In Vivo Drug Interaction Pharmacokinetic Study of Tenofovir 1% Gel and Three Commonly Used Vaginal Products

Inclusion Criteria:

• Age 18-50 years, inclusive
• General good health (by volunteer history and per investigator discretion)
• History of and currently regular menstrual cycles
• Willing to abstain from the use of vaginal products, other than the TFV gel and her assigned study vaginal product for the duration of the study.
• Willing to abstain from sex and other vaginal activity during each crossover period starting 72 hours prior to initiating product use, for the duration of use, and until the sixth day following sample collection
• At low risk for pregnancy due to surgical sterilization of participant and/or her sexual partner, use of copper IUD or male condom, abstinence, or same sex relationship
• Vaginal and cervical anatomy that, in the opinion of the investigator, lends itself to easy genital tract sample collection
• History of Pap smears and follow-up consistent with ACOG practice guidelines
• Negative urine pregnancy test
• Willing to give voluntary consent, sign an informed consent form and comply with study procedures as required by the protocol

Exclusion Criteria:

• History of hysterectomy
• Currently pregnant/within 2 calendar months from the last pregnancy outcome.
• Use of Depo-Provera in the last 120 days or any hormonal contraceptives in the last month
• Currently breastfeeding or having breastfed an infant in the last 2 months, or planning to breastfeed during the course of the study

• History of sensitivity/allergy to any component of:

  • TFV 1% gel; or
  • topical anesthetic, or allergy to both silver nitrate and Monsel's solution.
• Contraindication to any of 3 vaginal products (antifungal cream, antimicrobial gel, or the combination contraceptive vaginal ring) to which participants may be randomized
• In the last 6 months, diagnosed with or treated for any STI or pelvic inflammatory disease, by self report.
• Symptomatic BV
• Nugent score greater than or equal to 7 or positive test for Trichomonas vaginalis at Visit 1
• Positive test for Neisseria gonorrhea or Chlamydia trachomatis
• Deep epithelial genital findings, on visual examination, such as abrasions, ulcerations, and lacerations, or vesicles suspicious for a sexually transmitted infection
• Positive test for HIV
• Positive test for Hepatitis B surface antigen (HBsAg)
• Known bleeding disorder that could lead to prolonged or continuous bleeding with biopsy
• Chronic or acute vulvar or vaginal symptoms
• Known current drug or alcohol abuse which could impact study compliance
• Grade 1 or higher laboratory abnormality, per the August 2009 update of the DAIDS Table for Grading the Severity of Adverse Events
• Systemic use in the last 2 weeks or anticipated use during the study of any of the following: corticosteroids, antibiotics, anticoagulants or other drugs known to prolong bleeding and or clotting, antifungals, antivirals (e.g., acyclovir or valacyclovir) or antiretrovirals (e.g., Viread®).
• Participation in any other drug or device interventional investigational trial (device, drug, or vaginal trial) within 30 days of this study or planned participation in any other investigational trial during the study
• History of gynecological procedures (including genital piercing) on the external genitalia, vagina or cervix within the last 14 days
• Abnormal finding on laboratory or physical examination or a social or medical condition which, in the opinion of the investigator, would make participation in the study unsafe or would complicate interpretation of data