus spp. and Mycoplasma hominis. Accompanying this increase is a marked decrease in 
Lactobacillus species normally present that are believed to regulate the growth of other vaginal flora.  
Moreover, hydrogen peroxide-producing strains of Lactobacillus that dominate the vaginal flora of 
healthy women are replaced by non-hydrogen peroxide-producing strains in women with BV (Amsel 
et al., 1983, Am J. Med 74:14; Sobel et al, 1990, Infect Med May:24). Generally, studies show that 
there are greater quantitative than qualitative differences in the vaginal micro flora of women with 
BV as compared to healthy women, indicating that some of the clinical signs and symptoms of BV 
may be related to quantitative differences in one or more naturally present microbial species (Masfari 
et al., 1986, Genitourin Med 62:256). The factors responsible for the initial disruption of, and

eventual change in, the balance of species in the vaginal ecosystem are not well understood, and the 
exact locus of the infection is unknown, complicating efforts for developing suitable treatments.  
[0004] Metronidazole, approved by the FDA on July 18, 1963, and clindamycin are two of the oldest 
and most commonly used antibiotics that are prescribed to treat women who suffer from and/or are 
diagnosed with BV ((CDC 2006 STD Treatment Guidelines MMWR 2006; 55 (No. RR-7)).  
[0005] Metronidazole is available from numerous sources as oral tablets and capsules, injectable 
solutions, 0.75 wt% topical lotions, creams and gels, 1.0 wt% topical gels and 0.75 wt% vaginal gels.  
The topical creams, lotions and gels are generally indicated for the treatment or rosacea, wherein the 
vaginal gels, for example the 0.75 wt% metronidazole vaginal gel sold by Medicis under the brand 
name METROGEL VAGINAL@, are indicated for the treatment of BV.  
[0006] Despite their common use, treatment with the 0.75 wt% vaginal metronidazole gels such as 
METROGEL VAGINAL@ are less than ideal. To be effective, the gels must be applied once or 
twice a day for a period of five days.  
[0007] Moreover, recurrence of BV is commonly observed in up to 30% of women within three 
months of treatment, whether oral or vaginal. The reasons for recurrence remain unclear. See, e.g., 
Larsson, 1992, Int J Std Aids 3:239-247; Wilson, 2004, Sex Transm Infect 80:8-11. It has been 
shown in a double-blind, placebo-controlled crossover trial that intravaginal treatment with a 0.75% 
metronidazole gel resulted in a recurrence rate of about 15% one month following treatment. See, 
Hillier et al., Jun 1993, "Efficacy of Intravaginal 0.75% Metronidazole Gel for the Treatment of 
Bacterial Vaginosis," Obstet Gynecol 81(6):963-967. Vulvovaginal candidiasis, commonly known 
as a yeast infection, is also observed in approximately 10% of women following treatment for BV.  
[0008] In view of the fact that BV is currently the most prevalent form of vaginal infection in women 
of reproductive age, there is a real and immediate need for new therapies that address one or more of 
the shortcomings of currently available BV treatments. For example, it would be desirable to have 
available an intravaginal treatment that provides an effective cure in a single application, and/or that 
provides a more effective cure than currently available 0.75 wt% intravaginal metronidazole gels, 
reduces the rate of recurrence of BV following a successful course of treatment, and/or reduces the 
incidence of vulvovaginal candidiasis following a successful course of BV treatment.

4. SUMMARY 
[0009] It has been surprisingly discovered that formulating metronidazole ("MTZ") in mucoadhesive 
aqueous-based gel vehicles at concentrations higher than those currently employed to treat bacterial 
vaginosis ("BV") yields treatments that overcome several of the shortcomings of current intravaginal 
BV treatments such as METROGEL VAGINAL@. For example, as will be discussed in more detail 
below, "high dosage" mucoadhesive MTZ aqueous-based gels comprising about 1-2% by weight 
("wt%") of MTZ surprisingly deliver significantly higher than expected local concentrations of MTZ, 
and significantly higher local concentrations of MTZ than are delivered by a 0.75 wt% MTZ gel 
similar to METROGEL VAGINAL@ in in vitro skin permeation experiments carried out with human 
cadaver skin. When used to treat women suffering from and/or diagnosed with BV, an embodiment 
of the high dosage mucoadhesive aqueous-based gels comprising 1.3 wt% MTZ yielded superior 
results as compared to METROGEL VAGINAL®. For example, when applied once daily for a 
period of three days, the efficacy achieved with the 1.3 wt% high dosage MTZ gel of the instant 
disclosure was about the same as that achieved in women treated with the currently available FDA
approved 0.75 wt% MTZ gels in accordance with their standard 5-day treatment regimen. Quite 
surprisingly, a single application of the high dosage 1.3 wt% MTZ gel of the instant disclosure was 
found to be as effective as a course of 0.75 wt% MTZ gel applied once a day for a period of five days.  
This discovery is significant, as it provides for effective treatment of BV with exposure to far less 
total MTZ, reducing the risk of untoward and even dangerous side effects.  
[0010] While not intending to be bound by any theory of operation, it is believed that the surprising 
efficacy of the exemplary 1.3 wt% MTZ aqueous-based gel may be due, in part, to the above
mentioned unexpectedly high levels of MTZ released locally by the novel mucoadhesive aqueous
based gels described herein.  
[00111 It has also been surprisingly discovered that when the 1.3 wt% MTZ high dosage gel is 
applied once daily to a vagina of a woman suffering from and/or diagnosed with BV for a period of 
five days, the efficacy is dramatically increased as compared to METROGEL VAGINAL®, as 
determined by, for example, any one of increased cure rates, increased time to resolution of 
symptoms, increased time to recurrence of symptoms, and/or decreased incidence of recurrence.  
Thus, it has been surprisingly discovered that when a high dosage mucoadhesive MTZ aqueous-based 
gel is applied once daily to the vagina of a woman who suffers from and/or is diagnosed with BV for 
a period of five days, the efficacy achieved is far superior to, and the incidence of BV recurrence

remarkably reduced, as compared to women treated with the currently available FDA-approved 
0.75% metronidazole gels in accordance with their standard 5-day treatment regimen.  
[0012] Moreover, women suffering from and/or diagnosed with BV treated with the high dosage 
1.3 wt% MTZ formulation described herein for a period of five days exhibited another unexpected 
and remarkable result - virtually no incidence of post-treatment vulvovaginal candidiasis. To the 
knowledge of the Applicants, this result is unprecedented.  
[0013] Accordingly, in one aspect, the present disclosure provides novel "high dosage" 
mucoadhesive MTZ aqueous-based gels that can be applied topically, and in particular intravaginally 
to a woman, to treat, among other things, BV. The high dosage mucoadhesive MTZ aqueous-based 
gels generally comprise about 1% to about 2% by weight MTZ, in some specific embodiments, about 
1.0%, about 1.1%, about 1.2%, about 1.3%, about 1.4%, about 1.5%, about 1.6%, about 1.7%, about 
1.8%, about 1.9%, or about 2.0% by weight MTZ, and one or more gelling polymers and/or agents.  
The MTZ can be included in the gels in the form of a free base or a salt, such as a salt formed with a 
pharmaceutically acceptable acid.  
[0014] The gels typically include a total quantity of gelling polymer(s) sufficient to yield a viscosity 
in the range of about 200,000 - 400,000 mPa at 25 'C, for example about 250,000 - 350,000 mPa at 
'C, using the controlled shear rate ramp method, a Bholin CVO 100 rheometer and the rheometer 
settings provided in Table 11, infra. Depending upon the specific gelling polymer(s) and gelling 
conditions used, aqueous-based gels having viscosities in this range are generally achieved by 
including in the gels a total quantity of gelling polymer(s) ranging from about 0.5% to about 5% by 
weight. In some specific embodiments, the high dosage mucoadhesive MTZ aqueous-based gels 
described herein will include about 1% to about 3% by weight total gelling polymer(s), and in some 
specific embodiments about 2% by weight total gelling polymer(s).  
[00151 Skilled artisans will appreciate that different gelling polymers exhibit different degrees of 
mucoadhesion. For gels designed for intravaginal application to treat BV, the gelling polymers can 
be mucoadhesive. The specific mucoadhesive gelling polymer(s) selected are not critical for success 
and can be selected from amongst any mucoadhesive polymers capable of forming gels in aqueous
based solutions. Exemplary suitable mucoadhesive gelling polymers are described in more detail in 
the Detailed Description section. All of these mucoadhesive gelling polymers can be used singly or 
in combinations.

[00161 Generally, mucoadhesive gelling polymers should be selected such that, when used to make 
an aqueous-based gel having a viscosity in the range described above, yield a gel exhibiting a degree 
of mucoadhesion that is within about ±10% of that observed with exemplary high dosage 
mucoadhesive MTZ aqueous-based gel MG33PB under the same assay conditions. In a specific 
exemplary embodiment, the mucoadhesive polymer(s) are selected from the group consisting of a 
hydroxyalkyl cellulose, a carbomer, a polycarbophil and mixtures thereof. In another specific 
exemplary embodiment, the mucoadbesive polymer(s) is a polycarbophil.  
[0017] Skilled artisans will appreciate that while in many embodiments the one or more gelling 
polymer will have mucoadhesive characteristics, it need not. Polymers capable of forming gels in 
aqueous-based solutions that do not have mucoadhesive properties, or that yield an insufficient degree 
of mucoadhesion, can be used in combination with mucoadhesive agents, whether gel-forming or not, 
to yield high dosage mucoadhesive MTZ aqueous-based gels as described herein.  
[0018] The high dosage mucoadhesive MTZ aqueous-based gels also comprise a solvent system for 
the MTZ. It is well-known that MTZ presents solubility problems when attempting to formulate gels 
useful for topical and vaginal administration with excipients approved by the FDA for use in humans.  
Others have attempted to solubilize MTZ in aqueous solutions at concentrations of greater than 0.75% 
or 1.0% by weight. For example, U.S. Patent No. 6,881,726 describes the use of cyclodextrin and 
beta-cyclodextrin to enhance the solubility of MTZ in aqueous-based solutions. U.S. Patent No.  
7,348,317 describes the additional use of niacin and niacinamide to enhance the solubility of MTZ in 
aqueous-based solutions. Still others have attempted to increase the concentration of MTZ in 
aqueous-based solutions using surfactants. Any of these solvent systems can be used to solubilize the 
MTZ to the desired concentration in the high dosage mucoadhesive MTZ aqueous-based gels 
described herein.  
[00191 Although solubility enhancing agents can be used, it has been surprisingly discovered that 
MTZ can be solubilized at concentrations sufficient to yield high dosage mucoadhesive MTZ 
aqueous-based gels containing about 1% to about 2% by weight MTZ without having to use solubility 
enhancing compounds, such as those described above. This is advantageous, because agents such as 
cyclodextrins and beta-cyclodextrins in many instances enhance the water-solubility of compounds by 
forming complexes, yielding complex formulations where the compound is not uniformly dissolved 
in the formulation, agents such as niacin and niacinamide may themselves have undesired

pharmacological properties at certain concentrations, and agents such as surfactants can cause gels to 
be multiphasic.  
[0020] Accordingly, also provided is a novel solvent system useful for preparing high dosage MTZ 
gels as described herein. The novel solvent system yields high dosage mucoadhesive MTZ aqueous
based gels that are homogeneous, i.e., the MTZ is dissolved in the gel, and that are shelf-stable for 
long periods of time, such as six months or more, when stored at a temperature in the range of about 
0C to about 40 'C. Indeed, a specific exemplary embodiment of a high dosage mucoadhesive MTZ 
aqueous-based gel comprising 1.3 wt% MTZ has been found to be stable for a period of at least 18 
months when stored at temperatures of 25 'C and 40 'C.  
[0021] The novel solvent system generally utilizes one or more solvents that collectively have a 
saturated MTZ solubility at 25 'C that is sufficient to yield a gel containing the desired concentration 
of MTZ. Generally, such solvents will each have a saturated MTZ solubility at 25 'C of at least about 
mg/g, although skilled artisans will appreciate that when solvents are selected that have 
appreciably higher saturated MTZ solubilities, the novel solvent system may include solvents with 
lower saturated MTZ solubilities. A non-limiting list of solvents having suitable saturated MTZ 
solubilities that may be used as components of the novel solvent system are provided in the Examples 
section.  
[00221 Certain classes of solvents have been discovered to have saturated MTZ solubilities at 25 'C 
of at least about 20 mg/g. For example, it has been discovered that certain alcohols, for example 
lower aliphatic alcohols such as ethanol and lower aromatic alcohols such as benzyl alcohol, certain 
diols, such as, for example lower aliphatic diols (including, for example, lower aliphatic glycols such 
as ethylene glycol and propylene glycol) and certain polyethers, such as, for example, 
polyoxyalkylenes having molecular weights in the range of about 200 to about 600 ("lower 
polyoxyalkylene") (including, for example, PEG 400) have saturated MTZ solubilities at 25 'C in this 
range. Indeed, certain lower aromatic alcohols have significantly higher saturated MTZ solubilities at 
'C, for example, at least about 50 mg/g. As a specific example, benzyl alcohol has a saturated 
MTZ solubility of about 72 mg/g at 25 'C. All of these solvents and others having saturated MTZ 
solubilities at 25 'C of at least about 20 mg/g can be used alone and in various combinations in the 
novel solvent systems to solubilize MTZ in the high dosage mucoadhesive MTZ aqueous-based gels 
described herein.

[0023] In some embodiments, the novel solvent system comprises at least one solvent having a 
saturated MTZ solubility at 25 *C of at least about 50 mg/g and optionally one or more solvents 
having a saturated MTZ solubility at 25 *C of at least about 20 mg/g. In some embodiments, the 
novel solvent system comprises at least one solvent having a saturated MTZ solubility at 25 'C of at 
least about 50 mg/g and one or more solvents that collectively have a saturated MTZ solubility at 
'C of at least about 20 mg/g. In some specific embodiments, each of the solvents has a saturated 
MTZ solubility at 25 'C of at least about 20 mg/g.  
[0024] In some specific embodiments, the novel solvent system comprises from about 1 wt% to 
about 5 wt% of the at least one solvent having a saturated MTZ solubility at 25 *C of at least about 
mg/ml, with the remaining about 95 wt% to about 99 wt% being composed of the one or more 
solvents that collectively have a saturated MTZ solubility at 25 'C of at least about 20 mg/ml. In 
some specific embodiments, the solvent system comprises about 1.0 wt%, about 1.5 wt%, about 
2.0 wt%, about 2.5 wt%, about 3.0 wt%, about 3.5 wt%, about 4.0 wt%, about 4.5 wt% or about 
5.0 wt% (or any range bracketed by any of these values) of the at least one solvent having a saturated 
MTZ solubility at 25 'C of at least about 50 mg/ml and the remainder being composed of the one or 
more solvents that collectively have a saturated MTZ solubility at 25 'C of at least about 20 mg/ml.  
[0025] It has been discovered that ternary solvent systems utilizing one or more lower aromatic 
alcohols; one or more lower aliphatic diols; and one or more lower polyoxyalkylenes yield good 
results. Accordingly, in some specific embodiments, the high dosage mucoadhesive MTZ aqueous
based gels described herein utilize a novel solvent system for MTZ that comprises one or more lower 
aromatic alcohols, one or more lower aliphatic diols and one or more lower polyoxyalkylenes.  
[0026] In some specific embodiments, the solvent systems described herein do not include, or are 
substantially free of, other agents known to enhance the solubility of MTZ in aqueous-based 
solutions, such as cyclodextrins, beta-cyclodextrins, niacin, niacinamide and/or surfactants. In some 
specific embodiments, the solvent system is a ternary solvent system that consists only of one or more 
lower aromatic alcohol(s), one or more the lower alkylene diol(s) and one or more polyoxyalkylene(s) 
and does not include any other additional agents or solvents.  
[0027] The one or more lower aromatic alcohol can be a phenolic, primary, secondary or tertiary 
alcohol, and therefore may include aliphatic or heteroaliphatic groups in addition to an aromatic 
group. The one or more lower aliphatic diols and lower polyoxyalkylenes can be saturated or

unsaturated and can include primary, secondary and/or tertiary alcohol groups. Exemplary lower 
aromatic alcohols, lower aliphatic diols and lower polyoxyalkylenes useful in this specific 
embodiment of the novel solvent system and high dosage mucoadhesive MTZ aqueous-based gels 
described herein are described in more detail in the Detailed Description section. In some specific 
embodiments, the one or more lower aromatic alcohol is benzyl alcohol, the one or more lower 
aliphatic diol is propane-1,2-diol (propylene glycol) and the one or more lower polyoxyalkylene is 
polyethylene glycol having a MW of about 400 (PEG 400).  
[00281 In some specific embodiments, the solvent system comprises about 3.5% to about 5% by 
weight total lower aromatic alcohol(s) and about 95% to about 96.5% by weight total lower aliphatic 
diol(s), about 95% to about 96.5% by weight total lower polyoxyalkylene(s) or about 95% to about 
96.5% by weight of a mixture of total lower aliphatic diol(s) and total lower polyoxyalkylene(s).  
When mixtures are used, the weight ratio of total lower aliphatic diol(s) to total lower 
polyoxyalkylene(s) may typically range from about 1:1 to about 1:2, and in some specific 
embodiments is about 1:1.67.  
[00291 The solvent system will generally compose about 30% to about 60% by weight of the high 
dosage mucoadhesive MTZ aqueous-based gel. The exact amount used will depend, at least in part, 
on the desired amount of MTZ to be included in the gel. In some specific embodiments, the solvent 
system represents about 40-45% by weight of the high dosage mucoadhesive MTZ aqueous-based 
gel.  
[0030] The quantities of the components of the solvent system can also be described relative to the 
high dosage mucoadhesive MTZ aqueous-based gels. In some specific embodiments, the high dosage 
mucoadhesive MTZ aqueous-based gels comprise from about 1.5% to about 2% by weight total lower 
aromatic alcohol(s) (for example, benzyl alcohol), about 15% to about 25% by weight total lower 
aliphatic diol(s) (for example, propane-1,2-diol) and/or about 15% to about 25% by weight total 
lower polyoxyalkylene(s) (for example, PEG 400). In some specific embodiments, the high dosage 
mucoadhesive MTZ aqueous-based gels comprise about 1.5% to about 2% by weight total lower 
aromatic alcohol(s) (for example, benzyl alcohol), about 15% by weight total lower aliphatic diol(s) 
(for example, propane-1,2-diol) and/or about 25% by weight total lower polyoxyalkylene(s) (for 
example, PEG 400). Other specific embodiments are described in the Detailed Description section, as

are additional solvents and agents useful to solubilize MTZ in connection with the high dosage 
mucoadhesive MTZ aqueous-based gels described herein.  
[0031] The pH of the high dosage mucoadhesive MTZ aqueous-based gels described herein should 
generally match the pH of the intended area of application, for example, when intended for 
intravaginal application, the pH of a healthy vagina. While not intending to be bound by any 
particular theory, it is believed that matching the pH of the healthy vagina permits beneficial 
Lactobacillus to flourish. Accordingly, for gels intended for intravaginal application, the pH should 
generally be in the range of about pH 3 to about pH 5, for example a pH of about pH 4. The pH can 
be adjusted and/or maintained with the aid of acids, bases and buffers, as is well-known in the art.  
For example, the pH of the gel may be adjusted and/or maintained by utilizing as the aqueous phase 
of the gel a buffer having a suitable normality and pH. Alternatively, the pH of the aqueous phase 
may be adjusted with an acid or base prior to adding the gelling agent. After gelling, the pH may be 
adjusted further with an acid or base. This latter method may be advantageous for preparing gels 
utilizing gelling agents that gel most efficiently outside the desired pH range of the resultant gel. For 
example, carbomers gel most efficiently around neutral pH. High dosage mucoadhesive MTZ 
aqueous-based gels suitable for intravaginal application may be obtained by adjusting the pH of the 
gelling solution to approximately neutral for gelling and then adjusting the pH of the resultant gel to 
within a range of about pH 3 to about pH 5 with an acid. However, it has been discovered that high 
dosage mucoadhesive MTZ aqueous-based gels utilizing certain pH-sensitive mucoadhesive gelling 
polymers, such as, for example, carbomer and polycarbophil polymers, having a pH in the desired 
range for intravaginal application can be obtained without the aid of a buffer or pH adjustment.  
[0032] The high dosage mucoadhesive MTZ aqueous-based gels described herein can also include 
other additional components, such as, for example, one or more preservatives, as is well-known in the 
art. When used, preservative(s) should generally comprise no more than about 1% or 2% by weight 
of the high dosage mucoadhesive MTZ aqueous-based gel. The choice of preservative(s) is not 
critical. Suitable useful preservatives are described in more detail in the Detailed Description section.  
In some specific embodiments the one or more preservative(s) are esters of 4-hydroxy benzoic acid, 
also known as parabens. Suitable parabens include lower alkyl esters of 4-hydroxy benzoic acid, such 
as, for example, methyl 4-hydroxybenzoate (methyl parben), ethyl 4-hydroxybenzoate (ethyl paraben) 
and propyl 4-hydroxy-benzoate (propyl paraben).

[00331 Skilled artisans will appreciate that solvents used to solubilize the MTZ in the high dosage 
mucoadhesive MTZ aqueous-based gels described herein may also have preservative properties. As a 
specific example, benzyl alcohol has well known preservative properties. When used as a solvent in 
the novel solvent system, the preservative properties can be used to advantage. Indeed, gels including 
solvents with preservative properties need not necessarily include additional preservatives. Gels that 
utilize the preservative properties of system solvents should, in cases where the solvent may degrade 
or oxidize over time, include an amount of overage that takes into account the degradation and/or 
oxidation such that the gel retains an amount of undegraded or unoxidized solvent having effective 
preservative properties after a desired period of time. For example, benzyl alcohol is known to 
oxidize to benzaldehyde, which does not have preservative properties. In embodiments of the high 
dosage mucoadhesive MTZ aqueous-based gels described herein that employ benzyl alcohol as both 
an MTZ solvent and as a preservative, an amount of benzyl alcohol should be included in the gel that, 
in addition to solubilizing the MTZ, yields a preservative effect for the duration of the expected shelf 
life of the gel. Overage amounts of benzyl alcohol or other solvents employed in the solvent system 
that are being used in part as preservatives can be determined based upon the degradation and/or 
oxidation properties and kinetics of the particular solvent under the desired conditions of storage.  
[0034] Embodiments of high dosage mucoadhesive MTZ aqueous-based gels that include solvents 
having preservative properties may also include one or more additional preservatives, and/or 
preservatives designed to protect the solvent from degradation and/or oxidation. For example, in the 
case of benzyl alcohol, the high dosage gels described herein may include one or more additional 
preservatives that have antioxidant properties, in part to protect the benzyl alcohol from oxidation. In 
a specific embodiment, high dosage mucoadhesive MTZ aqueous-based gels comprising benzyl 
alcohol or other solvents that oxidize include one or more parabens as additional preservatives. In 
some specific embodiments the high dosage mucoadhesive MTZ aqueous-based gels comprise about 
0.1% by weight total parabens, and in some specific embodiments about 0.02% by weight methyl 
paraben and about 0.08% by weight propyl paraben.  
[0035] The high dosage mucoadhesive MTZ aqueous-based gels also include water, either in the 
form of pure water, or in the form of an aqueous buffer. Typically, the amount of water included in 
the gel will be less than about 70% by weight, more typically less than about 60% by weight, and in 
some specific embodiments in the range of about 45% to about 55% by weight.

[0036] As noted above, several embodiments of high dosage mucoadhesive MTZ aqueous-based 
gels prepared with the novel solvent system described herein deliver unexpectedly high local 
concentrations of MTZ, and significantly higher local concentrations of MTZ than a conventional 
0.75 wt% MTZ gel, in in vitro skin permeation experiments carried out in a Franz Cell with human 
cadaver skin (and also silicone membranes). Indeed, as is described in more detail in the Examples 
section, virtually every high dosage MTZ aqueous-based gel tested locally delivered in the range of 
about 25- to about 55-fold more MTZ, when normalized for concentration, to the stratum corneum 
than a conventional 0.75 wt% MTZ gel. Despite the higher local MTZ concentrations delivered by 
the high dosage mucoadhesive MTZ aqueous-based gels described herein, significantly less MTZ was 
observed in receiver fluid as compared to a conventional 0.75 wt% MTZ gel in in vitro skin 
permeation experiments carried out in a Franz Cell with human cadaver skin. As is described in more 
detail in the Detailed Description section, virtually every high dosage MTZ gel tested yielded in the 
range of about 1- to about 20-fold less MTZ in receiver fluid, when normalized for concentration, 
than a conventional 0.75 wt% MTZ gel in this experiment.  
[0037] Although not intending to be bound by any theory, it is believed that these properties may be 
significant and/or important to therapeutic applications, as they permit high local concentrations of 
MTZ to be delivered, potentially increasing efficacy, while at the same time in certain topical 
applications reducing systemic exposure, thereby reducing untoward side effects. Accordingly, in 
some embodiments, the various components of the high dosage mucoadhesive MTZ aqueous-based 
gels are selected so as to yield a high dosage gel in which the surface levels of MTZ measured in an 
in vitro Franz cell skin permeation study carried out with human cadaver skin or a silicone membrane, 
when normalized for concentration, are at least about 25-fold higher, and in some specific 
embodiments about 55-fold higher, than the level measured with a conventional 0.75 wt% MTZ gel, 
such as METROGEL VAGINAL@. In some embodiments, the various components of the high 
dosage mucoadhesive MTZ aqueous-based gels are selected so as to yield a high dosage gel in which 
the levels of MTZ measured receiver fluid in an in vitro Franz cell skin permeation study carried out 
with human cadaver skin, when normalized for concentration, are at least about 1-fold lower, and in 
some specific embodiments about 20-fold lower, than the level measured with a conventional 0.75 
wt% MTZ gel, such as METROGEL VAGINAL®. A specific in vitro Franz cell experiment that can 
be used for the comparative studies described in Example 6.

[00381 The high dosage mucoadhesive MTZ aqueous-based gels described herein can be used for 
any purpose where topical treatment with MTZ is desirable. Due to their degree of mucoadhesion, 
they are especially useful for treating women suffering from and/or diagnosed with BV.  
[0039] Accordingly, in another aspect, the present disclosure provides methods of treating women 
suffering from and/or diagnosed with BV using the high dosage mucoadhesive MTZ aqueous-based 
gels described herein. The methods generally involve applying intravaginally to a woman suffering 
from and/or diagnosed with BV an amount of a high dosage mucoadhesive MTZ aqueous-based gel 
as described herein sufficient to provide therapeutic benefit. The clinical criteria for diagnosis, as 
well as criteria for establishing therapeutic benefit, are described in more detail in the Detailed 
Description section. In some specific embodiments, the amount of high dosage mucoadhesive MTZ 
aqueous-based gel applied in a single application contains from about 60 mg to about 100 mg MTZ.  
In other specific embodiments, the amount of high dosage mucoadhesive MTZ aqueous-based gel 
applied in a single application contains from about 60 mg to about 90 mg MTZ, in still other specific 
embodiments from about 60 mg to about 80 mg MTZ, and in still other specific embodiments from 
about 60 mg to about 70 mg MTZ. In still other specific embodiments, the amount of high dosage 
mucoadhesive MTZ aqueous-based gel applied in a single application contains about 65 mg MTZ.  
[0040] The frequency and duration of application can vary, and may depend upon the desired 
outcome. Generally, the gel is applied once per day for a period of one, two, three, four or five days.  
It has been found that significant therapeutic benefit is achieved with a single application of high 
dosage mucoadhesive MTZ aqueous-based gel containing about 65 mg MTZ. Accordingly, in some 
embodiments the high dosage mucoadhesive MTZ aqueous-based gel is applied as a single 
application. It has also been found that application of a high dosage mucoadhesive MTZ aqueous
based gel containing about 65 mg MTZ once per day for a period of five days yielded less incidence 
of BV recurrence than a similar course of treatment with an FDA-approved 0.75 wt% MTZ gel, and 
virtually no incidence of vulvovaginal candidiasis post-therapy. Accordingly, in some embodiments 
the high dosage mucoadhesive MTZ aqueous-based gel is applied once per day for a period of five 
days.  
[0041] For use, the high dosage mucoadhesive MTZ aqueous-based gels can be packaged in any 
form that is convenient for the desired mode of application. In specific embodiments useful for

intravaginal application, the high dosage mucoadhesive MTZ aqueous-based gel may be packaged in 
unit dosage form, as a specific example as a pre-filled, single dose syringe-type applicator.  
[00421 When used to treat women suffering from and/or diagnosed with BV, the high dosage 
mucoadhesive MTZ aqueous-based gels described herein provide numerous surprising advantages, 
including, for example: (1) effective treatment of BV following a single application, unlike existing 
therapies with 0.75 wt% MTZ gels, for example, METROGEL VAGINAL@, which requires 
administration once or twice daily for 5 days to achieve a therapeutic effect; (2) increased efficacy as 
compared to METROGEL VAGINAL@ following application once per day for 5 days, as determined 
by any one of increased cure rates, decreased time to resolution of symptoms, increased time to 
recurrence of symptoms, and/or lower incidence of vulvovaginal candidiasis.  
[00431 It should be understood that the above summary is not intended to describe every 
embodiment or every implementation of the various inventions disclosed herein. The Detailed 
Description and Examples section further exemplify illustrative embodiments. The various 
embodiments described herein are intended to be disclosed in combinations, as if each specific 
combination were explicitly disclosed. The Examples are representative only and should not be 
interpreted as exclusive, or limiting the scope of the various inventions disclosed herein.  
5. BRIEF DESCRIPTION OF THE FIGURES 
[00441 FIG. 1 provides a graph illustrating the mucoadhesive properties of exemplary high dosage 
mucoadhesive MTZ aqueous-based gels MG32PB and MG33PB to porcine gastric mucosa. Data 
show the percentage of MTZ that remains in the gastric mucosa as a function of time. For this 
experiment, data were taken every 15 sec for the first 5 min.  
[00451 FIG. 2 provides a graph illustrating the mucoadhesive properties of exemplary high dosage 
mucoadhesive MTZ aqueous-based gels MG32PB and MG33PB to porcine gastric mucosa. Data 
show the percentage of MTZ that remains in the gastric mucosa as a function of time. For this 
experiment, data were taken every min for the first 15 min.  
[0046] FIGS. 3A-3B provide graphs illustrating the mean amount (pig; ±SEM) of 14C-labeled MTZ 
recovered from various skin layers from various exemplary high dosage mucoadhesive MTZ 
aqueous-based gels in an in vitro Franz cell skin permeation experiment carried out with human 
cadaver skin.

[0047] FIGS. 4A-4B provide graphs illustrating the recovery data of FIGS. 3A and 3B, respectively, 
represented as a mean percentage (+SEM) of the total 4C-labeled MTZ applied.  
[0048] FIGS. 5A-5B provide graphs illustrating different views of the recovery data of FIG. 3A and 
FIG. 3B, respectively.  
[00491 FIGS. 6A-6B provide graphs illustrating different views of the recovery data of FIG. 4A and 
FIG. 4B, respectively.  
[0050] FIG. 7 provides a graph illustrating the mean amount (Rg) of MTZ recovered from the 
surface and within vaginal tissue from an exemplary high dosage MTZ mucoadhesive aqueous-based 
gel and a control gel 24 hours after application in an in vitro Franz cell experiment carried out with 
porcine vaginal tissue. Data are mean ±SEM (n = 5).  
[0051] FIG. 8 provides a graph illustrating the mean amount of MTZ that permeated through porcine 
vaginal tissue (Rg/cm 2 vaginal tissue) in the Franz cell experiment of FIG. 7. Data are 
mean ±SEM (n = 5).  
[00521 FIG. 9 provides a graph comparing the ATP released from epidermal membrane samples 
infected with G. vaginalis following a 24 hr treatment with different exemplary high dosage 
mucoadhesive MTZ aqueous-based gels (n = 3 for active gels; n = 2 for placebo gels and control).  
[00531 FIG. 10 provides a graph comparing the ATP released from epidermal membrane samples 
infected with G. vaginalis following treatment with exemplary high dosage MTZ gel MG33PB at 
different dosing times of 4, 8 and 24 hr (n = 3 for MG33PB; n = 2 for placebo gels and control).  
[00541 FIG. 11 provides a graph comparing the ATP released from epidermal membrane samples 
infected with G. vaginalis following a 2 hr treatment with different high dosage mucoadhesive MTZ 
aqueous-based gels (n = 6 for active gels and control; n = 3 for placebo gels).  
[00551 FIG. 12 provides a graph showing the zones of inhibition on the growth of G. vaginalis of 
exemplary high dosage mucoadhesive MTZ aqueous-based gel MG33PB and various placebo 
versions containing different quantities of benzyl alcohol.

6. DETAILED DESCRIPTION 
[0056] A more complete appreciation of the various inventions disclosed herein, and many of the 
attendant advantages thereof, is provided by the detailed description that follows.  
6.1. Definitions 
[00571 As used herein throughout the specification and in the appended claims, the following terms 
and expressions are intended to have the following meanings: 
[0058] The indefinite articles "a" and "an" and the definite article "the" are intended to include both 
the singular and the plural, unless the context in which they are used clearly indicates otherwise.  
[0059] "At least one" and "one or more" are used interchangeably to mean that the article may 
include one or more than one of the listed elements.  
[00601 Unless otherwise indicated, it is to be understood that all numbers expressing quantities, 
ratios, and numerical properties of ingredients, reaction conditions, and so forth, used in the 
specification and claims are contemplated to be able to be modified in all instances by the term 
"about".  
6.2. Detailed Description of Specific Exemplary Embodiments 
[00611 As noted in the Summary, the present disclosure provides, among other things, high dosage 
mucoadhesive metronidazole ("MTZ") aqueous-based gels that are useful for topical delivery of MTZ 
to treat, among other things, various microorganism infections, and in a specific embodiment for 
intravaginal application as a therapeutic approach towards the treatment of women suffering from, or 
diagnosed with, bacterial vaginosis ("BV"). The high dosage mucoadhesive MTZ aqueous-based 
gels generally comprise MTZ and one or more gelling polymers, in specific embodiments one or 
more mucoadhesive gelling polymers.  
[00621 MTZ, also known as 2-(2-methyl-5-nitro-lH-imidazol-1-yl)ethanol, is a well-known 
antimicrobial agent, having activity against anaerobic Gram-negative bacilli including Fusobacterium 
species and Bacteroides species (e.g., B. fragilis, B. distasonis, B. ovatus, B. thetaioaomicron, and B.  
vulgates); anaerobic Gram-positive bacilli including Clostridium species and susceptible strains of 
Eubacterium; and anaerobic Gram-positive cocci including Peptostreptococcus species.

[00631 MTZ can be included in the high dosage gels described herein in the form of a free base or as 
a salt formed with pharmaceutically acceptable acids. Inorganic acids suitable for forming 
pharmaceutically acceptable salts include, by way of example and not limitation, hydrohalide acids 
(e.g., hydrochloric acid, hydrobromic acid, hydriodic, etc.), sulfuric acid, nitric acid, phosphoric acid 
and the like. Organic acids suitable for forming pharmaceutically acceptable salts include, by way of 
example and not limitation, acetic acid, trifluoroacetic acid, propionic acid, hexanoic acid, 
cyclopentanepropionic acid, glycolic acid, oxalic acid, pyruvic acid, lactic acid, malonic acid, 
succinic acid, malic acid, maleic acid, fumaric acid, tartaric acid, citric acid, palmitic acid, benzoic 
acid, 3-(4-hydroxybenzoyl) benzic acid, cinnamic acid, mandelic acid, alkylsulfonic acids (e.g., 
methanesulfonic acid, ethanesulfonic acid, 1,2-ethane-disulfonic acid, 2-hydroxyethanesulfonic acid, 
etc.), arylsulfonic acids (e.g., benzenesulfonic acid, 4-chlorobenzenesulfonic acid, 2
naphthalenesulfonic acid, 4-tuluenesulfonic acid, camphorsulfonic acid, etc.), 4-methylbicyclo[2.2.2]
oct-2-ene-1-carboxylic acid, glucoheptonic acid, 3-phenylpropionic acid, trimethylacetic acid, tertiary 
butylacetic acid, lauryl sulfuric acid, gluconic acid, glutamic acid, hydroxynaphthoic acid, salicylic 
acid, stearic acid, muconic acid, and the like.  
[00641 MTZ is available commercially or can be synthesized by well-known methods.  
[00651 The high dosage mucoadhesive MTZ aqueous-based gels described herein generally 
comprise MTZ in amounts ranging from about 1% by weight to about 2% by weight. In specific 
embodiments, the gels described herein comprise about 1.0%, about 1.1%, about 1.2%, about 1.3%, 
about 1.4%, about 1.5%, about 1.6%, about 1.7%, about 1.8%, about 1.9% or about 2.0% by weight 
MTZ.  
[0066] The high dosage mucoadhesive MTZ aqueous-based gels also comprise one or more gelling 
polymers, and in specific embodiments one or more mucoadhesive gelling polymers that impart the 
gels with their mucoadhesive and gel-like properties. A variety of polymers that form mucoadhesive 
gels in aqueous-based solutions that are suitable for use in the mucoadhesive aqueous-based gels 
described herein are known in the art, and include by way of example and not limitation, 
polysaccharide hydrocolloids (including, for example, mucilages, gums such as xanthan gum and 
tragacanth, and glucans), celluloses and modified celluloses (including, for example, alkyl celluloses, 
hydroxyalkyl celluloses, carboxy celluloses and sodium carboxy celluloses), poloxomers (copolymers 
of polyoxyethylene and polyoxypropylene, also known as PLURONICS@), carbomers (crosslinked

polymers of acrylic acid), polycarbophils (polymers of polyacrylic acid crosslinked with divinyl 
glycol), veegum (magnesium aluminum silicate), polyvinyl alcohol (PVA), gelatin, sodium alginate 
and polyvinylpyrrolidone (PVP). Exemplary suitable mucilages can be found, for example, in 
Malviya et al., 2011, "Applications of Mucilages in Drug Delivery - A Review," Advan Biol Res 
5(1):1-7, and the references cited therein, the disclosures of which are incorporated herein by 
reference.  
[0067] In some specific embodiments, the gelling polymer(s) are cross-linked polymers of acrylic 
acids, such as for example carbomers or polycarbophils, and/or cellulosic polymers. Suitable 
cellulosic polymers include, but are not limited to, carboxy methyl cellulose (CMC), methylcellulose, 
ethyl cellulose, hydroxyl ethyl cellulose (NEC or HHX), hydroxyl propyl cellulose (HPC) and 
hydroxyl propyl methyl cellulose (HPMC). Suitable carbomers include, but are not limited to the 
various polymers sold under the trade name CARBOPOL@ by Lubrizol Advanced Materials, 
Cleveland, Ohio, including, for example, CARBOPOL@ homopolymers (polymers of acrylic acid 
crosslinked with allyl sucrose or allyl pentaerythritol) such as CARBOPOL@ 71 G NF, 
CARBOPOL@ 971P NF, CARBOPOL@ 974P NF, CARBOPOL@ 980 NF, and CARBOPOL@ 981 
NF; CARBOPOL@ copolymers (polymers of acrylic acid and C O-C3 0 alkyl acrylate crosslinked 
with allyl pentaerythritol) such as PEMULENTM TR-1 NF and PEMULENTM TR-2 NF; 
CARBOPOL@ interpolymers (carbomer homopolymers or copolymers that contain a block 
copolymer of polyethylene glycol and long chain alkyl acid ester) such as CARBOPOL@ ETD 2020 
NF and CARBOPOL@ Ultrez 10 NF; "traditional" carbomers such as carbomer 934 (CARBOPOL@ 
934 NF), carbomer 934P (CARBOPOL@ 934P NF), carbomer 940 (CARBOPOL@ 940 NF), 
carbomer 941 (CARBOPOL@ 941 NF) and carbomer 1342 (CARBOPOL@ 1342P NF); and 
polycarbophil (NOVEON@ AA-1 USP).  
[00681 Any of these and/or other mucoadhesive gelling polymers can be used, singly or in 
combinations, in the high dosage mucoadhesive MTZ aqueous-based gels described herein.  
[0069] The one or more mucoadhesive gelling polymers are typically used in quantities such that the 
resultant high dosage mucoadhesive MTZ aqueous-based gel has a viscosity in the range of about 
200,000 - 400,000 mPa at 25 'C, and in some specific embodiments in the range of about 250,000 
350,000 mPa at 25 'C, measured using the controlled shear rate ramp method, a Bohlin CVO 
100 rheometer and the rheometer settings noted in Table 11 (Example 5, infra). Depending upon the

specific gelling polymer(s) and gelling conditions used, aqueous-based gels having viscosities in this 
range are generally achieved by including in the gels a total quantity of gelling polymer(s) ranging 
from about 0.5% to about 5% by weight. In some specific embodiments, the high dosage 
mucoadhesive MTZ aqueous-based gels described herein will include about 1% to about 3% by 
weight total gelling polymer(s), and in some specific embodiments about 2% by weight total gelling 
polymer(s).  
[0070] Gels designed for intravaginal application should ideally exhibit a degree of mucoadhesion to 
prevent the gel from leaking when applied. Gels utilizing cellulosic and/or acrylic acid mucoadhesive 
gelling polymers that have viscosities in the ranges discussed above should have a suitable degree of 
mucoadhesion. Different gelling polymers exhibit different degrees of mucoadhesion. Gelling 
polymers yielding a high dosage mucoadhesive MTZ aqueous-based gel that have a degree of 
mucoadhesion that is within about ±10% that of exemplary gel MG33PB (described in Example 2 and 
Table 5) can suitably be used. In a specific exemplary embodiment, the mucoadhesive polymer(s) are 
selected from the group consisting of a hydroxyalkyl cellulose, a carbomer, a polycarbophil and 
mixtures thereof. In another specific exemplary embodiment, the mucoadhesive polymer(s) is a 
polycarbophil, such as, for example, the polycarbophil sold under the trade name NOVEON@ AA- 1 
Polycarbophil by Lubrizol, Inc.  
[00711 High dosage mucoadhesive MTZ aqueous-based gels having suitable viscosities, 
mucoadhesion and other desirable properties utilizing carbomer 934, hydroxyethyl cellulose or 
polycarbophil as the mucoadhesive gelling polymer are provided in Example 2.  
[00721 As noted in the Summary, the solubility of MTZ presents problems when attempting to 
formulate MTZ in aqueous-based formulations, such as aqueous-based gels. Specific embodiments 
of the high dosage mucoadhesive MTZ aqueous-based gels described herein utilize a novel solvent 
system which has been discovered to yield homogenous gels containing MTZ at concentrations as 
high as 2% or more by weight that are stable for long periods of time, for example at least about 6 
months, when stored at temperatures ranging from about 25 'C to about 40 'C. Surprisingly, such 
high dosage mucoadhesive MTZ aqueous-based gels can be prepared without the aid of agents 
commonly used to enhance the solubility of MTZ in aqueous solutions, such as cyclodextrins, beta 
cyclodextrins, niacin, niacinamide and/or surfactants.

[0073] As used herein, "stable" means that the gel exhibits the following properties: (1) an MTZ 
purity of at least about 95% when stored at a temperature of about 25 'C for a period of at least 6 
weeks; (2) no appreciable increase (e.g., no more than about a 2-fold to 3-fold increase) in formation 
of crystals and/or particulates upon microscopic visual inspection at a magnification of 40x when 
stored at a temperature of about 25 'C for a period of at least 6 weeks, as compared to a baseline 
value and (3) a change in viscosity of no more than about ±50% as measured at 25 *C when stored at 
a temperature of about 25 'C for a period of about 6 weeks, as compared to a baseline value or a 
control sample stored at a temperature in the range of about 2-8 'C. In addition, it is desirable, but 
not required, that stable gels exhibit the following additional properties: (4) a change of pH less than 
about ±0.3 pH units when stored at a temperature of about 25 'C for a period of 6 weeks, as compared 
to a baseline value or a control sample stored at a temperature in the range of about 2-8 'C; (5) a 
change in the efficacy of the preservative of no more than about +20% when stored at about 25 'C for 
a period of at least about 6 weeks, as compared to a baseline value or a control sample stored at a 
temperature in the range of about 2-8 'C. Assays suitable for measuring the stability of high dosage 
mucoadhesive MTZ aqueous-based gels are provided in Examples 4 and 5. Typically, the specific 
components and quantities of the novel solvent system are selected so as to yield a high dosage 
mucoadhesive MTZ aqueous-based gel that is stable as defined herein. Guidance for selecting 
solvent systems useful for preparing stable high dosage MTZ aqueous-based gels having specific 
quantities of MTZ is provided by way of the various exemplary high dosage gels disclosed in the 
Examples section.  
[0074] In some specific embodiments, the components and quantities of the novel solvent system are 
selected to yield a stable high dosage mucoadhesive MTZ aqueous-based gel having the MTZ purity, 
homogeneity and viscosity properties discussed above, and optionally the pH and preservative 
efficacy properties discussed above, when stored at a temperature of about 40 'C for a period of about 
6 weeks. In other specific embodiments, the components and quantities of the novel solvent system 
are selected to yield a stable high dosage mucoadhesive MTZ aqueous-based gel having the above
discussed MTZ purity, homogeneity and viscosity properties, and optionally the above-discussed pH 
and preservative efficacy properties, when stored at a temperature of in the range of about 25-40 'C, 
and in specific embodiments at a temperature of about 25 'C or about 40 'C, for a period of 6 months, 
or even more, for example, for periods as long as 18 months. In yet other specific embodiments, the 
components and quantities of the novel solvent system are selected to yield a stable high dosage

mucoadhesive MTZ aqueous-based gel having the above-described MTZ purity, homogeneity, 
viscosity, pH and optionally preservative efficacy properties discussed above when stored at a 
temperature in the range of about 25-40 'C, and in specific embodiments at a temperature of about 
'C or about 40 'C, for a period of about 6 months, or even more, for example, for periods as long 
as about 18 months.  
[00751 Various novel solvent systems are described in the Summary section, supra. In some specific 
embodiments, the novel solvent system is a ternary system that comprises one or more lower aromatic 
alcohol, one or more lower aliphatic diol and/or one or more polyoxyalkylene having a MW in the 
range of about 200 to about 600 ("lower polyoxyalkylene").  
[00761 As used herein, "lower alcohol" includes saturated and unsaturated non-aromatic and 
aromatic alcohols having from 1 to 15 carbon atoms and that may optionally include one or more 
heteroatoms, for example, one or more oxygen atoms, replacing the carbon atom(s). Lower non
aromatic alcohols may include straight-chained, branched or cyclic primary, secondary or tertiary 
lower aliphatic alcohols and lower heteroapliphatic alcohols. Examples of lower aliphatic alcohols 
include, but are not limited to, methanol, ethanol, propan- 1 -ol, propan-2-ol, butan- 1 -ol, butan-2-ol, 2
methylpropan-1-ol, 2-methylpropan-2-ol, pentan-1-ol, pental-2-ol, pentan-3-ol, 3-methylbutan-1-ol, 
hexan-1-ol, hexan-2-ol, hexan-3-ol, and cyclohexanol. Examples of lower heteroaliphatic alcohols 
include, but are not limited to, alkylene glycol monoalkyl ethers such as, for example, ethylene glycol 
monoalkyl ethers, propylene glycol monoalkyl ethers and tetraglycol. In some specific embodiments, 
lower non-aromatic alcohols such as lower aliphatic and lower heteroaliphatic alcohols contain from 
one to 8 non-hydrogen atoms, including any heteroatoms.  
[00771 Lower aromatic alcohols include lower alcohols that have aromatic character, which may be 
contributed by an aromatic (e.g., phenyl, naphthyl, etc.) pendant group on a non-aromatic alcohol, 
such as an aliphatic alcohol or a heteroaliphatic alcohol. Accordingly, the alcohol group may be 
phenolic, primary, secondary or tertiary. Examples of lower aromatic alcohols include, but are not 
limited to, phenol, benzyl alcohol, 2-methylbenzyl alcohol, and phenoxyethanol.  
[00781 As used herein, "lower aliphatic diol" includes saturated or unsaturated, straight-chained, 
branched or cyclic aliphatic diols containing from two to ten carbon atoms. The alcohol groups may 
be, independently of each other, primary, secondary or tertiary. In some specific embodiments, the 
lower aliphatic diol is a saturated or unsaturated straight-chain or branched diol, referred to herein as

a "lower alkylene diol" (also referred to as "lower glycols"). In some specific embodiments, the 
lower alkylene diol is a saturated straight-chained or branched diol, referred to herein as a "lower 
alkyl diol." In some specific embodiments, the lower alkyl diol is a straight-chain diol, referred to 
herein as a "lower n-alkyl diol." Specific examples of lower aliphatic diols useful in the solvent 
systems and gels described herein include, but are not limited to, ethane-1,2-diol (ethylene glycol), 
propane-1,2-diol (propylene glycol), propane-1,3-diol, butane-1,2-diol, butane-1,3-diol, 
butane-2,3-diol, butane-1,4-diol, pentane-1,5-diol, pentane-1,2-diol, 2-methyl-2,4-pentanediol, etc.  
[00791 As used herein, "lower polyoxyalkylene" includes polymers formed from lower aliphatic 
diols and that have a molecular weight in the range of about 200 to about 600. Specific examples of 
lower polyoxyalkylenes useful in the solvent systems and gels described herein include, but are not 
limited to, polyethylene glycol (for example, PEG 200, PEG 400 and PEG 600), polypropylene glycol 
(for example PPG-9) and dipropylene glycol.  
[0080] The novel ternary solvent system generally comprises about 3.5% to about 5% by weight 
total lower aromatic alcohol(s), and about 95% to about 96.5% by weight of a mixture of total lower 
aliphatic diols and polyoxyalkylenes, where the weight ratio of the total lower aliphatic diols to total 
polyoxyalkylenes is in the range of about 1:1 to about 1:2, and in some specific embodiments about 
1:1.67.  
[0081] The solvent system may include additional agents and solvents, such as, for example, 
additional agents or solvents that enhance the solubility of MTZ in aqueous solutions, such as, for 
example, cyclodextrins, beta-cyclodextrins, niacin and/or niacinamide. However, it has been 
discovered that high dosage MTZ aqueous-based gels that are homogeneous and have good shelf 
stability properties can be prepared using solvent systems that do not include such additional 
solubilizing agents, and in specific embodiments include only lower aromatic alcohols, lower
aliphatic diols and lower polyoxyalkylenes. Accordingly, in some specific embodiments, the solvent 
system and resultant gels are substantially free of agents that enhance the solubility of MTZ in 
aqueous solutions, such as cyclodextrins, beta-cyclodextrins, niacin and/or niacinamide. In other 
specific embodiments, the solvent system is a ternary system that consists only of one or more lower 
aromatic alcohol(s), one or more lower aliphatic diol(s) and one or more lower polyoxyalkylene(s).  
[0082] The solvent system will generally represent about 30% to about 60% by weight of the high 
dosage mucoadhesive MTZ aqueous-based gel, in certain embodiments about 40% to about 50% by

weight of the gel, and in some specific embodiments about 40% to about 45% by weight of the gel, 
although the gel may include higher or lower amounts of total solvents.  
[00831 A particularly useful ternary solvent system comprises benzyl alcohol as the one or more 
lower aromatic alcohol, propane-1,2-diol (propylene glycol) as the one or more lower aliphatic diol 
and polyethylene glycol having a MW of 400 (PEG 400) as the one or more lower polyoxyalkylene.  
[0084] In some specific embodiments, solvent systems useful for solubilizing MTZ in the high 
dosage mucoadhesive aqueous-based gels described herein comprise, relative to the resultant high 
dosage mucoadhesive MTZ aqueous-based gel: (a) a polyoxyalkylene such as polyethylene glycol, 
e.g., PEG 400, at a concentration of from about 10% to about 50% by weight, and for example from 
about 20% to about 40% by weight, or from about 20% to about 30% by weight, and in a specific 
embodiment, about 25% by weight; (b) a lower aromatic alcohol such as phenoxyethanol or benzyl 
alcohol, and in a specific embodiment benzyl alcohol, from about 1.3% to about 2.5% by weight, or 
from about 1.5%-2.0% by weight, and in a specific embodiment about 2.0% by weight; and/or (c) a 
lower aliphatic diol, such as propane-1,2-diol, at a concentration of greater than about 3% to about 
20% by weight, for example from about 15%-20% by weight, and in a specific embodiment about 
15% by weight.  
[0085] In still other specific embodiments, the solvent systems comprise: (a) PEG 400; (b) PEG 400 
and a lower aromatic alcohol, such as benzyl alcohol; (c) PEG 400, a lower aromatic alcohol, such as 
benzyl alcohol and propane-1,2-diol; (d) a lower aromatic alcohol, such as benzyl alcohol; and/or (e) 
propane-1,2-diol.  
[0086] In still other specific embodiments, the solvent systems comprise, relative to the resultant 
high dosage MTZ mucoadhesive aqueous-based gel: (a) about 25% PEG 400 by weight; (b) about 
25% PEG 400 by weight and about 2% benzyl alcohol by weight; or (c) about 25% PEG 400 by 
weight, about 2% benzyl alcohol by weight and about 15% propane-1,2-diol by weight.  
[00871 For gels designed for intravaginal application, it is preferable to use concentrations of benzyl 
alcohol that do not cause irritation at the target site in the vaginal area. Accordingly, in some specific 
embodiments in which the solvent system includes benzyl alcohol, the amount of benzyl alcohol 
included in the gel ranges from about 1.3% to about 2.5% by weight, for example about 1.5% to 
about 2% by weight, and in a specific embodiment about 2% by weight.

[0088] In still other specific embodiments, the high dosage mucoadhesive MTZ aqueous-based gels 
described herein comprise propane-1,2-diol at a concentration of at least about 3% and up to about 
20% by weight, for example from about 15% to about 20% by weight, and in a specific embodiment 
about 15% by weight. In yet other specific embodiments, the gels comprise about 1.3% MTZ by 
weight and about 25% PEG 400 by weight. In yet other specific embodiments they comprise about 
1.3% MTZ by weight, about 25% PEG 400 by weight, and about 2% benzyl alcohol by weight. In 
yet other specific embodiments they comprise about 1.3% MTZ by weight, about 25% PEG 400 by 
weight, about 2% benzyl alcohol by weight, and about 15% propylene glycol by weight.  
[00891 In still other specific embodiments, solvent systems useful to make the high dosage 
mucoadhesive MTZ aqueous-based gels described herein comprise, relative to the gel, any one of (a) 
PEG 400 at a concentration of from about 10% to about 50% by weight, for example between about 
20% and about 40% by weight or between about 20% and about 30% by weight, and in a specific 
embodiment about 25% by weight; (b) benzyl alcohol from about 1.3% to about 2.5% by weight, for 
example from about 1.5% to about 2% by weight, and in a specific embodiment about 2% by weight; 
(c) propane-1,2-diol at a concentration of at least about 3% and up to about 20% by weight, for 
example from about 15% to about 20% by weight, and in a specific embodiment about 15% by 
weight; (d) about 25% PEG 400 by weight; (e) about 25% PEG 400 by weight and about 2% benzyl 
alcohol by weight; and (f) about 25% PEG 400 by weight, about 2% benzyl alcohol by weight and 
about 15% propylene glycol by weight.  
[0090] The pH of the high dosage mucoadhesive MTZ aqueous-based gels described herein should 
generally match the pH of the intended area of application, for example, when intended for 
intravaginal application, the pH of a healthy vagina. Accordingly, for gels intended for intravaginal 
application, the pH should generally be in the range of about pH 3 to about pH 5, for example a pH of 
about pH 4. The pH may be adjusted and/or maintained with the aid of acids, bases buffers and other 
pH-adjusting agents, as is well-known in the art and discussed in the Summary section.  
[0091] The high dosage mucoadhesive MTZ aqueous-based gels described herein can also include 
other additional components, such as, for example, one or more preservatives, as is well-known in the 
art. When used, preservative(s) should generally comprise no more than about 1% or 2% by weight 
of the high dosage mucoadhesive MTZ aqueous-based gel, and will typically comprise about 0.25% 
to about 1.0% by weight of the high dosage mucoadhesive MTZ aqueous-based gel. The choice of

preservative(s) is not critical. Numerous preservatives suitable for use in pharmaceutical 
formulations are well-known to those of skill. Any of these preservatives, and in some specific 
embodiments those having antimicrobial properties, can be used singly or in combinations in the high 
dosage mucoadhesive MTZ aqueous-based gels described herein. In some specific embodiments the 
one or more preservative(s) are esters of 4-hydroxy benzoic acid, also known as parabens. Suitable 
parabens include lower alkyl esters of 4-hydroxy benzoic acid, such as, for example, methyl 4
hydroxybenzoate (methyl parben), ethyl 4-hydroxybenzoate (ethyl paraben) and propyl 4-hydroxy
benzoate (propyl paraben).  
[00921 Skilled artisans will appreciate that solvents used to solubilize the MTZ in the high dosage 
mucoadhesive MTZ aqueous-based gels described herein may also have preservative properties. For 
example, benzyl alcohol has well known preservative properties. When used as a solvent in the novel 
solvent system, the preservative properties can be used to advantage. Indeed, gels including solvents 
with preservative properties need not include additional preservatives. Gels that utilize the 
preservative properties of solvents included in the solvent system should, in cases where the solvent 
may degrade and/or oxidize over time, include an amount of overage that takes into account the 
degradation and/or oxidation such that the gel retains an amount of undegraded and/or unoxidized 
solvent having, in addition to effective MTZ-solubilizing properties, effective preservative properties 
after a desired period of time. For example, benzyl alcohol is known to oxidize to benzaldehyde, 
which does not have preservative properties. In embodiments of the high dosage MTZ gels described 
herein that employ benzyl alcohol as an MTZ solvent and as a preservative, an amount of benzyl 
alcohol should be included in the gel that not only solubilizes the MTZ, but that yields a preservative 
effect for the duration of the expected shelf life of the gel. Overage amounts of benzyl alcohol, or 
other solvents employed in the solvent system in part as preservatives, can be determined based upon 
the degradation and/or oxidation properties and kinetics of the particular solvent under the desired 
conditions of storage.  
[0093] Embodiments of high dosage mucoadhesive MTZ aqueous-based gels that include solvents 
having preservative properties may also include one or more additional preservatives, and/or 
preservatives designed to protect the solvent from degradation and/or oxidation. For example, in the 
case of benzyl alcohol, the high dosage mucoadhesive MTZ aqueous-based gels described herein may 
include one or more additional preservatives that have antioxidant properties, in part to protect the 
benzyl alcohol from oxidation. In a specific embodiment, high dosage mucoadhesive MTZ aqueous-

based gels comprising benzyl alcohol include one or more parabens as additional preservatives. In 
some specific embodiments the high dosage mucoadhesive MTZ aqueous-based gels comprise about 
0.1% by weight total parabens, and in some specific embodiments about 0.02% by weight methyl 
paraben and about 0.08% by weight propyl paraben.  
[0094] The high dosage mucoadhesive MTZ aqueous-based gels also include water, either in the 
form of pure water, or in the form of an aqueous buffer. Typically, the amount of water included in 
the gel will be less than about 70% by weight, more typically less than about 60% by weight, and in 
some specific embodiments in the range of about 45% to about 55% by weight.  
[0095] A specific exemplary high dosage mucoadhesive MTZ aqueous-based gel comprises: 
(a) at least 1.3% MTZ by weight; from about 1.2% to about 2% MTZ by weight; from about 
3% to about 1.5% MTZ by weight; or about 1.3% MTZ by weight and 
(b) one or more mucoadhesive gelling polymers.  
[00961 Another specific exemplary high dosage mucoadhesive MTZ aqueous-based gel comprises: 
(a) from about 1.2% to about 2% MTZ by weight, for example about 1.3% to about 1.5% 
MTZ by weight, and in a specific embodiment about 1.3% MTZ by weight; and 
(b) one or more mucoadhesive gelling polymers and 
(i) about 25% PEG 400 by weight; and/or 
(ii) about 2% benzyl alcohol by weight; and/or 
(iii) about 15% propane-1,2-diol by weight.  
[00971 Another specific exemplary high dosage mucoadhesive MTZ aqueous-based gel comprises: 
(a) about 1.3% MTZ by weight and 25% PEG 400 by weight; 
(b) about 1.3% MTZ by weight, about 25% PEG 400 by weight, and about 2% benzyl alcohol 
by weight; or

(c) about 1.3% MTZ by weight, about 25% PEG 400 by weight, about 2% benzyl alcohol by 
weight, and about 15% propane-1,2-diol by weight.  
6.3. Methods of Making Gels 
[00981 The high dosage mucoadhesive MTZ aqueous-based gels described herein may generally be 
prepared by dissolving the water-soluble components of the gel in water or buffer to yield an aqueous 
solution, mixing the components of the MTZ solvent system and dissolving the desired quantity of 
MTZ in the MTZ solvent system to yield an MTZ solution, mixing together the required amounts of 
the aqueous solution and MTZ solution, and adding the desired quantity of gelling agent to the 
mixture. Depending upon the gelling polymers used, it may be desirable to adjust the pH of the MTZ 
solution to within a specified range with acid and/or base prior to adding the gelling polymer(s), and 
then adjusting the pH of the resultant gel to within a desired specified range with acid or base.  
Specific methods for making high dosage mucoadhesive MTZ aqueous-based gels are provided in 
Example 2.  
6.4. Uses 
[0099] The high dosage mucoadhesive MTZ aqueous-based gels described herein can be used to 
topically administer MTZ in any context where such administration would be beneficial. In specific 
embodiments described further below, the gels can be advantageously used intravaginally to treat 
women suffering from or diagnosed with BV.  
[0100] As used herein, a woman is said to be "suffering from" or diagnosed with BV if she 
experiences one or more of the accepted symptoms, conditions or presentations associated with BV.  
Individuals with BV typically present with, among other things, an unpleasant "fishy smelling" off
white, thin and homogeneous vaginal discharge without an inflammatory response. Individuals also 
present with a reduction in the prevalence and concentration of Lactobacilli (especially hydrogen 
peroxide producing forms) and a concomitant increase in Gardnerella vaginalis, Mobiluncus spp., 
anaerobic Gram-positive rods (of the genera Bacteroides, Prevotella and Porphyromonas), 
Peptostreptococcus spp. and Mycoplasma hominis. Predisposing factors are non-white ethnicity, 
prior pregnancy, use of an IUD, sexual activity, new sexual partners, and recent antibiotic use. BV is 
also associated with concurrent trichomoniasis.

[0101] Criteria for establishing a clinical diagnosis of BV are provided in, among other articles, a 
draft FDA guidance titled, "Guidance for Industry: Bacterial Vaginosis- Developing Antimicrobial 
Drugs for Treatment," draft dated July, 1998, which is incorporated herein by reference in its entirety 
(hereafter the "FDA Guidance"). As per the FDA Guidance, a clinical diagnosis of BV includes the 
following observations: 
1. off-white (milky or gray), thin, homogeneous discharge with minimal or absent pruritus 
and inflammation of the vulva and vagina; 
2. the presence of "clue cells" in 20% of the total epithelial cells on microscopic 
examination of a saline "wet mount"; 
3. vaginal secretion pH of>4.5; and 
4. a fishy odor of the vaginal discharge with the addition of a drop of 10% KOH (i.e., a 
positive "whiff test").  
[01021 These observations are commonly referred to as "Amsel criteria," and women presenting all 
four criteria are referred to herein as "Amsel Positive." 
[0103] Women experiencing vaginosis thought to be BV also typically have a Gram's stain slide 
Nugent score of ?4. The Nugent score is based upon the weighted sum of the following three 
bacterial morphotypes score calculated from slide exam under oil immersion at 1000x magnification: 
* Lactobacillus: large Gram-positive rods 
e Gardnerella/Bacteroides pp.: Small Gram-variable coccobacilli/small 
Gram-negative Rods 
* Mobiluncus spp.: thin, curved, Gram variable rods 
[01041 The criteria for BV according to Nugent's criteria is a total score of>7; a score of 4-6 is 
considered intermediate and a score of 0-3 is considered normal. A score of 3 is considered by the 
FDA to be abnormal.  
[0105] Morphotypes are scored as the average number seen per oil immersion field (a minimum of 
10-20 fields should be examined). Each morphotype is then given a numerical score as follows:

= no morphotypes seen; 1+ = <1 morphotype per field; 2+ = 1 to 4 morphotypes per field; 3+ = 5 to 
morphotypes per field; and 4+ = >30 morphotypes per field. The total Nugent score is calculated 
by summing the score of the individual morphotypes. For more information about the Nugent scoring 
system, see Nugent et al., 1991, "Reliability of Diagnosing Bacterial Vaginosis is Improved by a 
Standardized Method of Gram Stain Interpretation," J Clin Micrbiol 29(2):297-301. A woman with a 
Nugent score of >4 is referred to herein as "Nugent Positive." 
[01061 In some embodiments, an individual who presents with at least 3 of the above Amsel criteria 
is considered to be suffering from and/or diagnosed with BV. In some embodiments, an individual 
who is Nugent Positive is considered to be suffering from and/or diagnosed with BV. In specific 
embodiments, an individual suffering from and/or diagnosed with BV is Amsel Positive. In still other 
specific embodiments, an individual suffering from and/or diagnosed with BV is both Amsel Positive 
and Nugent Positive.  
[0107] Preferably, an individual who is suffering from and/or diagnosed with BV will not have other 
vaginal infections, including but not limited to Chlamydia, trichomonas, gonorrhea, and Candida.  
Preferably, an individual who is suffering from and/or diagnosed with BV is not being treated for 
other vaginal infections, including but not limited to Chlamydia, trichomonas, gonorrhea, and 
Candida. In one embodiment, an individual who is suffering from and/or diagnosed with BV is being 
treated with fluconazole.  
[01081 The methods generally involve applying intravaginally to a woman suffering from and/or 
diagnosed with BV an amount of a high dosage mucoadhesive MTZ aqueous-based gel as described 
herein for a number of applications sufficient to provide a therapeutic benefit. As used herein, a 
"therapeutic benefit" is achieved when one or more of the symptoms of BV and/or one or more of the 
clinical manifestations of BV, including, for example, one or more of the Amsel criteria or the Nugent 
score, are ameliorated, eliminated, eradicated or improved. A treatment regimen can provide 
therapeutic benefit to a subject without curing the underlying BV condition.  
[0109] As used herein, a symptom or manifestation of BV is ameliorated if it is decreased in 
magnitude after therapy, or moves closer to a level considered normal. For example, the Amsel 
criteria are ameliorated if the vaginal discharge returns to normal; the number of clue cells in a wet 
mount is less than about 20% of vaginal epithelial cells, for example, less than about 19%, 18%, 17%, 
16%, 15%, 10%, 5% or even less; the pH of the vaginal secretion is reduced from about pH 4.7 to

about pH 5.3 prior to treatment to within a range of about pH 4.0 to about pH 4.5, for example, 
pH 4.3, pH 4.2, pH 4.1, or pH 4.0 after treatment; and/or the whiff test produces no appreciable amine 
or "fishy" odor. Symptoms of BV are considered eliminated or eradicated if the symptoms are no 
longer detectable using well-known detection means (see, e.g., the various detection means provided 
in the Examples section and those disclosed in the FDA Guidance).  
[0110] As used herein, a "therapeutically effective amount" refers to a treatment regimen with a high 
dosage mucoadhesive MTZ aqueous-based gel that provides therapeutic benefit.  
[0111] In some embodiments, an amount of high dosage mucoadhesive MTZ aqueous-based gel is 
applied for a number of applications sufficient to provide an improvement in at least one Amsel 
criteria, and preferably at least 2 or 3, and most preferably all 4 Amsel criteria, and/or a result in a 
Nugent score of less than 4.  
[0112] In some specific embodiments, an amount of a high dosage mucoadhesive MTZ aqueous
based gel is applied for a number of applications sufficient to yield a clinical cure. As used herein, a 
"clinical cure" is achieved when all four of the Amsel criteria are neutralized as noted below: 
1. original discharge characteristic of BV has returned to a normal physiological discharge 
which varies in appearance and consistency depending upon the menstrual cycle; 
2. a saline wet mount is negative for clue cells; 
3. the pH of vaginal secretion is pH <4.7, typically measured using pH paper that measure 
from pH 4.0 to pH 6.0; 
4. the whiff test is negative for any amine ("fishy") odor.  
[0113] In some specific embodiments, an amount of a high dosage mucoadhesive MTZ aqueous
base gel is applied for a number of applications sufficient to yield a bacteriological cure. As used 
herein, a "bacteriological cure" is achieved when a Nugent Score of <4, for example, a Nugent Score 
of 1, 2 or 3, or in the range of 0-3, is achieved.  
[0114] In still other specific embodiments, an amount of a high dosage mucoadhesive MTZ aqueous
based gel as described herein is applied for a number of applications sufficient to yield a therapeutic

cure. As used herein, a "therapeutic cure" is achieved when both a clinical cure and a bacteriological 
cure are achieved.  
[01151 In still other specific embodiments, an amount of high dosage mucoadhesive MTZ aqueous
based gel is applied for a number of applications sufficient for a physician to determine that no 
additional therapy is needed. In yet another specific embodiment, an amount of a high dosage 
mucoadhesive MTZ aqueous-based gel as described herein is applied for a number of applications 
sufficient to achieve any level of cure as defined in the FDA Guidance.  
[01161 In some specific embodiments, the amount of high dosage mucoadhesive MTZ aqueous
based gel applied in a single application contains from about 60 mg to about 100 mg MTZ. In some 
specific embodiments, the amount of high dosage mucoadhesive MTZ aqueous-based gel applied in a 
single application contains from about 60 mg to about 80 mg, or from about 60 mg to about 70 mg, 
MTZ. In some specific embodiments, the amount of high dosage MTZ aqueous-based gel applied in 
a single application contains about 65 mg MTZ.  
[01171 The frequency and duration of application can vary, and may depend upon the desired 
outcome. Generally, the gel is applied once per day for a period of one, two, three, four or five days.  
It has been found that significant therapeutic benefit is achieved with a single application of high 
dosage mucoadhesive MTZ aqueous-based gel containing about 65 mg MTZ. Accordingly, in some 
embodiments the gel is applied in a single application, i.e., in the absence of further application of the 
high dosage mucoadhesive MTZ aqueous-based gel. It has also been found that application of a high 
dosage mucoadhesive MTZ aqueous-based gel containing about 65 mg MTZ applied once per day for 
a period of five days yielded less incidence of BV recurrence than a similar course of treatment with 
FDA-approved 0.75 wt% metronidazole gel, and virtually no incidence of vulvovaginal candidiasis 
post therapy. Accordingly, in some embodiments the gel is applied once per day for a period of five 
days.  
[01181 As used herein, the term "recurrence" means the reappearance of at least one of the 
symptoms of BV, as defined herein, following treatment with a high dosage MTZ gel described 
herein such that a subject is diagnosed, at least a second time, with BV following the conclusion of 
treatment.

[0119] A "decrease in the incidence of recurrence" means an increase in the time to recurrence of 
symptoms of BV following the conclusion of treatment with a high dosage MTZ gel described herein 
as compared to time to historical recurrence observed with conventional 0.75 wt% MTZ gels, such as 
METROGEL VAGINAL@. In specific embodiments, a decrease in the incidence of occurrence 
means that symptoms of BV are not observed for a period of at least about 19 days, for example 
days, 21 days, 22 days, 23 days, 24 days, 25 days, 26 days, 27 days, 28 days, 29 days or more, 
following conclusion of treatment. No recurrence of symptoms of BV for a period of at least 29 days, 
for example, 30 days, 35 days, 40 days, 45 days, 50 days, 3 months, 6, months, 9 months, one year, or 
more, following the conclusion of treatment, suggests that there is no recurrence in a subject 
following conclusion of treatment.  
[0120] A "decrease in the incidence of recurrence" can also be defined relative to a study population.  
For example, a treatment regimen with a high dosage mucoadhesive MTZ aqueous-based gel as 
described herein that yields a statistically significant number of fewer women who experience 
symptoms of BV at 20 or more.days following treatment as compared to the number who report 
symptoms of BV at 20 or more days following treatment with conventional 0.75 wt% MTZ gels (such 
as, for example, METROGEL VAGINAL@) is considered a decreased incidence of recurrence of 
BV.  
[0121] For use, the high dosage mucoadhesive MTZ aqueous-based gels can be packaged in any 
form that is convenient for the desired mode of application. In specific embodiments useful for 
intravaginal application, the high dosage mucoadhesive MTZ aqueous-based gel is packaged in unit 
dosage form, as a specific example as a pre-filled, single dose syringe-type applicator.  
6.5. Additional Non-Limiting Aspects 
[0122] Additional non-limiting aspects of the high dosage mucoadhesive MTZ aqueous-based gel 
compositions and methods of using them to treat women suffering from and/or diagnosed with BV 
are provided below.  
6.5.1. Methods 
[01231 MI. A method of treating a subject suffering from and/or diagnosed with BV, comprising 
applying intravaginally to the subject a mucoadhesive aqueous-based gel comprising one or more 
mucoadhesive gelling polymers, about I wt% to about 2 wt% metronidazole (MTZ), and water,

wherein the amount of mucoadhesive aqueous-based gel applied in a single application contains from 
about 60 mg to about 100 mg MTZ.  
[01241 M2. The method of aspect M1, wherein the levels of MTZ from the mucoadhesive aqueous
based gel measured in the stratum corneum and receiver fluid in an in vitro Franz cell skin permeation 
experiment carried out with human cadaver skin are at least about 25-55-fold higher and at least about 
1-20-fold lower, respectively, when normalized for concentration, than the MTZ levels measured 
from METROGEL VAGINAL@.  
[01251 M3. The method of aspect M1, in which the mucoadhesive aqueous-based gel has a viscosity 
ranging from about 200,000 mPa to about 400,000 mPa, measured at 25 'C using the controlled shear 
rate method, a Bohlin CVO 100 rheometer and the rheometer settings of Table 11.  
[01261 M4. The method of aspect Ml, in which the mucoadhesive aqueous-based gel has a degree 
of mucoadhesion within about ±10% of that of MG33PB.  
[01271 M5. The method of aspect M1, in which the mucoadhesive aqueous-based gel comprises 
about 30 wt% to about 60 wt% water.  
[01281 M6. The method of aspect M1, in which the mucoadhesive aqueous-based gel is 
substantially free of dextrins, cyclodextrins, niacin, and niacinamide.  
[0129] M7. The method of aspect M1 in which the mucoadhesive aqueous-based gel is stable for a 
period of at least 6 months at 25 'C.  
[0130] M8. The method of any one of aspects M1-M7 in which the mucoadhesive aqueous-based 
gel includes about 1 wt% to about 3 wt% total mucoadhesive gelling polymers and about 40-45 wt% 
of a solvent system for the MTZ.  
[0131] M9. The method of aspect M8 in which the solvent system comprises one or more solvents 
having a saturated MTZ solubility at 25 'C of at least about 20 mg/g.  
[01321 M10. The method of aspect M9 in which the solvent system comprises one or more solvents 
having a saturated MTZ solubility at 25 'C of at least about 50 mg/g and optionally one or more 
solvents having a saturated MTZ solubility at 25 'C in a range of about 20 mg/g to about 25 mg/g.

[01331 Ml1. The method of aspect M1O in which the solvent system comprises one or more lower 
aromatic alcohols and optionally one or more lower aliphatic diols and/or one or more 
polyoxyalkylenes having a molecular weight ranging from about 200 to about 400 ("lower 
polyoxyalkylene").  
[0134] M12. The method of aspect M 11 in which the solvent system comprises one or more lower 
aromatic alcohols, one or more lower aliphatic diols, and/or one or more lower polyoxyalkylenes.  
[0135] M13. The method of aspect M12 in which the solvent system comprises one or more lower 
aromatic alcohols, one or more lower aliphatic diols, and one or more lower polyoxyalkylenes.  
[01361 M14. The method of any one of aspects M 11-M13 in which the one or more lower aromatic 
alcohols are selected from the group consisting of benzyl alcohol, phenoxyethanol, and mixtures 
thereof.  
[0137] M15. The method of any one of aspects M 1-M14 in which the one or more lower alkylene 
diols are selected from the group consisting of ethane-1,2-diol (ethylene glycol), propane-1,2-diol 
(propylene glycol), and mixtures thereof.  
[01381 M16. The method of any one of aspects M 1-M15 in which the one or more lower 
polyoxyalkylenes are selected from the group consisting of polyoxyethylene (polyethylene glycol), 
polyoxypropylene (polypropylene glycol), and mixtures thereof.  
[01391 M17. The method of any one of aspects Ml l-M16 in which one or more lower aliphatic 
diols and the one or more lower polyoxyalkylenes are included in the solvent system in a total lower 
aliphatic diol to total lower polyoxyalkylene weight ratio ranging from about 1:1 to about 1:2.  
[0140] M18. The method of any one of aspects M13-M17 in which the solvent system comprises 
about 3.5 wt% to about 5 wt% total lower aromatic alcohols, and about 95 wt% to about 95.5 wt% of 
a mixture of the one or more lower alkylene diols and the one or more lower polyoxyalkylenes.  
[01411 M19. The method of aspect M18 in which the weight ratio of total lower alkylene diols to 
total lower polyoxyalkylenes ranges from about 1:1 to about 1:1.67.

[01421 M20. The method of any one of aspects M8-M19 in which the solvent system consists of 
benzyl alcohol, propane-1,2-diol and PEG 400.  
[0143] M21. The method of any one of aspects M8-M20 in which the solvent system consists of 
about 3.5 wt% to about 5 wt% benzyl alcohol and about 95 wt% to about 96.5 wt% of a mixture of 
propane-1,2-diol and PEG 400, wherein the weight ratio of the propane-1,2-diol to PEG 400 ranges 
from about 1:1 to about 1:1.67.  
[01441 M22. The method of any one of aspects M1-M21 in which the mucoadhesive aqueous-based 
gel further comprises one or more preservatives.  
[0145] M23. The method of any one of aspects M1-M22 in which the one or more preservative is an 
ester of 4-hydroxy benzoic acid (a paraben).  
[0146] M24. The method of aspect M23 in which the one or more preservatives are selected from 
the group consisting of methyl 4-hydroxybenzoate (methylpamben), propyl 4-hydroxybenzoate 
(propylparaben), and mixtures thereof.  
[01471 M25. The method of any one of aspects M1-M23 in which the mucoadhesive aqueous-based 
gel has a pH in the range about pH 3.0 to about pH 5.0.  
[01481 M26. The method of aspect M25 in which the mucoadhesive aqueous-based gel has a pH of 
about pH 4.0.  
[0149] M27. The method of any one of aspects M1-M26 in which the one or more mucoadhesive 
gelling polymer is selected from the group consisting of a hydroxyethylcellulose, a carbomer, a 
polycarbophil, and mixtures thereof.  
[0150] M28. The method of any one of aspects M1-M27 in which the amount of mucoadhesive 
aqueous-based gel applied in a single application contains about 65 mg MTZ.  
[0151] M29. The method of any. one of aspects M1-M28 in which the mucoadhesive aqueous-based 
gel includes about 1 wt% to about 1.5 wt% MTZ.  
[01521 M30. The method of aspect M29 in which the mucoadhesive aqueous-based gel is applied 
once per day for a period of one to five days.

[01531 M3 1. The method of aspect M29 in which the mucoadhesive aqueous-based gel is applied 
once per day for a period of one day.  
[0154] M32. The method of aspect M29 in which the mucoadhesive aqueous-based gel is applied 
once per day for a period of five days.  
[0155] M33. The method of any one of aspects M1-M28 in which the mucoadhesive aqueous-based 
gel includes about 1.3 wt% MTZ.  
[0156] M34. The method of aspect M33 in which the mucoadhesive aqueous gel-based is applied 
once per day for a period of one to five days.  
[0157] M35. The method of aspect M33 in which the mucoadhesive aqueous-based gel is applied 
once per day for a period of one day.  
[0158] M36. The method of aspect M33 in which the mucoadhesive aqueous gel is applied once per 
day for a period of five days.  
[0159] M37. The method of any one of aspects M1-M7 in which the mucoadhesive aqueous-based 
gel comprises about 1.3 wt% MTZ, about 2 wt% polycarbophil AA-1, about 2 wt% benzyl alcohol, 
about 15 wt% propane-1,2-diol, about 25 wt% PEG 400, about 0.02 wt% methyl 4-hydroxybenzoate, 
and about 0.08 wt% propyl 4-hydroxybenzoate.  
[0160] M38. The method of aspect M37 in which the mucoadhesive aqueous-based gel is applied 
once per day for a period of one to five days.  
[0161] M39. The method of aspect M37 in which the mucoadhesive aqueous-based gel is applied 
once per day for a period of one day.  
[0162] M40. The method of aspect M37 in which the mucoadhesive aqueous-based gel is applied 
once per day for a period of five days.  
[0163] M41. The method of any one of aspects M37-M40 in which the amount of mucoadhesive 
aqueous-based gel applied in a single application contains about 65 mg MTZ.

[01641 M42. A method of treating a subject suffering from and/or diagnosed with BV, comprising 
applying intravaginally to the subject an amount of an aqueous-based gel for a number of applications 
sufficient to achieve a clinical cure, wherein the aqueous-based gel comprises one or more 
mucoadhesive polymers, about 1.3 wth MTZ, and water, and has one or more features or 
characteristics selected from the following group: 
(a) the levels of MTZ from the mucoadhesive aqueous-based gel measured in the stratum 
corneum and receiver fluid in an in vitro Franz cell skin permeation experiment carried out with 
human cadaver skin are at least about 25-55-fold higher and at least about 1-20-fold lower, 
respectively, when normalized for concentration, than the MTZ levels measured from METROGEL 
VAGINAL@; 
(b) a viscocity ranging from about 200,000 mPa to about 400,000 mPa, measured at 25 'C 
using the controlled shear rate ramp method, a Bohlin CVO 100 rheometer and the rheometer settings 
of Table 11; 
(c) a degree of mucoadhesion within about ±10% of that of MG33PB; 
(d) comprises about 30 wt% to about 60 wt% water; 
(e) is substantially free of dextrins, cyclodextrins, niacin and niacinamide; 
(f) is stable for a period of at least 6 months at 25 'C; and 
(g) includes about 1 wt% to about 3 wt% total mucoadhesive polymers and about 40-45 wt% 
of a solvent system for the MTZ.  
[0165] M43. The method of aspect M42 in which an amount of the aqueous-based gel is applied for 
a number of applications sufficient to achieve a therapeutic cure.  
[0166] M44. A method of treating a woman suffering from and/or diagnosed with BV, comprising 
applying intravaginally to the woman a single application of a mucoadhesive MTZ aqueous-based gel 
comprising about 1.3% by weight MTZ, about 1% to about 2% weight of one or more mucoadhesive 
gelling polymers, about 40% to about 50% weight of a solvent system for the MTZ, and about 50% to 
about 55% by weight water, where the solvent system comprises about 3% to about 5% by weight of

one or more solvents having a saturated MTZ solubility at 25 'C of at least about 50 mg/g and about 
95% to about 97% by weight of one or more solvents that collectively have a saturated MTZ 
solubility at 25 'C in the range of about 20 mg/g to about 25 mg/g, and wherein the amount of the 
mucoadhesive MTZ aqueous-based gel applied contains about 60 mg to about 100 mg MTZ.  
[0167] M45. The method of aspect M44 in which the amount of mucoadhesive MTZ aqueous-based 
gel applied contains about 65 mg MTZ.  
[0168] M46. The method of any one of aspects M43-M45 in which the one or more solvents having 
a saturated MTZ solubility at 25 0C of at least about 50 mg/g is benzyl alcohol.  
[0169] M47. The method of any one of aspects M43-M46 in which the one or more solvents that 
collectively have a saturated MTZ solubility at 25 'C in the range of about 20 mg/g to about 25 mg/g 
are each selected from the group consisting of a lower aliphatic diol and a lower polyoxyalkylene.  
[01701 M48. The method of any one of aspects M43-M47 in which the solvent system comprises 
about 3% to about 5% by weight benzyl alcohol and about 95% to about 97% by weight of a mixture 
of a lower aliphatic diol and a lower polyoxyalkylene, where the weight ratio of the lower aliphatic 
diol to lower polyoxyalkylene is in the range of about 1:1 to about 1:2.  
[01711 M49. The method of aspect M48 in which the weight ratio of the lower aliphatic diol to the 
lower polyoxyalkylene is about 1:1.67.  
[0172] M50. The method of any one of aspects M48-M49 in which the lower aliphatic diol is 
propane-1,2-diol and the lower polyoxyalkylene is PEG 400.  
[0173] M51. The method of any one of aspects M43-M50 in which the one or more mucoadhesive 
gelling polymers are each selected from the group consisting of a cross-linked acrylic acid polymer 
and a cellulosic polymer.  
[0174] M52. The method of any one of aspects M43-M51 in which the one or more mucoadhesive 
gelling polymers are each selected from the group consisting of a carbomer and a polycarbophil.  
[0175] M53. The method of any one of aspects M43-M52 in which the one or more mucoadhesive 
gelling polymer is a polycarbophil.

[0176] M54. The method of any one of aspects M43-M53 in which the mucoadhesive MTZ 
aqueous-based gel comprises about 1.3% by weight MTZ, about 2% by weight polycarbophil AA-1, 
about 2% by weight benzyl alcohol, about 15% by weight propane-1,2-diol, about 25% by weight 
PEG 400, about 0.1% by weight of one or more preservatives, and about 54.6% by weight water.  
[0177] M55. The method of M54 in which the one or more preservatives are each a paraben.  
[0178] M56. The method of aspect M55 in which the one or more preservatives are methylparaben 
and propylparaben.  
[0179] M57. The method of any one of aspects M43-M56 in which the mucoadhesive MTZ 
aqueous-based gel comprises about 1.3% by weight MTZ, about 2% by weight polycarbophil AA-1, 
about 2% by weight benzyl alcohol, about 15% by weight propane-1,2-diol, about 25% by weight 
PEG 400, about 0.08% by weight methylparaben, about 0.02% by weight propylparaben, and about 
54.6% by weight water.  
[0180] M58. A method of treating a subject suffering from and/or diagnosed with BV with a single 
application of a composition suitable therefor, comprising applying intravaginally to the subject a 
mucoadhesive aqueous-based gel comprising one or more mucoadhesive gelling polymers, water, and 
about 1.3 wt% MTZ, wherein the amount of mucoadhesive aqueous-based gel applied in the single 
application contains about 65 mg of MTZ; and the single application is sufficient to treat or cure the 
BV in the complete or substantial absence of further treatments or applications.  
[0181] M59. A method of treating a subject suffering from and/or diagnosed with BV, comprising 
applying intravaginally to the subject a single administration of a mucoadhesive aqueous-based MTZ 
gel, wherein the mucoadhesive aqueous-based MTZ gel comprises one or more mucoadhesive gelling 
polymers, about 1.3% by weight MTZ, and water, and the amount of mucoadhesive aqueous-based 
gel applied in the single administration contains about 65 mg MTZ.  
[0182] M60. A method of treating a subject suffering from and/or diagnosed with BV, comprising 
applying intravaginally to the subject a mucoadhesive aqueous-based MTZ gel, wherein (i) the 
mucoadhesive aqueous-based MTZ gel comprises one or more mucoadhesive gelling polymers, about 
1.3% by weight MTZ, and water, (ii) the amount of the mucoadhesive aqueous-based MTZ gel

applied contains about 65 mg MTZ, and (iii) the mucoadhesive aqueous-based MTZ gel is applied a 
single time without further applications.  
[01831 M61. A method of treating a subject suffering from and/or diagnosed with BV, comprising 
applying intravaginally to the subject a mucoadhesive aqueous-based MTZ gel, wherein (i) the 
mucoadhesive aqueous-based MTZ gel comprises one or more mucoadhesive gelling polymers, about 
1.3% by weight MTZ and water, (ii) the amount of the mucoadhesive aqueous-based gel applied in a 
single application contains about 65 mg MTZ, and (iii) the mucoadhesive aqueous-based MTZ gel is 
applied once per day for a total of one day.  
[01841 M62. A method of treating a subject suffering from and/or diagnosed with BV, comprising 
applying intravaginally to the subject a mucoadhesive aqueous-based MTZ gel at least once a day for 
a period of 5 total days, wherein (i) the mucoadhesive aqueous-based MTZ gel comprises one or more 
mucoadhesive gelling polymers, about 1.3% by weight MTZ, and water, and (ii) the amount of the 
mucoadhesive aqueous-based MTZ gel applied in a single application contains about 65 mg MTZ.  
[0185] M63. A method of treating a subject suffering from and/or diagnosed with BV, comprising 
applying intravaginally to the subject a single application of an amount of a mucoadhesive aqueous
based MTZ gel sufficient to cure the BV, wherein the mucoadhesive aqueous-based MTZ gel 
comprises one or more mucoadhesive gelling polymers, about 1.3% by weight MTZ, and water.  
[0186] M64. The method of any one of aspects M58-M63 in which the mucoadhesive aqueous
based MTZ gel is a gel according to any one of aspects CI-C32, below.  
6.5.2. Compositions 
[0187] Cl. A mucoadhesive aqueous-based gel comprising about 1 wt% to about 2 wt% MTZ, 
about 1 wt% to about 3 wt% of one or more mucoadhesive gelling polymers, about 30 wt% to about 
wt% of a solvent system for the MTZ, and water, where the levels of MTZ from the mucoadhesive 
aqueous-based gel measured in the stratum corneum and receiver fluid in an in vitro Franz cell skin 
permeation experiment carried out with human cadaver skin are at least about 25-55-fold higher and 
at least about 1-20-fold lower, respectively, when normalized for concentration, than the MTZ levels 
measured from METROGEL VAGINAL@.

[01881 C2. A mucoadhesive aqueous-based gel comprising about 1 wt% to about 2 wt% MTZ, 
about 1 wt% to about 3 wt% of one or more mucoadhesive gelling polymers, about 30 wt% to about 
wt% of a solvent system for the MTZ, and water, wherein the mucoadhesive aqueous-based gel 
has a viscocity ranging from about 200,000 mPa to about 400,000 mPa, measured at 25 'C using the 
controlled shear rate method, a Bohlin CVO 100 rheometer and the rheometer settings of Table 11.  
[01891 C3. A mucoadhesive aqueous-based gel comprising about 1 wt% to about 2 wt% MTZ, 
about 1 wt% to about 3 wt% of one or more mucoadhesive gelling polymers, about 30 wt% to about 
wt% of a solvent system for the MTZ, and water, wherein the mucoadhesive aqueous-based gel 
has a degree of mucoadhesion within about ±10% of that of MG33PB.  
[0190] C4. A mucoadhesive aqueous-based gel comprising about 1 wt% to about 2 wt% MTZ, 
about 1 wt% to about 3 wt% of one or more mucoadhesive gelling polymers, about 30 wt% to about 
wt% of a solvent system for the MTZ, and about about 30 wt% to about 60 wt% water.  
[01911 C5. A mucoadhesive aqueous-based gel comprising about I wt% to about 2 wt% MTZ, 
about 1 wt% to about 3 wt% of one or more mucoadhesive gelling polymers, about 30 wt% to about 
wt% of a solvent system for the MTZ, and water, wherein the mucoadhesive aqueous-based gel is 
substantially free of dextrins, cyclodextrins, niacin and niacinamide, and optionally also surfactants.  
[0192] C6. A mucoadhesive aqueous-based gel comprising about 1 wt% to about 2 wt% MTZ, 
about 1 wt% to about 3 wt% of one or more mucoadhesive gelling polymers, about 30 wt% to about 
wt% of a solvent system for the MTZ, and water, wherein the mucoadhesive aqueous-based gel is 
stable for a period of at least 6 months at 25 0C.  
[0193] C7. The gel of any one of aspects C1-C6 in which the mucoadhesive aqueous-based gel 
includes about 1 wt% to about 3 wt% total mucoadhesive gelling polymer and about 40-45 wt% of a 
solvent system for the MTZ.  
[0194] C8. The gel of aspect C7 in which the solvent system comprises one or more solvents having 
a saturated MTZ solubility at 25 C of at least about 20 mg/g.  
[0195] C9. The gel of aspect C8 in which the solvent system comprises one or more solvents having 
a saturated MTZ solubility at 25 'C of at least about 50 mg/g and optionally one or more solvents 
having a saturated MTZ solubility at 25 'C in a range of about 20 mg/g to about 25 mg/g.

[01961 C1O. The gel of aspect C9 in which the solvent system comprises one or more lower 
aromatic alcohols, and optionally one or more lower aliphatic diols and/or one or more 
polyoxyalkylenes having a molecular weight ranging from about 200 to about 400 ("lower 
polyoxyalkylene").  
[01971 Cl1. The gel of aspect C1O in which the solvent system comprises one or more lower 
aromatic alcohols, one or more lower aliphatic diols, and/or one or more lower polyoxyalkylenes.  
[01981 C12. The gel of aspect CI in which the solvent system comprises one or more lower 
aromatic alcohols, one or more lower aliphatic diols, and one or more lower polyoxyalkylenes.  
[01991 C13. The gel of any one of aspects C1O-C12 in which the one or more lower aromatic 
alcohols are selected from the group consisting of benzyl alcohol, phenoxyethanol, and mixtures 
thereof.  
[02001 C14. The gel of any one of aspects CO-C13 in which the one or more lower alkylene diols 
are selected from the group consisting of ethane-1,2-diol (ethylene glycol), propane-1,2-diol 
(propylene glycol), and mixtures thereof.  
[02011 C15. The gel of any one of aspects C1O-C14 in which the one or more lower 
polyoxyalkylenes are selected from the group consisting of polyoxyethylene (polyethylene glycol), 
polyoxypropylene (polypropylene glycol), and mixtures thereof.  
[0202] C16. The gel of any one of aspects CO-C15 in which one or more lower aliphatic diols and 
the one or more lower polyoxyalkylenes are included in the solvent system in a total lower aliphatic 
diol to total polyoxyalkylene weight ratio ranging from about 1:1 to about 1:2.  
[0203] C17. The gel of any one of aspects C1O-C16 in which the solvent system comprises about 
3.5 wt% to about 5 wt% total lower aromatic alcohols and about 95 wt% to about 95.5 wt% of a 
mixture of the one or more lower alkylene diols and the one or more lower polyoxyalkylenes.  
[0204] C18. The gel of aspect C17 in which the weight ratio of total lower alkylene diols to total 
lower polyoxyalkylenes is about 1:1.67.

[0205] C19. The gel of any one of aspects C1O-C18 in which the solvent system consists of benzyl 
alcohol, propane-1,2-diol and PEG 400.  
[0206] C20. The gel of any one of aspects C1O-C19 in which the solvent system consists of about 
3.5 wt% to about 5 wt% benzyl alcohol and about 95 wt% to about 96.5 wt% of a mixture of propane
1,2-diol and PEG 400, wherein the weight ratio of the propane-1,2-diol to PEG 400 ranges from about 
1:1.67 to about 1:1.  
[02071 C21. The gel of any one of aspects C1-C20 which further comprises one or more 
preservatives.  
[0208] C22. The gel of any one of aspects C1-C21 in which the one or more preservative is an ester 
of 4-hydroxy benzoic acid (a paraben).  
[02091 C23. The gel of aspect C22 in which the one or more preservatives are selected from the 
group consisting of methyl 4-hydroxybenzoate (methylparaben), propyl 4-hydroxybenzoate 
(propylparaben), and mixtures thereof.  
[02101 C24. The gel of any one of aspects Cl-C23 which t has a pH in the range about pH 3.0 to 
about pH 5.0.  
[02111 C25. The gel of aspect C24 which has a pH of about pH 4.0.  
[0212] C26. The gel of any one of aspects Cl-C25 in which the one or more mucoadhesive gelling 
polymers are selected from the group consisting of a hydroxyethylcellulose, a carbomer, a 
polycarbophil, and mixtures thereof.  
[0213] C27. The gel of any one of aspects Cl-C6 in which the mucoadhesive aqueous-based gel 
comprises about 1.3 wt% MTZ, about 2 wt% polycarbophil AA-1, about 2 wt% benzyl alcohol, about 
wt% propane-1,2-diol, about 25 wt% PEG 400, about 0.02 wt% methyl 4-hydroxybenzoate, and 
about 0.08 wt% propyl 4-hydroxybenzoate.  
[0214] C28. A mucoadhesive aqueous-based gel comprising about 1.3 wt% MTZ, about 1 wt% to 
about 3 wt% of one or more mucoadhesive gelling polymesr and about 40 wt% to about 45 wt% of a 
solvent system for the MTZ, where the solvent system comprises benzyl alcohol, propane-1,2-diol,

and PEG 400 and wherein the gel is stable for a period of 18 months when stored at a temperature in 
the range of about 25 'C to about 40 'C.  
[0215] C29. The gel of aspect C28 in which the one or more mucoadhesive gelling polymers are 
selected from the group consisting of cross-linked acrylic acid polymers and cellulosic polymers.  
[0216] C30. The gel of aspect C29 in which the cross-linked acrylic acid polymers are selected from 
the group consisting of carbomers and polycarbophils.  
[0217] C3 1. The gel of any one of aspects C29-C30 in which the cellulosic polymers are selected 
from the group consisting of hydroxyethyl cellulose, hydroxypropyl cellulose, and hydroxypropyl 
methyl cellulose.  
[0218] C32. The gel of any one of aspects C29-C31 which comprises about 2 wt% total 
mucoadhesive gelling polymers.  
6.5.3. Uses 
[0219] Ul. The use of a mucoadhesive aqueous-based gel according to any one of aspects C1-C32 
for the treatment of a woman suffering from and/or diagnosed with BV.  
[0220] U2. The use of aspect Ul in which the mucoadhesive aqueous-based gel is applied 
intravaginally for a number of applications sufficient to yield a bacteriological cure, a clinical cure, or 
a therapeutic cure.  
[0221] U3. The use according to any one of aspects U1-U2 in which the amount of mucoadhesive 
aqueous-based gel applied in a single application contains about 60 mg to about 100 mg MTZ.  
[0222] U4. The use of any one of aspects U 1 -U3, in which the amount of mucoadhesive aqueous
based gel applied in a single application contains about 65 mg MTZ.  
[0223] U5. The use of any one of aspects UI-U4, in which the mucoadhesive aqueous-based gel is 
applied intravaginally once per day for a period of from one to five days.  
[0224] U6. The use of any one of aspects U 1-U5, in which the mucoadhesive aqueous-based gel is 
applied intravaginally once per day for a period of one day.

[02251 U7. The use of any one of aspects U 1-U5, in which the mucoadhesive aqueous-based gel is 
applied once per day for a period of five days.  
6.5.4. Unit Dosage Forms 
[02261 D1. A unit dosage form of a high dosage mucoadhesive MTZ aqueous-based gel suitable for 
intravaginal application, comprising an amount of a gel according to any one of aspects C1 -C32 
containing about 65 mg to about 100 mg MTZ packaged in a container suitable for intravaginal 
application.  
[0227] D2. The unit dosage form of aspect Dl which includes an amount of a gel containing about 
mg MTZ.  
[0228] Unless otherwise defined, all technical and scientific terms used herein have the same 
meaning as commonly understood by one of ordinary skill in the art to which the various inventions 
described herein belong. Although methods and materials similar or equivalent to those described 
herein can be used in the practice or testing of the disclosed inventions, suitable methods and 
materials are described below. All publications, patent applications, patents, and other references 
mentioned herein are incorporated by reference in their entirety. In case of conflict, the present 
specification, including definitions, will control. In addition, the materials, methods, and examples 
are illustrative only and not intended to be limiting.  
7. EXAMPLES 
[0229] Having now generally described the inventions of the disclosure, the same will be more 
readily understood through reference to the following Examples, which are provided by way of 
illustration, and are not intended to limit the scope of the inventions described herein.  
Example 1: Exemplary Solvents Useful for Solvent Systems 
[02301 The solubility of MTZ in a variety of solvents at 25 *C was determined to identify solvents 
useful for solubilizing MTZ at the concentrations required for the high dosage mucoadhesive MTZ 
aqueous-based gels described herein. The saturated MTZ solubility at 25 'C of a number of solvents 
are provided in Table 1, below. Solvent systems useful for preparing high dosage mucoadhesive 
MTZ aqueous-based gels having desired concentrations of MTZ can be devised using these saturated 
solubilities for guidance. Additional solvents suitable for use with these (and other) solvents for

preparing high dosage mucoadhesive MTZ aqueous-based gels as described herein may be readily 
identified based upon their saturated MTZ solubilities. The saturated MTZ solubility at 25 'C in a 
number of solvent systems that have been mixed with an aqueous phase that are suitable for preparing 
high dosage mucoadhesive MTZ aqueous-based gels are provided in Table 2, below.  
Table 1 
Solubility at 25 *C (mg/g) Solubility at 25 "C (mg/g) 
(n=3, mean ± SEM) (n=1) 
Benzyl alcohol 72.69 
2 wt% aq. Benzyl alcohol 10.81 ± 0.040 
Deionized water 8.70 ± 0.09 9.37 
Ethanol 16.36 0.12 19.96 
Ethylene glycol 21.34 
Glycerol 8.35 
wt% aq. glycerol 7.62 0.19 
Propylene glycol 18.62 0.25 20.74 
PEG 400 18.79 1.23 24.78 
Phosphate buffer, 50 mM, pH 4 8.26 0.45 9.09 
Phosphate buffer, 50 mM, pH 5 9.13 
Phosphate buffer, 50 mM, pH 6 8.57 0.05 9.10 
Phosphate buffer, 50 mM, pH 7 9.07 
tetraglycol 29.65 
wt% aq. Lutrol@ F127 9.15 0.09 
1 wt% aq. polysorbate 60 9.72 0.08

C) C>C)C 
0C6 C> 6 I 
N =n 
kf I n 
kn0n00 
N I I I . 0 n 
u En 
000E 
Cl E5 C) 
000 = 
000 P.tOo

Example 2: Exemplary High Dosage Mucoadhesive MTZ Aqueous-Based Gels 
[02311 A number of exemplary high dosage mucoadhesive MTZ aqueous-based gels containing 
different quantities of MTZ and utilizing a variety of different solvent systems were prepared and 
subjected to a variety of different homogeneity, rheological, stability, biological and clinical tests as 
described in later examples. All gels were prepared using a similar process, described below.  
[0232] Preparation of Gels. Required amounts of preservative(s), for example methyl paraben and 
propyl paraben, were weighed into a Duran* bottle followed by the aqueous phase (phosphate buffer 
or deionized water). The contents were thoroughly mixed to dissolve the preservatives. The 
remaining solvents (e.g., benzyl alcohol, ethanol, propylene glycol and PEG 400) were weighed into a 
separate Duran* bottle and mixed thoroughly followed by the required amount of metronidazole. The 
Duran* bottle was then placed in a water bath at 55 'C and stirred continuously until the 
metronidazole dissolved. The Duran* bottle was removed from the water bath, placed at room 
temperature and mixing was continued until the solution equilibrated to room temperature. The 
preservative solution was then added to the MTZ solution under constant stirring. The required 
amount of gelling agent was weighed into a weighing boat and added to the above solution under 
constant stirring and stirred until the gelling agent fully hydrated. Care was taken to mix the contents 
thoroughly to ensure homogeneity.  
[0233] For gels utilizing pH-sensitive or dependent gelling polymer, the pH of the MTZ solution can 
be adjusted to value within the optimal range for gelling prior to adding the gelling polymer, and the 
pH of the gel adjusted as need thereafter.  
[02341 Preparation of Placebo Gels. In several Experiments discussed herein, placebo gels are used 
as comparators or as controls. Placebo gels were prepared as described above. For the placebos, the 
MTZ was omitted and replaced with an equivalent wt% of water or buffer, depending upon the 
aqueous phase used for the active gel.  
[02351 Preparation of Phosphate Buffer pH 4. Disodium hydrogen phosphate dihydrate (3.9 g) is 
weighed into a 500 ml Duran* bottle and 450 ml of deionized water is added. The solution is mixed 
thoroughly to dissolve the buffer salt. The pH of the solution is adjusted to pH 4 using o-phosphoric 
acid and made up to volume with deionized water in a 500 ml volumetric flask.

[0236] The composition of various exemplary gels containing 1.5 wt% MTZ, 2.0 wt%, 1.3 wt% and 
1.18% MTZ are provided in Tables 3, 4, 5 and 6, respectively, below.  
[02371 Formulations MGO3, MGO4, MG08 and MGO9 listed in Table 3 formed clear thick pale 
yellow colored gels while MG26 formed a white cream gel. An ideal pH for the Carbomers, 
polycarbophil AA-1 and Carbomer 974P, to form a gel is neutral. Because the desired pH of gels for 
intravaginal application is approximately pH 4, high amounts of these gelling agents were used as 
compared to HEC. MG03 contained p-hydroxypropyl cyclodextrin as a solubilizing agent

Example 3: Mucoadhesive Properties of the Exemplary Gels 
[02381 The mucoadhesive properties of two exemplary high dosage mucoadhesive MTZ gels 
(MG32PB and MG33PB) were tested using two different methods: adherence to isolated porcine 
gastric mucosa and rheological measurements in the presence and absence of mucin. The methods 
and results are described below.  
a. Mucoadhesion Using Isolated Porcine Gastric Mucosa 
[0239] Methods. For the experiments, a small section (15 x 10 cm) of fresh porcine gastric mucosa 
was mounted on a slope at 100 angle and rinsed with pH 4 buffer for 10 min with the aid of a 
peristaltic pump. A small aliquot (50 p1) of test gel was spread on the mucosal membrane at the top 
of the slope and left for 10 min. The pump was then switched on and buffer collected after t = 1, 2, 3, 
4, 5, 10 and 15 min into individual vials at each time point. A blank sample without any test gel was 
also analyzed for any background or interference. The samples were filtered through 0.45 [tm PVDF 
syringe filters and analyzed by HPLC. The rate of loss of MTZ from the mucosal membrane was 
plotted against time for each test gel and the resultant data compared to determine the relative 
mucoadhesion of each test gel. A second experiment was also performed with sampling time points 
of 15 s intervals over 5 min.  
[02401 Results. The data are shown in FIGS. 1 and 2. The results show that MG32PB has 
marginally better mucoadhesivity than MG33PB as determined by the amount of metronidazole 
remaining on the mucosa at each time point.  
b. Rheological Measurements 
[02411 Methods. Mucin was weighed into a glass vial followed by the gel under investigation. A 
magnetic follower was placed in the sample and the sample mixed until all the mucin hydrated.  
Rheological parameters of the test gel with and without mucin were analysed using an oscillation 
experiment (Bohlin CVO rheometer). An amplitude sweep followed by a frequency sweep using 
corresponding placebo gels without mucin was initially carried out to determine the linear viscoelastic 
region. The parameters used to determine the frequency sweep for the gels are given in Table 7.

Table 7 
Rheometer Settings For Determining Frequency Sweep 
Parameter Setting 
Measurement type/diameter Parallel plate/40 mm 
Gap size 1000sLm 
Temperature mode Isothermal 25 'C 
Thermal equilibration time 60 s 
Shear mode Controlled stress 
Stress Fixed at 4 Pa 
Frequency sweep range 5-20 Hz 
Frequency increment step 0.15 Hz 
[0242] Test gel (about 1 g) was placed on the bottom plate of the rheometer fitted with a parallel 
plate. The lower plate was raised so as to trap the sample in the pre-determined gap. The sample was 
then subjected to a series of sinusoidal oscillations from 5 to 20 Hz in 0.15 Hz increments. The 
applied torque (4 Pa) was previously determined to be in the linear viscoelastic region for both the 
highest and the lowest frequency. Each gel was tested three times. At the end of each run, Bohlin 
computer software (version 6.50.5.7) was used to determine G', the elastic or storage modulus. The 
data obtained for each parameter was plotted as a function of frequency and the mean values of G' 
calculated at a fixed frequency of 10 Hz. Using the mean G' value of the active gel with mucin 
compared to the mean G' value of the active gel without mucin, the AG' and log ratio of G' with and 
without mucin were calculated.  
[02431 Results. Addition of mucin, which is also a polymer, increased the elastic modulus of the test 
gels as determined by AG' (Table 8). It is assumed that a higher value for log G' ratio correlates to 
more interaction with mucin and therefore better mucoadhesion. However, this increase could be 
dependent on the inherent interaction between the gelling polymer used for the preparation of gel and 
mucin. The log G' ratio, which is the ratio of log G' of the test gel with and without mucin gives an 
insight into the increase of viscoelastic nature of the formulation.

Table 8 
Mucoadhesion of Exemplary Gels MG32PB and MG33PB 
(determined by the effect of mucin on gel) 
Gel AG' Log G' ratio 
1 " run (n=1) 2"d run (n=3) 1" run (n-1) 2"d run (n=3) 
MG32PB 265.80 228.27 ± 13.35 0.049 0.041 ± 0.002 
MG33PB 150.65 173.59 34.02 0.025 0.31 0.006 
Example 4: Short-Term Shelf Stability of the Exemplary Gels 
[02441 Various different embodiments of exemplary high dosage mucoadhesive MTZ aqueous-based 
gels were tested for short-term (4 week) shelf stability at 25 'C and 45 'C. Gels were stored in 
Vindon Scientific stability cabinets in sealed amber vials. Parameters tested included homogeneity 
(visual and microscopic observation for presence of crystals and/or particulates), MTZ stability, 
preservative efficacy, viscosity and pH. The stability time points tested were t--0, 2 and 4 weeks at 
± 2 0C at 60 ± 5% RH and 40 ±2 'C at 75 ± 5% RH. Placebo gels without MTZ were also stored 
for the same duration and assessed for physical and chemical stability.  
[02451 To access MTZ stability, MTZ was extracted from the gel and analyzed by HPLC Method 1 
(parameters in Table 9, below). For the extraction, approximately 0.5 g gel was placed in a 50 mL 
volumetric flask. Approximately 30 mL of HPLC mobile phase 65:35 methanol/60 mM phosphate 
buffer (prepared as below) was added and the mixture vortexed until the gel was observed to have 
dispersed into solution. The solution was made up to volume with HPLC mobile phase. For HPLC 
analysis, an aliquot was filtered through a 0.45 jim PTFE syringe filter, discarding the first 2 ml. The 
remaining filtrate was analyzed by HPLC Method 1.

Table 9 
HPLC Method 1 
HPLC System Waters 2695D Alliance HPLC System 
Waters 996 Photo-diode array detector 
Waters Empower Data processing Software (version 5.00.00.00) 
Column Zorbax C8 5 pm, 250 x 4.6 mm 
Guard Column Zorbax C8 5 pm 20 x 3.9 mm guard column 
Detection 254 nm 
Sample Temperature 250 C 
Column Temperature 25 0C 
Flow Rate 1 ml/min 
Mobile Phase 65:35 methanol/60 mM phosphate buffer 
Injection Volume 20 pl 
Run Time 10 min 
Needle Wash 65:35 methanol/water 
Pump Wash 60:40 methanol/water 
[0246] To prepare the mobile phase, 1.5g sodium phosphate monobasic and 1.3g sodium phosphate 
dibasic were weighed into a Duran* bottle and dissolved in 350 ml deionized water. The solution was 
mixed thoroughly, 650 ml methanol added, the resultant solution mixed thoroughly with a magnetic 
stirrer and filtered through a 0.22 ptm filter.  
[0247] For the HPLC analysis, the MTZ peak (retention time approx. 3.312 min at 254 nm detection) 
was integrated and compared to a control sample. The amount of MTZ remaining after storage was 
quantified as a percentage of the theoretical concentration (TC) at t-0. The measured concentration 
(MC) was determined using a calibration curve obtained with MTZ stock solutions of known 
concentrations (prepared by serial dilution of a I mg/ml stock).  
[02481 The physical stability of the gels was assessed using light microscopy (Leica DME SOP 
3091). The test gel was compared to a corresponding placebo control gel to assess the presence of 
particulates.  
[0249] Results. The percentage of MTZ recovered from the gels is provided in Table 10 below.  
MTZ was stable in all gels at all concentrations tested. A low recovery was observed in MG37PB, 
MG42PB and MG43PB from the 4 week 25 'C samples. However, the recovery from the same gels 
stored at 40' C was 100%, suggesting a possible extraction/weighing error for the 25 'C samples.  
The % peak purity for all samples was 100%.

Table 10 
4-Week Short-Term Stability of Exemplary Gels at 25 *C and 40 *C (n=3, mean ± SD) 
Percentage Recovery of MTZ Compared to Control 
t=0 t=2wk25*C t=2wk40*C t=4wk25 C t=4wk40*C 
MG32-1.3% 103.20 0.66 n/a 100.53 0.17 n/a 101.12 0.36 
MG33-1.3% 105.04 0.35 n/a 100.74 0.32 n/a 100.98 0.31 
MG34-1.3% 103.33 0.64 n/a 100.73 0.10 n/a 101.64 0.43 
MG35-1.3% 102.54 0.09 n/a 100.86 0.36 n/a 101.18 0.31 
MG36-1.3% 103.49± 1.17 n/a 101.09 0.68 n/a 101.01 0.64 
MG37-1.3% 103.46 0.64 n/a 94.15 5.88 n/a 101.14 0.15 
MG42-1.18% 102.99 1.72 n/a 92.44 0.18 n/a 101.58 0.80 
MG43-1.18% 102.70 0.81 n/a 92.64 0.99 n/a 101.30 0.77 
MG44-1.18% 103.39 0.56 n/a 98.34 4.17 n/a 101.27 0.50 
MG03-1.5% 104.76 0.48 106.48 1.01 105.86 1.37 n/a * 105.78 0.86 
MG04-1.5% 104.74 ± 0.48 105.45 ± 2.28 104.09 ± 0.50 106.27 ± 0.13 106.01 ± 0.34 
MG08-1.5% 101.31 ± 2.67 99.02 ± 1.35 98.39 ± 0.78 100.40 ± 1.28 98.43 ± 0.81 
MG26-1.5% 104.51 0.56 103.34 0.52 103.97 1.26 104.45 0.23 103.97 1.11 
MG18-2.0% 102.42 ± 0.96 103.51 ± 0.38 104.21 ± 1.00 104.71 ± 0.63 104.94 0.23 
MG21-2.0% 103.67 + 0.52 104.81 + 0.63 105.46 + 0.66 106.40 + 0.11 106.00 + 0.17 
MG23-2.0% 104.95 + 0.52 106.18 + 0.47 106.35 ± 1.34 107.38 + 0.23 105.78 + 0.98 
MG24-2.0% 103.07 + 0.41 102.78 + 0.24 105.50 ± 1.39 105.21 + 0.39 103.92 + 1.19 
* Sample not analyzed due to microbial growth 
Example 5: Long-Term Shelf Stability of the Exemplary Gels 
[0250] Various different embodiments of exemplary high dosage mucoadhesive MTZ aqueous-based 
gels were tested for long-term stability, at 25 'C and 40 'C.  
[0251] For the study, 20g of each test gel was stored in a sealed vial at 25 + 2 'C/60 + 5% RH and 
+ 2 'C/75 + 5% RH. Back-up samples were also stored at -20 'C, 2-8 'C and 30 'C/65% RH for 
analysis upon failure of either real or accelerated time samples. Corresponding placebo gels without 
MTZ were stored along with the test gels.  
[02521 Gels were removed from the storage cabinets after 1, 2, 3, 6, 12 and 18 months and tested for 
physical and chemical stability using microscopic analysis and viscosity analysis, as described below.

[02531 Microscopic analysis. Gels were viewed under a light microscope (Leica* DME). A small 
sample of the gel was placed onto a microscope slide using a micro-spatula. The microscope slide 
was covered with a cover glass and the gel viewed using the 40x objective. Active gels were 
compared to placebo gels for the presence of crystals.  
[02541 If crystals were observed, the particle size was measured using the scale on a calibrated 
graticule (Olympus,* Objective Micrometer, 0.01 mm). The microscope was set up so that the 
camera (Nikon Cool Pix* 4500 digital camera) was attached to the relay lens of the microscope and 
the 40x objective lens was set into place to view the sample. Camera settings: Image size: 1280 x 
960 pixels, Image quality: Fine. Once a clear distinct view was obtained, pictures were taken (x400 
magnification).  
[0255] Viscosity Analysis. The rheology of the gels was measured at each time point (t = 0, 1, 2, 3, 
6, 12 and 18 months). A cone and plate measurement system is preferable for flow curve 
measurements as the shear rate is constant across the diameter of the truncated cone. Accordingly, a 
controlled shear rate ramp method was employed. A point on the flow curves at a shear rate of 
0.16 s- was used to compare each gel and the viscosity determined. The rheometer settings used are 
in Table 11 below: 
Table 11 
Rheometer settings for the controlled shear rate ramp 
Measurement type / diameter Cone and plate/ 40/40mm 
Gap size 150 pim 
Shear rate range From 0.001 - 1.0 s-1 
Duration shear rate 180 s 
Progression of shear rate increments Linear 
Temperature of sample 25 0C ± 0.1 0C 
Isothermal conditions Measurements forced to wait until sample at temperature, time 
out after 900 s 
Thermal equilibration time 0 s once temperature was 25 'C ± 0.1 before first 
measurements were made.  
[0256] Gels were also tested for MTZ content, benzyl alcohol content, paraben content, preservative 
efficacy and pH. With the exception of the 18 mos samples, the MTZ content was accessed as 
described above for the short-term stability samples. For the 18 mos samples, MTZ content was 
assessed as described below.

[0257] For the extraction, 0.5g 20 mg of gel was weighed into a 25 ml volumetric flask and diluted 
with approximately 20 ml of sample diluient (3:7 methanol / 10 mM KH2P0 4). The mixture was 
vortexed until the gel dispersed into solution (approximately 5 min). The solution was brought to 
volume with sample diluents and vortex mixed for approximately 1 minute. Approximately 14 ml of 
the sample was centrifuged at 3500 rpm for 10 min., the resultant supernatant filtered through a 
0.45 tm PTFE syringe filter, discarding the first 2 ml. The remaining filtrate was analyzed by HPLC 
Method 2 (parameters in Table 12, below). In addition to MTZ, the recovery of benzyl alcohol, 
methyl paraben and propyl paraben was also determined.  
Table 12 
HPLC Method 2 
HPLC System Waters 2695 Alliance HPLC System 
Waters 2996 Photo-Diode Array Detector 
Waters Empower Data Processing Software (version 6.10.01.00) 
Column Phenomenex luna C 18(2) 5pm, 250 x 4.6 mm lot number 479 458-61 
Guard Column Phenomenex Security guard C18, 4 x 3 mm 
Detection 254 nm 
Sample Temperature 25 ± 20 C 
Column Temperature 25 ± 2'C 
Flow Rate 1 mL/min 
Mobile Phase Mobile phase A: 0.01 M potassium dihydrogen phosphate dihydrate 
Mobile phase B: 100% methanol 
Gradient Time (min) Mobile phase A (%) Mobile phase B (%) 
80 20 
80 20 
18 28 72 
22 28 72 
23 80 20 
28 80 20 
Injection Volume 10 p1 
Run Time 28 min 
MTZ Retention Time 9.0 min 
Needle Wash 60:40 methanol (HPLC grade):deionized water (MilliQ 18.2 M9) 
Pump Wash 60:40 methanol (HPLC grade):deionized water (MilliQ 18.2 MI) 
[0258] Preservative efficacy testing was carried out in a manner consistent with the EP and US 
Pharmacopeia specifications. Inoculated samples were tested at t = 0 h, 24 h, 48 h, 7 days, 14 days, 
21 days and 28 days.

[02591 Gels corresponding to MG33PB but including reduced quantities of preservatives were tested 
for preservative efficacy. The test gels, Table 13, below, were prepared as described in Example 2.  
Table 13 
Composition of Variants of MG33PB 
MG33 (75%) MG33 (90%) 
MTZ 1.1700 1.170 
Purified water 54.940 55.255 
Polycarbophil AA-1 2.000 2.000 
Methyl paraben 0.072 0.060 
Propyl paraben 0.018 0.015 
Benzyl alcohol 1.800 1.500 
Propylene glycol 15.000 15.000 
PEG 400 25.000 25.000 
[02601 Placebo versions of gels MG33 (75%) and MG33 (90%) were also prepared.  
[0261] pH testing was carried out at t = 0, 1, 2, 3, 6, 12 and 18 months.  
[0262] Results. Table 14 shows the % recovery of MTZ from the gels. The percentage recovery of 
MTZ from the gels stored at 25 'C and 40 'C for 6 months is comparable to t=0 data. The % peak 
purity for all the gels is found to be 100%, indicating that MTZ is stable in all the gels tested. The 
percentage recovery of MTZ from MG33PB and MG32PB stored at 25 'C and 40 'C for 18 months is 
comparable to t=O data.

trn o"N C D 0 C D tfn w l ~ C Cd Cd 
C D, Cl N - l 
-H -H -H 
en - 0 " l c ~ -~ ~~ 
~6666 666c 
- m.O 0 m~ 00 D -t 0 - tr
0o N~ =o I'D C 0 '-~ C) 
~ ~ C) O 6 00 c= C 6 
tn M N C'\ C C) - "D 0 
C 5Q C>~ C> C) C) C) C) l O ) C = 
m m~ m~ C> 0 VN Lc > w a3 -d -C 
kn Cl- -) N ON 00 
-fl - - - - - 0 
en .00 N 0 ClC, , C-- m ON 
rq N -00 , C0000 > 00-C, 
~ k Cl 00 Lrq ON0 0 ~~ I 
e4 0 l 0 - N 00 0 , - 00 ON- 00L 
o ~Lr ==~-N d lC 00 
~~O O60 O CO c 
Cu~~ u0ON 0 tf -0 
~ L~00 

[0263] Physical stability of metronidazole gel formulations. Gels placed at 25 'C and 40 'C were 
visually and microscopically assessed for the presence of any particulates or crystals after 6 months.  
Although the gels were observed to be physically stable, there was a small change in color from a 
very pale yellow to pale yellow in all active gels after 6 months of storage at 40'C. This was absent 
in the corresponding placebo formulations (Table 17). Small differences in pH were observed in 
storage. However, no large shift in pH was observed in the active gels, indicating the gels are stable 
(Table 15) after 6 months.  
[0264] Flow curves were used to measure the viscosity of the gels. The point on the flow curves at 
which the viscosities of the gels were compared is at a shear rate of 0.16 s-1 (Table 11). After the 
readings (n=2) were taken at t-0, the curves were examined and a point of comparison selected. All 
of gels exhibited pseudoplastic behavior or shear thinning, i.e., as the shear rate increased, the 
viscosity decreased. As the shear rate is increased the instantaneous viscosity of the gels became 
more and more similar to each other such that there was no longer a marked difference between the 
viscosities of each gel. A point on the curve was chosen for comparison between the gels where all of 
the flow curves are different. The viscosity was calculated using the interpolation of the two closest 
shear rates above and below 0.16 s-'. All gels after 6 months storage at 25 'C and MG33PB at 25 'C 
up to 18 months were observed to show small variability in viscosity, generally constant between 
each time point up to 18 months (Table 16). At 40 'C storage, a drop in viscosity was observed, 
however this was more significant for the placebo gels than the active gels.  
[02651 The back-up active gels stored at 2-8 'C for 6 months were also inspected for crystal 
formation, as were placebo gels stored under the same conditions as their corresponding best gels.  
Large crystals were observed in gels MG32PB and MG35PB. Large sheet like crystals also formed 
gels MG33PB and MG36PB. A single small crystal formed in gels MG34PB and MG37PB. These 
data indicate that storage at 2-8 'C is not recommended for the high dosage mucoadhesive MTZ 
aqueous-based gels. Storage at 25 'C or 40 'C is more suitable, as crystal formulation was not 
observed at these temperatures.  
[0266] Observations of the physical appearance of placebo and test formulations stored for 6 mos at 
'C and 40 *C is provided in Table 17, below.

- N Cd C Cd m 0 - M MC M 
00 
. 0 C -4O N MM 0~ . o clO 'd cq C,3 'd k0 0 V.) tr,; 
od M 00 Cd u ~C ~C 
0 zI 0 0 
U 
0~ I 000 hA m1 0000 
u u 
w0 all O , ON . 0 0 0 0 . . 0 
'4 'It 0 00 0 ' ' 4 = - O - 0 
kn Un m m 
04 lO C ON u 4 ~C C ' 
ON 00 00 - N N 4-0 C> C0 CN N O 
el N -0 0 0 - ON Cl 0 
II" s

ol t- n k~n C; o -t-t 
No CN ON "o r 0 
cQ Cd Cd Cd CdC ~ C 
N ' 0 ON Il N m C-In N~ 
tn cd Cd 0000 
00i- C Nl N NZI a3 m M 00 3 
M -o 0N "t NN 
ontn\ ~~ N~ :t Nn V 
~- - -- -
Q cl Cl7N 0 
~00ONONt-- - 00 tr 0 
- N ~N N N '~-
C=0ne NO 00~0 
- "o ON00 a, mN Ck N N C 
"D C'I Cri Cl 
,'0 - \0 0 O m~ ON - 110 N00 
o~~~~' 4........... m-
_~ ~ 0 0 O C1-4 00 00 00 
~~t0 00'~c~ C ~ ~ - CfN4.10

o oo o oO O o A o 
0 0 0 0 ~ 0 O 0 0 
-e- -0 - be ob b e 2 
8 
Q o o o > o >oo 
Co ~ ~ t -. o m... Q~ >C0 Utz ~ ~>.0 >~o 
-o o -= M- abbbob~ h 
(n. 0 .20 n0 V)00 CI)0 P.C to > P 0, 0 P., 00 PC 00 >C 00 C, 0 
- 0 o)0 o 0 o )0 o>0 > 0 o 0o 
- U U Uo' . ~ > 
- =-o == =- =- =- .5 
z8 0 s 0 0 0 a0 DMS ,:a .0 0-:z 20. b a e 
= - = * = .- ~ 0- . -- -o C 
o -- o - o
o C - ~ 2 5 b.  
o o oA w.  
5- -o w -o o.  
o Ue 
u o> C >v) > >ov > 5 > o > o > o > Co > o 
o b 
-C 0 0 0 - -S2 o - 2 oo M 0 0 0 o C.  
[ o v o '0o ') o v o > > o o o o 
o o 0-2 -o -R -o . -o 0-o 
oo 0 o 0 0o 0o >->o >"eo 
o ~ g go tbObobO b $ b b b b 
C U 0 bb. 0 0 00 ' =. wO ' ~ > >0 >0 
C a. g - o 'C o o .00 ) 'O o .e '0 - o 7- o '- o '- o N- oo 
eoa a C- :2 8 oo gg C. zC >e g Co C-  e 0 - -' I.. g e > U 0  Ug 2  iU2$ i . Ug $ igo> 
. > > o > o. 51 o o o:>B > o> > . o > 3o >m o > .o > o 
4 - - - -0 
0)000.0 00. 00o 00.0 000 2 -v; 
_ 
Ts', o o$U 
> o 0o 0 0 0) 00 2 > o >-o = o o > o =-o 
2 .!2 002 00 00 0 0 0 
.- .0o .o .o .0 o. t 0 o - Co Q- Co ' o- o 
.0= bb= .0 0. . ..oCC 
-~ ~, ~ 2 .o 2, . => 
op U o o 0 C u). 0 b C Co. Co 0.0) o0 v)0 '0 I0  = 55 
b o '.2 bo .2 &. b'. b'. 60 ib. 5bfE t O.2 8.2 ib.~.Co UC .CE. C.E.C U-Uo . = .C 1 . . .  
e o a~ oe we r ~ e e F2~ t oe 79. o o :9.  
-- U> mo oo >o >o o >0> >.o >o >.o >0o >00 
N m BZo 
0) 
. U U -9 U'i to=~ 
m c o mno u o u)o L)o > - o > o > m 
-2 -. o -. 2 -. 2 om o 
> 2 >> 
.2 
> 2 22 .0 22 B .> 22 2 .  
>0) 0)0 7 ) 0)o 7/0)0 o n >2>>5 2o > 3o >*o 52 >*23 
0'2 0R .. 0 .. 0. . 0 a0 '0 '0o '0 '0.2 6 t0 C o B 0 Co- 6 C ' C > So z~ o Jo = a =0 72 09 79 
Co~~ Co> >. >C.C >~' >~2 ~ 2 
Co C '0 .0 to0 ~'to 'to~0 to000 '0 
to 00 02 0. to0 UUo ~ 0 ~ ~ ~ 0 
-~~ 0 - C-. gC. =C- g0) U.=. ) U...) 
... 6.  U..g 
.411)~~~~ 0> ) 0) ) ) ) *2 > 2 'o >0 > o > *2o 
4)~b t 0 ' 2 ' 2 ' 2 ' 2*. ' o o000 '0 C 'Zo 0 C 
~~~~ ~~~~ o0 o. C C 40 > ~ C 0  o CC 
Co o*~~ ... 0 0
4. U.C 
-a~ 4 .15 0)0 0)0 -U0 0)0 -U2 u~2 >2o >*oU2 
Ib T, 0w to j - to4- t: o 
~~ .2 '02 '0~2 '0 '20 0o 'C 
- 02 0 ;:02 o2 00 C.o~C- -C 
Uz > ' > C> Co2 > >>. a>C.0 a>M. z >Cz.0 
U~~~~~ ~~ 000 0.500 0. 00 ~ C 
0>0 >)0 >)0 >)0 >)0 0)0 >> > >'2 >'2 > P- > > 
M9 .) w 99 .9D t 9 m. 0 0 0 0 - 0 
Co Co00 0 .. 0 .. 0 .. 0 .. 0 
spq .0aul Slo '0 = .0 ' . 0 0 0

[0267] PET testing results for 12-month MG33PB stored at 40 'C. The results of the preservative 
efficacy tests (PET) are summarized in Table 18 and Table 19. Gel MG33PB stored for 12 months at 
'C meets the required log reductions against all organisms tested as specified by the European 
Pharmacopeia 6.3.  
Table 18 
Inoculation size for each organism applied to test Gels 
Organism Stock (Cfu/ml) Final theoretical 
concentration in each 
formulation (Cfu/ml) 
S. aureus 3.1 x 108  3.1 x 106 
. coli 2.1 x 10' 2.1 x 106 
Ps. aeruginosa 1.3 x 108 1.3 x 106 
C. albicans 1.1 x 107  1.1 x 105 
A.niger 1.5 x 107 1.5 x 105

[0268] Analysis of 12-month with 6-month additional ambient storage and 18-month samples using 
validated analytical method 2. The sample stored for 12 months at 25 'C was stored for an additional 
6 months at ambient temperature and the 18-month samples stored at 25 0C and 40 'C conform to the 
specification criteria for MTZ and preservatives content (Table 20 and Table 21)

[02691 Effect of 75 and 90% w/w preservatives composition on MG33PB. The results for the PET 
test carried out with variants of exemplary gel MG33PB containing reduced quantities of 
preservatives, MG33 (75%) and MG33 (90%) are summarized in Table 22 and Table 23.  
MG33 (70%) and MG33 (90%) conform to the required log reductions against all organisms tested as 
specified by the European Pharmacopeia 6.3.  
Table 22 
Inoculation Size for Each Organism Applied to Test Gels 
Organism Stock (Cfu/ml) Final theoretical 
concentration in each 
formulation (Cfu/ml) 
S. aureus 2.0 x 108  2.0 x 106 
E. coli 3.3 x 108  3.3 x 106 
Ps. aeruginosa 3.8 x 108  3.8 x 106 
C. albicans 1.8 x 108  1.8 x 106 
Aniger 1.5 x 108 1.5 x 106

Example 6: Local Delivery and Skin Penetration Properties of the Exemplary 
Gels 
[02701 The in vitro skin permeation properties of several exemplary high degree mucoadhesive MTZ 
aqueous-based gels were tested in a Franz cell with a full thickness of human abdominoplasty skin 
obtained with informed consent. For the studies, all subcutaneous fat was removed with a scalpel and 
the skin was mounted in-between the donor and receiver compartments.  
[0271] For the experiment, 14C radiolabeled MTZ gels were prepared as described in Example 2 with 
the quantities of ingredients listed in Table 24, below. In Table 24, all quantities are in mg, which the 
exception of 14C-labeled MTZ, which is in l.

r- t ID I 1 1 1 0 o - COO\ - t 
It\0 =l - 0 00 o 
\ 6 C C C0 4 0 
~t\~OO Cl\ C)OOO r 
CLn tn 00 \0 - L 
k- 0 06 C-i 0 M0t 
C) C C>C C 0 
PLO- tn 
'.0 0 O 

[0272] The 14C radiolabelled MTZ (GE Healthcare) had a specific activity of 57 mCi/mmol with a 
radiochemical purity of 99.2%. 14C-labeled MTZ stock solution was prepared by adding 3.5 ml water 
to 37 MBq of 14C-labeled MTZ and vortex mixing until the 14C-labeled MTZ dissolved.  
[02731 As a control, 10 g of a 0.75 wt% 14C-labeled MTZ gel corresponding to FDA approved 
0.75 wt% MTZ gels (such as, for example, METROGEL VAGINAL@) was prepared as follows: 
[02741 Paraben phase: Methyl paraben (8.03 mg), propylparaben (2.05 mg) and propylene glycol 
(303.28 mg) were weighed into a 28 ml glass vial and stirred until dissolved. The vial was then 
equilibrated at 55 'C and water (3.5 g) added while stirring. MTZ (75 mg) was added and stirring 
continued until all the drug had dissolved. 14C-labeled MTZ stock solution (465 tl) was then added 
while stirring.  
[0275] Carbomer phase: Disodium EDTA (5.03 mg) was weighed into a 28 ml glass vial to which 
purified water (5.698 g) was added. A magnetic flea was used to stir the formulation until all the 
disodium EDTA was fully dissolved. Carbomer 974P (200.89 mg) was added and the formulation 
left stirring overnight to allow the polymer to hydrate.  
[0276] Combination: The paraben phase was added to the carbomer phase while stirring. The 
paraben phase was rinsed into the carbomer phase using water (200 mg). The gel was left overnight 
to cool to room temperature.  
[0277] For the experiment, a full thickness human skin was mounted in a Franz cell with a Ph 4 
phosphate buffer (pH 4) as receiver fluid to ensure sink conditions. A finite dose of test gel 
equivalent to 10 mg/cm2 was applied to the membrane and the diffusion of 14C-labeled MTZ 
determined over time.  
[0278] The test gels (7 l) were applied to the surface of the membrane using a positive 
displacement pipette. Due to the large number of gels tested, the study was split into several separate 
experiments. Two skin donors were randomly assigned across all experiments so that each gel was 
tested on both skin donors (n=6 cells per gel).  
[0279] The receptor compartment of the Franz cells was filled with receiver fluid and the cells fixed 
in a water bath maintained at 37 'C. The receptor chamber contents were continuously agitated by 
small magnetic followers. At t = 1, 2, 3, 4, 6, 8 and 24 h, samples of receiver fluid were taken from

the receptor compartment, and replaced with fresh receiver medium and assayed by scintillation 
counting.  
[02801 At the end of the experiment, a mass balance was carried out, analysing donor chamber, 
surface residue, Stratum corneum (SC), remaining epidermis, dermis and receiver chamber. The 
method involved removal of the SC by tape stripping and processing of the remaining epidermal layer 
and dermis using standard procedures. The methods are described briefly below.  
[02811 Unabsorbed formulation: the surface of each Franz cell donor chamber was wiped gently 
with a cotton bud using 5 clockwise and anti-clockwise movements. The procedure was repeated on 
four occasions using alternate wet (previously immersed in receiver fluid) and dry cotton buds. The 
cotton buds were added to scintillation cocktail before analysis. Two tape strips were removed from 
the skin and regarded as the unabsorbed formulation and included in the total surface activity. The 
tape strips were placed into a scintillation vial to which 1 mL of water was added. These were left to 
soak for 72 h to allow the formulation to dissolve and disperse into water. Scintillation cocktail 
(4 mL) was added to the vial prior to analysis by liquid scintillation (LSC). The surface of each Franz 
cell receiver chamber was wiped gently with a cotton bud using five clockwise and anti-clockwise 
movements. This procedure was repeated on two occasions using alternate wet (previously immersed 
in receiver fluid) and dry cotton buds. The cotton buds were added to scintillation cocktail before 
analysis.  
[0282] Stratum corneum (SC): SC was removed by carefully tape stripping the skin ten times using 
Scotch adhesive tape. The first five tape strips were placed together in one scintillation vial and the 
second five together in a second vial. 1 mL of water was added to each vial and these were left to 
soak for 72 h to allow the formulation to dissolve and disperse into the water. Scintillation cocktail 
(4 mL) was added to the vial prior to analysis by LSC.  
[0283] Epidermis: The remaining section of the epidermis (following tape stripping) was carefully 
removed from the dermis with a scalpel. The epidermis was placed into a glass vial containing 2 ml 
of Soluene 350 and incubated at 50 'C for 72 h before analysis by LSC.  
[0284] Dermis: The remaining dermal layer was placed in to a glass vial containing 2 ml of Soluene 
350 and digested by incubation at 50 0C for 72 h before analysis by LSC.

[0285] Results. The amounts of 14C-labeled MTZ recovered from the various skin layers for each 
gel tested are provided in Table 25, below. These are represented graphically in FIG. 3A. The same 
data represented as a percentage of the applied dose are provided in Table 26, below and graphically 
in FIG. 4A.  
[0286] Additional graphical representations are provided in FIGS. 5A and 6A.  
[0287] There was no statistical difference (p > 0.05) between the amount of MTZ detected in the 
donor chamber, receiver chamber, epidermis, and dermis for any of the formulations tested.  
However, significant differences in the amounts detected in the receiver fluid and the Stratum 
corneum were observed with the high dosage MTZ gels as compared to 0.75 wt% Metrogel@. The 
levels of MTZ observed in the receiver fluid following application of Metrogel@ (4.83 ± 0.97 gg) 
were 4-16 higher (2-9 fold when normalized for concentration; p <0.05) than from the new PB 
formulations (min 0.31 ± 0.27 ptg from MG33PB and max 1.17 ± 0.25 ptg from MG36PB), with the 
possible exception of MG37PB (3.62 ± 2.02 jig). However the levels of 14C-labeled MTZ in the 
Stratum corneum following application of the exemplary test gels (min 17.80 ± 3.45 Ig from 
MG36PB and max 33.15 ± 19.86 ptg from MG35PB) were 50-90 fold higher (29-53 fold higher when 
normalized to concentration) than those obtained for Metrogel@ (0.37 : 0.74 pg). This difference 
was reflected in the amount of radio-labeled MTZ recovered unabsorbed from the skin surface were 
the amount of drug recovered from the Metrogel@ formulation (45.03 ± 1.20 jig) was comparable to 
the exemplary test gels (min 55.69 ± 5.42 [tg from MG33PB and max 65.23 ± 3.29 pig from 
MG34PB) despite the difference in initial concentrations.  
[0288] A similar experiment was carried out with exemplary gels containing 1.5 wt% MTZ, yielding 
similar results (provided in FIGS. 3B, 4B, 5B and 6B).  
[0289] Thus, a greater quantity of MTZ is retained in the superficial layers of the skin with the high 
dosage mucoadhesive MTZ aqueous-based gels described herein as compared to conventional 0.75 
wt% MTZ gels, while at the same time yielding lower levels in receiver fluid, corresponding to 
expected lower systemic levels when applied topically to skin.

Example 7: Permeation Studies With Porcine Vaginal Tissue 
[02901 A permeation study with exemplary test gel MG33PB and a 0.75 wt% MTZ control gel 
similar to that described in Example 6 was carried out in a Franz cell using porcine vaginal tissue 
from which excess muscle was removed. MTZ was extracted from tissue using Soluene. In this 
experiment, gels did not include "'C-labeled MTZ. MTZ recovery was measured via HPLC. The 
mean quantities of MTZ recovered from the surface of the vaginal tissue and from within the vaginal 
tissue 24 hr after application of test or control gel are provided in Table 27, below. In the data below, 
n = 5, with one outlier from each of the test and control experiments having been eliminated.  
Table 27 
Mean MTZ Recovery (pg) 
Surface Vaginal Tissue 
(mean + SEM) (mean ± SEM) 
MG33PB 0.175 ± 0.045 9.615 ± 2.825 
0.75 wt% MTZ control 0.000 t 0.000 4.287 ± 0.707 
[0291] The data are also represented graphically in FIG. 7. The cumulative amount of MTZ that 
permeated through the vaginal tissue as a function of time throughout the course of the experiment 
are illustrated in FIG. 8. In FIG. 8, data are represented as the mean (± SEM) amount of MTZ (in [tg) 
that permeated per unit area of vaginal tissue (pg/cm 2). N = 5 for both test and control batches.  
[02921 In this experiment, only about 30% of the total amount of MTZ applied for both the test and 
control gels was recovered.  
[02931 Only approximately 30% of the total quantity of MTZ was recovered from both the test and 
control arms of the experiment.  
Example 8: An Exemplary High Dosage Mucoadhesive Aqueous-Based Gel 
Containing 1.3 wt% MTZ is Surprisingly Effective, and Surprisingly 
More Effective than an FDA-approved 0.75 wt% MTZ Gel When 
Clinically Used to Treat Women Diagnosed With Bacterial 
Vaginosis 
[0294] Introduction. A clinical evaluation of a specific embodiment of a high dosage 
mucoadhesive MTZ aqueous-based gel containing 1.3 wt% MTZ, formulation MG33PB, was carried 
out to assess its safety and efficacy. In the study, MG33PB was evaluated against 0.75 wt%

METROGEL VAGINAL@ ("MGV") and different test groups were used to determine the efficacy of 
treatment after 1, 3, and 5 days.  
[02951 General Methodology. A multicenter, randomized, investigator-blinded, dose-ranging 
efficacy and safety study of MG33PB (QD x 1 day, QD x 3 consecutive days, and QD x 5 
consecutive days) compared with MGV (QD x 5 consecutive days) for the treatment of BV was 
conducted in accordance with the FDA Guidance (draft FDA guidance titled, "Guidance for Industry: 
Bacterial Vaginosis- Developing Antimicrobial Drugs for Treatment," draft dated July, 1998).  
Subjects were evaluated at 3 time points: one Screening/Baseline Visit, one Post-treatment Phone 
Call, and one End of Study [EOS]/Test-of-Cure [TOC] Visit). Subjects participated for up to 30 days.  
The study design is presented schematically in Table 28: 
Table 28 
Screening/Baseline Post treatment Phone Call EOS/TOC Visit 
Day 1 Days 8 to 10 Days 21 to 30 
Visit 1 Phone Call Visit 2 
[0296] Study Population. Participants who met all of the inclusion criteria delineated below were 
permitted to participate in the study. Those who met any one of the exclusion criteria delineated 
below were not permitted to participate in the study.  
Inclusion Criteria 
1. Willing and able to give written informed consent.  
2. Female at least 18 years of age.  
3. In good general health, as confirmed by a medical history at screening visit with no known 
medical conditions that, in the Investigator's opinion, might interfere with study participation.  
4. Willing and able to participate in the study as an outpatient, make required visits to the 
study center, and comply with all study requirements including concomitant medication and other 
treatment restrictions.  
5. For women of childbearing potential, have a negative urine pregnancy test result prior to 
study treatment initiation.

6. Have a clinical diagnosis of BV, defined as having all of the following criteria: 
1. Off-white (milky or gray), thin, homogenous discharge, 
2. The presence of clue cells >20% of the total epithelial cells on microscopic 
examination of the saline wet mount, 
3. pH of vaginal fluid >4.7, and 
4. Positive 10% KOH whiff test.  
7. Agree to abstain from sexual intercourse throughout the first 7 days of the study.  
Following the first 7 days, agree to use a non-lubricated condom when engaging in sexual intercourse.  
8. Are willing to abstain from alcohol ingestion during the treatment period and for 1 day 
afterward.  
9. Agree to refrain from the use of intravaginal products for the duration of the study (e.g., 
douches, feminine deodorant sprays, spermicides, lubricated condoms, tampons, and diaphragms).  
Exclusion Criteria 
1. Are pregnant, lactating, or planning to become pregnant during the study period.  
2. Are menstruating at the time of the diagnosis or anticipate the onset of menses during the 
treatment phase of the study.  
3. Experience a clinically important medical event within 90 days of the visit (e.g., stroke, 
myocardial infarction, etc.).  
4. Have known or suspected other infectious causes of vulvovaginitis (e.g., Candidiasis, 
Trichomonas vaginalis, Chlamydia trachomatis, Neisseria gonorrhoeae, or active Herpes simplex) or 
any other vaginal or vulvar condition that, in the Investigator's opinion, will confound the 
interpretation of clinical response (Chlamydia trachomatis and Neisseria gonorrhoeae test results are 
not available at the time of randomization).

5. Have a Gram stain slide Nugent score of <4 (results are not available at the time of 
randomization but are utilized to determine post-study analysis populations).  
6. Received antifungal or antimicrobial therapy (systemic or intravaginal) within 14 days of 
randomization. Anti-viral therapies (non-intravaginal) are acceptable.  
7. Have taken disulfiram within 14 days of randomization.  
8. Demonstrate a previous hypersensitivity reaction to metronidazole, either orally or 
topically administered, or any form of parabens.  
9. Have a primary or secondary immunodeficiency.  
10. Are being treated or are planning to be treated during the study period for cervical intra 
epithelial neoplasia (CIN) or cervical carcinoma.  
11. Are using anticoagulation therapy with Coumadin (warfarin).  
12. Are using systemic corticosteroids or systemic antibiotics.  
13. Are previously enrolled in this study.  
14. Participate in another clinical trial or have taken an experimental drug or device within 
the last 30 days.  
15. Are unwilling or unable to comply with the requirements of the protocol.  
[0297] Treatment Groups. After all screening/baseline evaluations and assessments were completed, 
subjects were instructed in the proper technique for application of study drug and were randomly 
assigned by an Unblinded Drug Dispensing Coordinator in a 1:1:1:1 ratio to one of the following 
treatments groups: 
* MGV: QD x 5 consecutive days, 
* MG33PB: QD x 1 day, 
e MG33PB: QD x 3 consecutive days, and

* MG33PB: QD x 5 consecutive days.  
[0298] Each subject received 1 kit of study drug. Each kit contained either: 
* Study medication, MG33PB, supplied in one 70-gram tube with the 
appropriate number of applicators, or 
* Comparator medication, MGV, supplied in one 70-gram tube, with five (5) 
applicators.  
[0299] Various subgroup populations were assessed for outcome (discussed in more detail, below).  
The "Intent-to-Treat" (ITT) population included all subject randomized into the study. The "Modified 
Intent-to-Treat" (MITT) population included all subjects randomized who received any study 
medication, had at least 1 post-baseline visit/assessment, had a negative test for Neisseria 
gonorrhoeae and Chlamydia trachomatis, and a Gram stain slide Nugent Score of >4 at Visit 1.  
Subjects with missing primary efficacy data were counted as failures for the primary efficacy 
endpoint and were included in the MITT population. The "Per-Protocol" (PP) population included 
subjects in the MITT population who met the following criteria: 
Satisfy all inclusion and exclusion criteria and have no protocol violations, 
* Start study medication on the day of or within two days after the day of 
randomization, 
* Are compliant with study medication, 
* Have no antimicrobial drug use (other than allowed per protocol) during 
study period (Randomization through the TOC visit), 
e No additional intravaginal products during the duration of the study, and 
* Have the TOC Gram's stain Nugent score result obtained between days 20 
and 31, relative to the first day of treatment.  
* A subject whose end of study visit was prior to day 21 was included in the 
PP population if data indicated that the subject was a clinical failure for 
bacterial vaginosis without another specified cause (i.e., trichomonas, 
chlamydia, gonorrhea).  
[0300] The "Safety" population included all randomized subjects who applied any amount of study 
medication.

[03011 Blinding. Since the study medication and the comparator were dosed using different 
treatment regimens, an Investigator-blinded study design was utilized. Treatment assignment was 
concealed from Investigators and study coordinators, and an independent drug dispensing coordinator 
at each site performed treatment assignment.and dispensing.  
[03021 Restricted Medications/Treatments. The following medications, preparations, and treatments 
that could potentially affect the study results were prohibited during the study: 
1. Alcohol ingestion during the treatment period and for 1 day afterward.  
2. Disulfiram during the treatment period and for 1 day afterward.  
3. Intravaginal products for the duration of the study (e.g., douches, feminine deodorant 
sprays, spermicides, lubricated condoms, tampons, and diaphragms).  
4. Systemic or intravaginal antimicrobial therapies for the duration of the study, with the 
exception of oral antifungal therapy (e.g., oral fluconazole) to treat intercurrent conditions (e.g., 
Candidiasis). Anti-viral therapies (non-intravaginal) were acceptable.  
5. Treatment for CIN or cervical carcinoma.  
6. Coumadin or warfarin.  
7. Systemic corticosteroids.  
[03031 Efficacy and Safety Variables. Efficacy analyses were conducted on both the PP and MITT 
populations.  
[03041 The primary efficacy variable was assessed at Visit 2 (EOS/TOC) and is evidence of a 
therapeutic cure. A subject considered to be therapeutically cured must have achieved both clinical 
cure and bacteriological cure at EOS/TOC.  
[03051 Clinical cure was defined as resolution of the clinical findings from the Baseline Visit and 
was further defined as: 
1. absence of an off-white (milky or gray), thin, homogeneous discharge;

2. negative 10% KOH whiff test; 
3. absence of clue cells in saline wet mount; and 
4. vaginal fluid pH of <4.7 
[03061 In addition, the subject must not have received any antimicrobial drugs (other than allowed 
per protocol) during the study period and the Investigator must have answered "no" at EOS to the 
question "In your opinion, does the patient require additional treatment for BV infection at this time?" 
[03071 Bacteriological cure was defined as a Nugent score of <4.  
[03081 The key secondary efficacy variables for this study were: 
* Proportion of subjects with clinical cure at the TOC/EOS visit.  
Proportion of subjects with bacteriological cure at TOC/EOS visit.  
e Time to resolution of symptoms (abnormal discharge and odor), defined as 
the time interval (in days) from randomization to the day indicating 
resolution of symptoms in the subject's diary.  
Pelvic exam results including itching, irritation, and inflammation.  
* Subject questionnaire and diary data.  
[03091 Subjects who were classified as clinical failures at an unscheduled interim visit had their 
clinical and bacteriological results and treatment assessments carried forward to the EOS/TOC Visit.  
[03101 Safety analyses were conducted on the Safety population and included -an evaluation of 
vaginosis history and prior treatment, pelvic examination, concomitant medication monitoring, and 
AE/SAE monitoring.  
[0311] Statistical Methods and Analyses.  
[0312] Study Populations for Analyses. The various study populations are defined above. The ITT 
population was used to summarize subject disposition, demographic and baseline characteristics, 
medical history, and prior/concomitant medications. The MITT population was used for supportive

efficacy analyses. The PP population was used for the primary analyses. The Safety population was 
used for study drug exposure and all safety analyses. Subjects were analyzed as treated.  
[0313] Statistical Analysis for Primary and Secondary Endpoints. For proportion variables, data 
were summarized by treatment group along with exact 95% confidence intervals (CIs). Subjects who 
received other antimicrobial drugs, i.e., other than those allowed per protocol, during the study (i.e., 
any time from the date of screening/randomization to the date of the last visit) were counted as 
failures.  
[0314] The Kaplan-Meier survival curve for time to resolution of symptoms was plotted for all 
treatment groups.  
[03151 No formal statistical testing was performed to compare treatment groups. Final selection of 
the treatment regimen was based on cure rates, consistency of results, safety, and convenience 
information.  
[03161 Safety Analyses. Safety data was comprised of the assessment (number and %) of all 
treatment-emergent adverse events (TEAEs), any serious adverse events (AEs), treatment related 
TEAEs, severe TEAEs, and AEs leading to study discontinuation for each treatment group.  
[03171 Investigators chose amongst the following terms to describe the severity of an AE: Mild, 
Moderate, or Severe. The relationship of each AE to the study drug was evaluated by the Investigator 
as: Not Related, Probably Not Related, Probably Related, or Related. Note: Treatment-related AEs 
include those that are categorized as Probably Related or Related.  
[03181 Treatment-emergent adverse events (TEAEs) were defined as those AEs that either have an 
onset time on or after the start of study drug and no more than 30 days after the last dose of study 
drug, or that were ongoing at the time of study drug initiation and increased in severity or became 
closer in relationship to study drug during treatment or during the 30 day period after the last dose of 
study drug.  
[03191 TEAEs were summarized by the overall incidence of at least one event, incidence by system 
organ class (SOC), and incidence by SOC and preferred term. TEAEs were also summarized by 
severity and by relationship to study product. Also, the following treatment- emergent AEs were

summarized below: Serious TEAEs, treatment-related TEAEs, severe TEAEs and TEAEs leading to 
study discontinuation.  
[03201 Results of Clinical Evaluation of Safety and Efficacy.  
[03211 Disposition of Subjects. Disposition for the study subjects is displayed in Table 29, below.  
A total of 255 subjects were randomly assigned to the four study treatments and all but one subject (in 
the MGV group) was dosed and included in the Safety population. 234 subjects (91.8%) completed 
the study. Among the 21 (8.2%) subjects who discontinued early, 9 (3.5%) were lost to follow-up, 
(2.0%) had a positive Neisseria gonorrhoeae and/or Chlamydia trachomatis screening test result.  
[03221 There were 255 (100.0%) subjects in the ITT population, 228 (89.4%) subjects in the MITT 
population, and 189 (74.1%) subjects in the PP population. Twenty-seven (10.6%) subjects were 
excluded from the MITT population; the majority 23 (90.0%) because of their baseline Nugent 
scores. For the 66 (25.9%) subjects excluded from the PP population, the most common reason, 
occurring in 30 (11.8%) subjects, was because a Nugent score had not been performed within 20 to 31 
days from the first dose of study medication. A summary of subject populations is provided in 
Table 30, below.  
[03231 Demographics. At baseline, the mean age of subjects enrolled into the study was 35.1 
(±9.93) years. Subjects were evenly divided between groups <35 years (51.4%) and >35 years 
(48.6%) and were balanced by age range across treatment groups. A summary of demographics is 
provided in Table 31, below.

in , CD, CD C: C C a 
Lr? - -
=Cu =,-'1-, 11 -,
_= g(3- C 
n - CDol 0C 
-o ; cd 
~ 0C7 
V) Z co0 
! C)u 00*

S 00 
C; 0 ; 0C'i 0 ~ , 
CN N 
N00 0.  
6 "c~ oo6cl r'- . \ - ro 0 
C) D ~ CN 
-.  
'-5'- '-5'
6 .00 q 
ci 006~ 
In C 00 t C -4 ON C- ) 110, C 
C* - - a 
CIS 
(.t -o (- C 
*cC 0C PLO 
-/) P--4 4

[03241 Bacterial Vaginosis History and Prior Bacterial Vaginosis Treatment. Bacterial vaginosis 
(BV) history and prior treatment for BV are summarized in Table 32, below, for the ITT population.  
Table 32 
Bacterial Vaginosis History and Prior Bacterial Vaginosis Treatment: Intent-to-Treat Population 
MGV MG33PB MG33PB M(G5 sO33PB 
(QD x 5 Days) (QD x 1 Da (QD x 3 Days) (QD x 5 Days) Overall 
Duration of current BV episode at baseline, n (%) 
< 3 weeks 23(34.8) 21(32.3) 22(36.7) 20(31.3) 86(33.7) 
> 3 wks and < 3 mos 25 (37.9) 28 (43.1) 29 (48.3) 27 (42.2) 109 (42.7) 
> 3 mos 18 (27.3) 16 (24.6) 9 (15.0) 17 (26.6) 60 (23.5) 
Duration of current BV episode at baseline, n (%) 
N 66 65 60 64 255 
Mean - - 93.7 150.1 151.6 
(SD) 231.5 (990.20) 125.6 (288.63) (244.45) (459.59) (583.78) 
Median 40.0 41.0 30.5 36.0 36.0 
Min, Max 1,7924 1,2102 2, 1713 1,3534 1,7924 
Had previous episode(s) of BV, n (%) 
Yes 23(34.8) 27(41.5) 25 (41.7) 20 (31.3) 95(37.3) 
No 43 (65.2) 38 (58.5) 35 (58.3) 44 (68.8) 160 (62.7) 
Abbreviations: max = maximum; min = minimum; SD = standard deviation.  
[03251 Overall, 95 (37.3%) subjects reported previous episodes of BV; the mean duration of the 
current BV episode was 151.6 days. The treatment groups were similar with respect to bacterial 
vaginosis history and baseline characteristics.  
[03261 Efficacy Results. Summary of Cure Rates. Summaries of the cure rates (primary endpoint 
Therapeutic Cure Rate and secondary endpoints Clinical and Bacteriologic Cure rates) in the PP 
population and the MITT populations are presented in Table 33, below.

Table 33 
Summary of Cure Rates: Per-Protocol Population 
Number of total subjects (% of total subjects) 
MGV MG33PB MG33PB MG33PB 
(QD x 5 Days) (QD x 1 Day) (QD x 3 Days) (QD x 5 Days) 
Therapeutic cure 
Cured, n (%) 10 (20.4) 13 (30.2) 12 (25.0) 16 (32.7) 
Failed, n (%) 39 (79.6) 30 (69.8) 36 (75.0) 33 (67.3) 
Clinical cure 
Cured, n (%) 14 (28.6) 16 (37.2) 17 (35.4) 22 (44.9) 
Failed, n (%) 35 (71.4) 27 (62.8) 31(64.6) 27 (55.1) 
Bacteriological cure 
Cured, n (%) 15 (30.6) 13 (30.2) 17 (35.4) 23 (46.9) 
Failed, n (%) 34 (69.4) 30 (69.8) 31(64.6) 26 (53.1) 
[0327] As shown in Table 34, below, the results for the MITT population are similar to the PP 
population.  
Table 34 
Summary of Cure Rates: Modified Intent-to-Treat Population 
Number of total subjects (% of total subjects) 
MGV MG33PB MG33PB MG33PB 
(QD x 5 Days) (QD x 1 Day) (QD x 3 Days) (QD x 5 Days) 
Therapeutic cure 
Cured, n (%) 12 (20.3) 15 (25.4) 12 (22.2) 17 (30.4) 
Failed, n (%) 47 (79.7) 44 (74.6) 42 (77.8) 39 (69.6) 
Clinical cure 
Cured, n(%) 17(28.8) 18(30.5) 17(31.5) 23(41.1) 
Failed, n (%) 42 (71.2) 41(69.5) 37 (68.5) 33 (58.9) 
Bacteriological cure 
Cured, n (%) 18 (30.5) 18 (30.5) 18 (33.3) 26 (46.4) 
Failed, n (%) 41(69.5) 41(69.5) 36 (66.7) 30 (53.6)

[03281 Summary of Absent or Present by Each Therapeutic Cure Criteria at the End of Study/Test of 
Cure Visit. The results for absent or present at the EOS/TOC Visit for each of the 4 established 
therapeutic cure criteria are presented for the PP population in Table 35. Results are similar in the 
MITT population.  
Table 35 
Results for Therapeutic Cure Criteria at Test of Cure/End of Study: 
Per-Protocol Population 
Number of total subjects (% of total subjects) 
MGV MG33PB MG33PB MG33PB 
(QD x 5 Days) (QD x 1 Day) (QD x 3 Days) (QD x 5 Days) 
Vaginal discharge 
Absent 22 (44.9) 24 (55.8) 23 (47.9) 38 (77.6) 
Present 27(55.1) 19(44.2) 25 (52.1) 11(22.4) 
KOH whiff test 
Absent 26 (53.1) 23 (53.5) 33 (68.8) 39 (79.6) 
Present 23 (46.9) 20 (46.5) 15 (31.3) 10 (20.4) 
Clue cells (% of vaginal epithelial cells) 
< 20% 27(55.1) 23 (53.5) 28(58.3) 40(81.6) 
> 20% 22(44.9) 20(46.5) 20(41.7) 9(18.4) 
Vaginal pH 
< 4.7 19(38.8) 18(41.9) 24(50.0) 28(57.1) 
> 4.7 30(61.2) 25(58.1) 24(50.0) 21(42.9) 
Investigator questionnaire: Did the subject use other antimicrobial drugs (other than allowed per 
protocol) during the study period (systemic or intravaginal)? 
Yes 0 0 1 0 0 0 
No 49 (100.0) 1 43 (100.0) 48 (100.0) 49(100.0) 
Investigator questionnaire: In the Investigator's opinion, does the subject require additional 
treatment for bacterial vaginosis at this time? 
Yes 24 (49.0) 20 (46.5) 18 (37.5) 9(18.4) 
No 25 (51.0) 23(53.5) 30 (62.5) j 40 (81.6) 
Gram stain for Nugent Scoring 
to 3: BV negative 15(30.6) 13(30.2) 17(35.4) 23(46.9) 
4 to 10: BV positive 34 (69.4) 30 (69.8) 31(64.6) 26 (53.1) 
[0329] Time to Resolution of Symptoms. In the PP population, the median time to resolution of both 
abnormal discharge and fishy odor and the median time to resolution of fishy odor alone are shorter in 
all 3 metronidazole 1.3% treatment groups compared to MGV 0.75% group (median times were 5

days versus 6 and 2 days versus 3, respectfully); the median time to resolution of abnormal discharge 
is equal across all treatments groups (median time is 3 days). A summary of time to resolution of 
symptom(s) is provided in Table 36 below.  
Table 36 
Time to Resolution of Symptoms 
Number of total subjects (% of total subjects) 
MGV MG33PB I MG33PB MG33PB 
(QD x 5 Days) (QD x 1 Day)I (QD x 3 Days) (QD x 5 Days) 
Time to resolution of symptoms (abnormal discharge and fishy odor) 
Subject resolved, n (%) 26 (53.1) 25 (58.1) 29 (60.4) 28(57.1) 
Median days (95% CI)a 6 (4,-) 5(3,-) 5 (3,-) 5(4,-) 
Time to resolution of abnormal discharge 
Subjects resolved, n (%) 43 (87.8) 39 (90.7) 45 (93.8) 42 (85.7) 
Median days (95% CI)a 3(3,5) 3(2,3) 3(2,3) 3(2,5) 
Time to resolution of fishy odor 
Subjects resolved, n (%) 39 (79.6) 33 (76.7) 39 (81.3) 42 (85.7) 
Median days (95% CI) [ 3(2,3) 2(2,3) 2(2,3) 2(2,3) 
a Product-limit (Kaplan-Meier) method estimates; 95% CI calculation is based on the Greenwood 
method 
[0330] Summary of Therapeutic Cure Rates by Subgroups. Therapeutic cure rates in the PP 
population are presented by subgroups (age group, race, ethnicity, duration of current BV episode at 
baseline, and previous episode of BV) in Table 37 below.

Table 37 
Summary of Therapeutic Cure Rate by Age Group, Race, and Ethnicity: 
Per-Protocol Population 
Number of total subjects (% of total subjects) 
MGV MG33PB MG33PB MG33PB 
(QD x 5 Days) (QD x 1 Day) (QD x 3 Days) (QD x 5 Days) 
Age group 
< 35 Years Old 4/24(16.7) 8/26(30.8) 4/29(13.8) 9/21 (42.9) 
> 35 Years Old 6/25(24.0) 5/17(29.4) 8/19(42.1) 7/28(25.0) 
Race 
White 7 / 23 (30.4) 10 / 23 (43.5) 5 / 23 (21.7) 5 / 20(25.0) 
Black/African American 3/26(11.5) 3 / 20(15.0) 7 / 25(28.0) 11 / 29 (37.9) 
Ethnicity 
Hispanic/Latino 1 / 8(12.5) 3 / 5 (60.0) 2 / 8 (25.0) 5 / 11(45.5) 
Non Hispanic/Latino 9 / 41(22.0) 10 / 38 (26.3) 10 / 40 (25.0) 11 / 38 (28.9) 
Duration of current BV episode at baseline 
53 weeks 2 / 16 (12.5) 6 / 14 (42.9) 3 / 15 (20.0) 7 / 13 (53.8) 
>3 weeks and 53 months 5 / 19 (26.3) 3 / 18 (16.7) 8 / 25 (32.0) 5 / 22 (22.7) 
>3 months 3/14(21.4) 4/11 (36.4) 1/8(12.5) 4/14(28.6) 
Previous episode(s) of BV 
Yes 5/18(27.8) 6/21(28.6) 3/19(15.8) ] 6/16(37.5) 
No 5/31(16.1) 7/22(31.8) 9/29(31.0) 10 / 33 (30.3) 
[03311 No significant trends in achievement of therapeutic cure were evident from the analyses by 
subgroup.  
[03321 Subject Questionnaire Results. At the end of study, all subjects were asked to complete a 
questionnaire. The following questions specifically asked of subjects to provide their feedback on use 
of the study drug: 
* How easy was the study drug to apply? 
* How convenient was the length of treatment with study drug? 
* How satisfied were you with the treatment you received? 
* If you had BV symptoms in the future, would you prefer to be treated with 
the current study drug or would you prefer another treatment? 
[0333] A summary of the results is provided in Table 38 below.

Table 38 
Subject End-of-Study Questionnaire Results: Per-Protocol Population 
Number of total subjects (% of total subjects) 
MGV MG33PB MG33PB MG33PB 
Question (QD x 5 Days) (QD x 1 Day) (QD x 3 Days) (QD x 5 Days) 
How easy was the study drug to apply? 
Somewhat easy 0 1(2.3) 1(2.1) 1(2.0) 
Easy 15 (30.6) 4(9.3) 9 (18.8) 12 (24.5) 
Very Easy 33 (67.3) 38 (88.4) 34 (70.8) 33 (67.3) 
Missing 1(2.0) 0 4 (8.3) 3 (6.1) 
How convenient was the length of treatment with study drug? 
Not convenient 1 (2.0) 0 0 1 (2.0) 
Somewhat convenient 8 (16.3) 3 (7.0) 5 (10.4) 7 (14.3) 
Convenient 22(44.9) 5(11.6) 17(35.4) 22(44.9) 
Very Convenient 17 (34.7) 35 (81.4) 22 (45.8) 16 (32.7) 
Missing .1 (2.0) 0 4 (8.3) 3 (6.1) 
How satisfied were you with the treatment you received? 
Not satisfied 3 (6.1) 3 (7.0) 2 (4.2) 0 
Somewhat satisfied 8(16.3) 5(11.6) 4(8.3) 3(6.1) 
Satisfied 15 (30.6) 8 (18.6) 13 (27.1) 15 (30.6) 
Very Satisfied 22 (44.9) 27 (62.8) 25 (52.1) 28 (57.1) 
Missing 1(2.0) 0 4 (8.3) 3 (6.1) 
If you had Bacterial Vaginosis symptoms in the future, would you prefer to be treatment with this 
study drug or would you prefer another treatment? 
Prefer current study drug 24 (49.0) 28 (65.1) 26 (54.2) 36 (73.5) 
Prefer another treatment 8 (16.3) 6 (14.0) 8 (16.7) 4 (8.2) 
No preference 16 (32.7) 9 (20.9) 10 (20.8) 6 (12.2) 
Missing 1(2.0) 0 4 (8.3) 3 (6.1) 
[03341 Among the 4 treatment groups, the highest proportion of subjects rating the treatment as 
"very easy to apply", "very convenient" (for the length of treatment) and "very satisfied" was in the 
MG33PB 1-day group (data not shown).  
[0335] Safety Results. Drug Exposure. Subjects in this 30-day study received either MGV QD x 5 
consecutive days; MG33PB QD x 1 day; MG33PB QD x 3 consecutive days; or MG33PB QD x 5 
consecutive days. A summary of mean days of study drug exposure for the safety population is 
provided in Table 39 below.

Table 39 
Mean Days of Study Drug Exposure: Safety Population 
Number of total subjects (% of total subjects) 
MGV MG33PB MG33PB MG33PB 
(QD x 5 Days) (QD x 1 Day) (QD x 3 Days) (QD x 5 Days) Overall 
Mean (SD) 4.9 (0.53) 1.1 (1.03) 3.0 (0.00) 5.1 (0.76) 3.6 (1.76) 
[03361 The majority of subjects in all treatment groups reported no or minimal leakage of study 
product.  
[03371 Summary of Adverse Events. Overall, 92 (36.2%) subjects reported adverse events (AEs).  
All adverse events were treatment emergent (TEAEs). Twenty-nine (11.4%) subjects across the four 
treatment groups had TEAEs which are assessed by the Investigator as related to study drug. A 
summary of AEs is provided in Table 40 below.  
Treatment-Emergent Adverse Effects. The most frequently reported system-organ classes (SOCs) 
with TEAEs overall were Infections and Infestations (47 [18.5%] subjects), Nervous System 
Disorders (32 [12.6%] subjects), and Reproductive System and Breast Disorders (27 [10.6%] 
subjects). A summary of all TEAES by system-organ class (SOC) is provided in Table 41 below.

N ON 
~N0 000 
M -- o 
Q00 
00 0 0 0 
Q (1) C:)
$..0 .0 
OsQ 0 z" C 
CIo/ o )C)c o V

[0338] The most frequently reported TEAEs with an incidence >2.0% of subjects overall by 
preferred term, regardless of relationship to study medication was vulvovaginal candidiasis 
(25 [9.8%] subjects) and headache (21 [8.3%] subjects). A summary of all TEAEs, regardless of 
relationship to study medication, by preferred term and those reported in >2.0% of subjects overall in 
decreasing order is provided in Table 42 below.  
[0339] The most frequently reported of these TEAEs considered probably related or was related to 
study drug are vulvovaginal candidiasis in the SOC category Infections and Infestations and 
vulvovaginal pruritus and burning sensation in the Reproductive System and Breast Disorders SOC.  
A summary of TEAEs by SOC, preferred term, and relationship to study drug with an incidence of at 
least 6.0% in Overall is provided in Table 43 below.

[0340] The majority of the adverse events were of mild or moderate intensity. A total of five 
subjects reported six severe events adverse events including: hypoglycemia, dizziness, abdominal 
pain, tooth abscess, vulval edema and vaginal burning sensation. One subject (#2904, 1.3% for 1 
day) reported two severe events that were considered related to study product; vaginal burning 
sensation and vulval edema beginning on day 3 of the study. These events occurred concurrently 
with vulvovaginal pruritus, headache, back pain, and vulvovaginal candidiasis. No difference 
between treatment groups in the incidence of severe AEs was observed.  
[03411 Serious Adverse Events. There was one SAE during this study, hypoglycemia in 1 (1.5%) 
subject in the MG33PB QD x 1 day treatment group.  
[0342] Summary. In this Example, the efficacy and safety of a 1.3% vaginal gel for bacterial 
vaginosis (test gel MG33PB) was explored. It was found that the MG33PB once per day for a total of 
1, 3 or 5 days yielded rates of therapeutic cure similar to, or numerically better than, the marketed 
MGV 0.75% vaginal gel (MGV) applied once per day for a total of 5 days (Tables 33-36). No trends 
in efficacy were observed from analysis of the subgroups analyzed (Table 37). The highest 
proportion of subjects rating the treatment as "very easy to apply", "very convenient for the length of 
treatment" and "very satisfied" was in the MG33PB 1-day group (Table 38). The majority of adverse 
events were found to be mild and moderate in intensity (Tables 40-43). Surprisingly, it was 
discovered that a 5 day treatment regimen with MG33PB resulted in no vulvovaginal candidiasis 
being observed post treatment (Table 42).  
Example 9: Antimicrobial Efficacy in an In Vitro Skin Infection Model 
[0343] The antimicrobial efficacy of several exemplary high dosage MTZ gels against Gardnerella 
vaginalis was demonstrated in an in vitro experiment. In the experiment, ATP was recovered from 
infected skin treated with test gels and quantitated. The lower the amount of ATP recovered, the 
more effective the gel against the infection.  
[0344] Two studies were carried out. A pilot study and a full scale study. The general method for 
the pilot study was as follows: 
* .Fresh epidermal membrane was prepared according to a standard protocol and stored 
frozen at -20 'C until required.

* The membrane was cut into 3 mm X 3 mm segments, heat treated at 60 'C for 15 min 
(previous experiments have demonstrated this to be the optimum time of heating, to 
reduce background interference from epidermal membrane, data not presented) and 
infected using 10 ptL of Gardnerella vaginalis (approx 5 x 107 cfu) cell suspensions.  
Viable counts were performed to obtain the number of cell forming units after the 
preparation of the cell suspensions.  
* ChubTur* cells were set up, 3 mL of Ringers was added to the cells to ensure a 
humidity controlled environment.  
* After 24 h incubation at 35 'C, 10 stL of test gel was applied onto the epidermal 
membrane surface.  
* Following incubation of the inoculated epidermal membrane, dosing was carried out 
by applying 2 ptL of test gel to the epidermal membrane samples (n = 3 for each gel 
and time point upon initiation; multiple time points are not measured from the same 
sample.  
* Following dosing, the samples were analyzed for the presence of ATP from viable 
organism after 4, 8 and 24 h.  
* Positive and negative controls were included. The negative controls comprised 
epidermal membrane samples with no organism or formulation added at t = 0, and the 
positive controls comprised epidermal membrane samples with organism only (no 
formulations) added at t = 0.  
[0345] For the full scale study, the following changes were made to the protocol: 
* The initial infection of the epidermal membrane and the anaerobic incubation time 
before dosing was reduced to 30 min.  
* The exposure time to gels was reduced to 2 h to minimize the natural decrease in 
organism viability with time.  
* Efficacy of the gels was tested 2 h after application of gel onto epidermal membrane 
samples infected with G. vaginalis by removing the ChubTur* cells from incubation 
and performing ATP assay.  
[0346] Results. Pilot Study. FIG. 9 shows the variation in ATP release (for a 10 application dose) 
from Gardnerella vaginalis infected EP samples, on application of exemplary active gel MG32PB 
(n = 3, upon initiation) and its comparison with un-treated infected EP samples. Corresponding 
placebos, MG32PB-P, and controls were tested at n =2. The lower the amount of ATP recovered, the 
higher the efficacy of the test gel against the test organism.

[0347] From the data presented in FIG. 10, it is observed that the positive control (infected, un
treated epidermal membrane) as expected, gives a high recovery of ATP while a lower amount of 
background interference is observed for the negative controls (un-infected, un-treated epidermal 
membrane). The dosing time with formulation also shows an effect on the ATP recovery. It is seen 
that following 24 hour dosing the levels of ATP reduces close to the background ATP (negative 
control) level. This phenomenon, although to a lesser extent, is also observed for the 8 hour time 
point. From this pilot study, it was determined that the initial incubation time (4, 8 and 24 hour) 
should be reduced in order to decrease the effect of natural cell death over time. The dosing time was 
reduced to 2 hour for the full scale study.  
[0348] Results. Full Scale Study. FIG. 11 shows the variation in ATP release from Gardnerella 
vaginalis (ATCC 14018) infected epidermal membrane samples, on application of the test gels, (n=6, 
upon initiation for active test gels and n = 3 for placebos) and their comparison with the commercial 
comparator, Metrogel*. Positive controls (Gardnerella vaginalis infected epidermal membrane 
samples without any treatment) and negative controls (epidermal membrane samples with no 
infection or treatment) were also included.  
[0349] The data presented in FIG. 11 show that a reduction in ATP recovery is observed for the 
infected skin samples, treated with the active test gels when compared to the recovery of ATP from 
infected skin samples treated with the corresponding placebo gels. Formulation MG32PB showed a 
significant difference in terms of efficacy, with respect to the ATP levels recovered (data not shown) 
between the active and placebo. There was a significant difference (p<0.05) showing a larger 
reduction in ATP recovery for the active of MG32PB compared to the infected control, indicating 
good efficacy of the formulation.  
[03501 Infected skin samples treated with exemplary test gel MG33PB showed significantly lower 
(p<0.05) ATP recovery for both the active and placebo compared to the infected control. The high 
efficacy of formulation MG33PB, placebo was surprising considering the main difference between 
this formulation and the other formulations is Polycarbophil AA-1, a bioadhesive polymer, an 
excipient, only present in MG33PB formulation.  
[0351] Formulation MG35PB had little or no effect in reducing organism viability for the active 
when compared to the infected samples not previously treated with any formulations.

[0352] Formulations MG32PB-A, MG33PB-A and MG33PB-P, all indicated a comparable (P<0.05) 
level of activity against Gardnerella vaginalis on human epidermal membrane. However, Metrogel* 
was significantly (p<0.0 5) more efficacious when compared to MG32PB-P, MG35PB-A and 
MG35PB-P.  
[0353] Summary. MG33PB-A and MG32PB-A were observed to have higher efficacy than other 
formulations. However, it was also surprisingly discovered that MG33PB-P (having no 
metronidazole) was just as effective as the MG33PB (1.3% metronidazole) against Gardnerella 
vaginalis.  
Example 10: In Vitro Evaluation of Novel Metronidazole Formulations for 
Antimicrobial Efficacy Using a Disc Diffusion Zone of Inhibition 
Assay 
[0354] Introduction. A study was performed to determine the minimal amount of benzyl alcohol 
necessary to inhibit microbial growth. In the study, antimicrobial efficacy of three placebo and one 
active high dosage MTZ gels against Gardnerella vaginalis were tested a disc diffusion zone of 
inhibition assay.  
[0355] The gels tested are provided in Table 44, below: 
Table 44 
Theoretical Compositions of Formulations for In Vitro Antimicrobial Efficacy 
Composition (% w/w) 
MG33PGP MG33PGP MG33PGP MG33PG 
0%BA 1%BA 2%BA 2%BA 
Metronidazole 0.00 0.00 0.00 1.30 
Deionized Water 57.90 56.90 55.90 54.60 
Polycarbophil AA-1 2.00 2.00 2.00 2.00 
Methyl paraben 0.08 0.08 0.08 0.08 
Propyl paraben 0.02 0.02 0.02 0.02 
Benzyl alcohol 0.00 1.00 2.00 2.00 
Propylene glycol 15.00 15.00 15.00 15.00 
Polyethylene glycol 400 25.00 25.00 25.00 25.00 
Total 100.00 100.00 100.00 100.00 
"P" designates a placebo gel; "BA" is benzyl alcohol

[03561 For the assay, 3 ml of a Gardnerella vaginalis suspension adjusted to approximately 
1 x 109 cfu/ml was prepared. A 100 gl aliquot of the suspension was pipetted onto the surface of the 
pre-poured Columbia blood agar (CBA) plates and the suspension spread evenly over the surface of 
the agar with a sterile spreader. The agar plate was then left to dry under the laminar flow cabinet.  
The zone of inhibition assay was then carried out by applying 20 pl of the test gel to the surface of a 
1/4 antibiotic assay disc (n = 6 for each gel, note; the disc does not contain any antibiotics) and 
allowed to air dry for a period of 1 min under the laminar flow cabinet. The disc was then inverted 
and placed onto the surface of the plate pre-seeded with Gardnerella vaginalis and incubated in 
anaerobic jars at 35 'C for 48 h. Conditions were maintained as anaerobic by the use of 
AnaeroGenTM gas packs. Following incubation, the zone of inhibition for all of the formulations was 
measured with calipers.  
[03571 Results. The results, shown in FIG. 12, indicate MG33PB is efficacious against Gardnerella 
vaginalis where zones of inhibition are observed on CBA plates (data not shown). No activity was 
seen with any of the placebos MG33PB placebo (0%, 1% and 2% BA) as indicated by no zones of 
inhibition observed on the plates compared to the active formulation.  
[0358] Summary. MG33PB is efficacious against Gardnerella vaginalis as compared to placebo 
gels that do not contain MTZ.  
[0359] The disclosures of the patents, patent documents, articles, abstracts and other publications 
cited herein are incorporated herein by reference in their entireties as if each were individually 
incorporated. In case of conflict, the present specification, including definitions, shall control.  
Various modifications and alterations to this invention will become apparent to those skilled in the art 
without departing from the scope and spirit of this invention. Illustrative embodiments and examples 
are provided as examples only and are not intended to limit the scope of the present invention. The 
scope of the invention is limited only by the claims set forth as follows.  
[03601 All publications, patents, patent applications and other documents cited in this application are 
hereby incorporated by reference in their entireties for all purposes to the same extent as if each 
individual publication, patent, patent application or other document were individually indicated to be 
incorporated by reference for all purposes.

[0361] While various specific embodiments have been illustrated and described, it 
will be appreciated that various changes can be made without departing from the spirit 
and scope of the invention(s).  
[0362] Throughout this specification, unless the context requires otherwise, the 
word "comprise", or variations such as "comprises" or "comprising", will be understood 
to imply the inclusion of a stated step or element or integer or group of steps or 
elements or integers but not the exclusion of any other step or element or integer or 
group of elements or integers.  
[0363] Any discussion of documents, acts, materials, devices, articles or the like 
which has been included in the present specification is not to be taken as an admission 
that any or all of these matters form part of the prior art base or were common general 
knowledge in the field relevant to the present disclosure as it existed before the priority 
date of each of the appended claims.

CLAIMS: 
1. A single dose metronidazole gel composition comprising: 
i. 60-70 mg of metronidazole; 
ii. about 30% to about 60% of water by weight of the single dose 
metronidazole gel composition; 
iii. at least one mucoadhesive gelling polymer; and 
iv. about 30% to about 60% of a ternary solvent system by weight of the 
single dose metronidazole gel composition, the ternary solvent system 
comprising: 
1) one or more lower aromatic alcohols; 
2) one or more lower alkylene diols; and 
3) one or more polyoxyalkylenes.  
2. The composition of claim 1 wherein: 
the one or more lower aromatic alcohols is selected from the group consisting of 
benzyl alcohol, 2-methylbenzyl alcohol, phenoxyethanol, and mixtures thereof; 
the one or more lower alkylene diols is selected from the group consisting of ethane
1,2-diol (ethylene glycol), propane-1,2-diol (propylene glycol), and mixtures thereof; 
and 
the one or more lower polyoxyalkylenes is selected from the group consisting of 
polyoxyethylene (polyethylene glycol), polyoxypropylene, (polypropylene glycol) 
and mixtures thereof, and mixtures of the foregoing.  
3. The composition of claim 1 or claim 2 wherein the one or more mucoadhesive gelling 
polymers are selected from the group consisting of hydroxyethylcellulose, a 
carbomer, a polycarbophil, and mixtures thereof.

4. The composition of any one of claims I to 3 wherein the one or more lower aromatic 
alcohols comprises about 1% to about 5% of weight of the ternary solvent system.  
5. The composition of any one of claims I to 4 with a pH from about 3.0 to about 5.0.  
6. The composition of any one of claims I to 5 that exhibits a viscosity of about 200,000 
mPa to about 400,000 mPa at 25'C using a controlled shear rate ramp method, a 
Bohlin CVO 100 rheometer and the rheometer settings of Table 11.  
7. The use of the single dose composition of any one of claims I to 6 for treating a 
subject with bacterial vaginosis by administering the single dose composition 
intravaginally to the subject once a day for one, two or three days.  
8. A method of treating a subject with bacterial vaginosis, the method comprising 
administering a single dose composition of any one of claims 1 to 6 intravaginally 
once a day for one, two or three days.

Sign in to the Lens

Release 5.10.0: Improved patent search performance, saved query alerts, increased user privacy and more!

Improved Search Performance

Upgraded patent search index servers to improve search performance.

Saved Query Alerts.

Improvements to in saved query alerts emails and better formatting of links.

Increased User Privacy.

Removed Google Maps dependency in a Patents Family page.