Study of Antibiotic-induced Vaginal Yeast Infections in Healthy Women

This protocol is a prospective, interventional, randomized, double-blind, placebo controlled
longitudinal study designed to investigate the microbiomic and immunologic perturbations that
lead to vulvovaginal candidiasis (VVC) in women who receive antibiotics. VVC is the most
common fungal infection affecting women. Although asymptomatic vaginal Candida colonization
occurs in ~10-20% of healthy women, ~75% of women will experience at least one episode of
symptomatic VVC during their lifetime. Nonetheless, the local mucosal factors that allow
Candida to convert from a commensal organism to an opportunistic pathogen are not well
defined. Antibiotic use (particularly beta-lactams) is a well-recognized risk factor for the
development of VVC in healthy women, suggesting that alterations in the endogenous vaginal
microbial flora results in deregulation of local mucosal anti-Candida immune responses.
However, which commensal vaginal microbiota are important for protection against Candida
infection, and the mechanism(s) whereby vaginal microbiota influence the local mucosal immune
response against Candida, remain unknown.

To address these questions, healthy women of reproductive age will receive a 10-day course of
amoxicillin (a broad-spectrum, beta-lactam antibiotic) or a placeboand will undergo vaginal
sampling for microbiomic and immunologic analyses before, during and after antibiotic
administration over a 90-day period. The hypothesis of this study is that women who develop
amoxicillin-associated VVC will have a characteristic microbiomic profile (as compared to
women with absent or asymptomatic Candida colonization) with associated impairment in local
mucosal anti-Candida immune responses. The aim of this study is to elucidate the vaginal
microbiomic and immunologic perturbations that allow Candida to transition from commensal to
pathogen in the context of antibiotic administration. A better understanding of the role of
specific microbiota and mucosal immune factors in averting Candida infection may lead to the
design of targeted preventive and/or therapeutic interventions against VVC.

- INCLUSION CRITERIA:

Females 18-40 years of age must meet the following criteria to be eligible for
participation in this study:

- Willing and able to comply with the procedures of the protocol

- Able to provide informed consent

- Able to swallow capsules

- Have a history of regular (approximately 21-35 day) menstrual cycles prior to
initiation of hormonal contraception

- On oral contraceptives for at least 3 months prior to sampling (see Participation of
Women below)

Participation of Women:

Contraception:

Because menstruation is known to affect the vaginal microbiome and because oral
contraceptives produce predictable menstrual cycles, subjects must be on oral
contraceptives in order to be eligible for the study. Additionally, since amoxicillin may
theoretically reduce the efficacy of oral contraceptives, subjects must agree to use an
additional form of contraception (barrier method, abstinence) while receiving the study
drug.

EXCLUSION CRITERIA:

A subject will not be eligible if she has any of the following:

- Pregnancy

- Breastfeeding

- Known allergy to beta-lactam antibiotics (e.g., penicillin)

- Body mass index (BMI) greater than or equal to 35 or less than or equal to 18 at
screening visit

- Vital signs outside of acceptable range at screening visit (i.e. blood pressure >
160/100, oral temperature > 100 degrees F, pulse > 100)

- Primary or acquired immunodeficiency, including Human Immunodeficiency Virus (HIV)
(diagnosed via an FDA-approved test)

- Hepatitis C seropositivity or positive Hepatitis B surface antigen

- Chronic, clinically significant (requiring on-going medical management or medication)
pulmonary, cardiovascular, dermatologic, endocrine, gastrointestinal, hepatic or renal
functional abnormality, as determined by medical history and physical examination
and/or laboratory testing (Complete blood count [CBC] with differential, Acute Care
Panel, Hepatic Panel)

- Active malignancy or history of malignancy for which there is not reasonable assurance
of sustained cure

- Major surgery of the gastrointestinal tract, including any major bowel resection at
any time, with the exception of cholecystectomy and appendectomy, in the past five
years

- Genitourinary/Gynecologic conditions, including:

1. Urinary incontinence necessitating use of incontinence protection garments

2. Treatment for or suspicion of ever having had toxic shock syndrome

3. History of hysterectomy

4. History of vulvar, vaginal or cervical dysplasia within the previous 5 years

5. History of condyloma or human papillomavirus (HPV) diagnosed within the previous
2 years

6. History of candidiasis, urinary tract infection, or STD (specifically chlamydia,
gonorrhea, syphilis, genital herpes, trichomoniasis) diagnosed within the
previous 6 months

7. Evidence (by history or physical exam) of vulvar or vaginal irritation at
screening

- Chronic smokers and subjects who use smokeless tobacco products (due to known effects
of tobacco on the oral microbiome)

- Exposures to the following agents (which could affect the microbiome) within 6 months
prior to sampling:

1. Systemic antibiotics, antifungals, antivirals or antiparasitics (intravenous
(IV), intramuscular (IM) or oral)

2. Vulvar/vaginal antifungal or hormonal medications

3. Intrauterine device (IUD) or hormonal vaginal ring (e.g. Nuvaring) due to unknown
duration of local hormone effects

4. Oral, IV, IM, nasal or inhaled corticosteroids, or use of high-dose topical
steroids in areas to be sampled

5. Immunosuppressive or immune-modulating agents, such as cytokines, methotrexate or
other chemotherapies

6. Large doses of commercial probiotics (greater than or equal to 10(8) cfu/day)
(ordinary fermented beverages/milks/yogurts/foods are acceptable)

7. Intranasal influenza vaccination due to effects on mucosal immunity

- Any medical, psychiatric, social condition, occupational reason or other
responsibility that, in the judgment of the investigator, is a contraindication to
protocol participation or impairs a volunteer s ability to give informed consent

- Creatinine clearance < 50 mL / min