Exploratory Pharmacodynamic Study of Tenofovir-Based Products

This study will compare an investigational intravaginal ring containing tenofovir (TFV) with
an FDA approved medication in tablet form called Truvada®. It will assess and compare the
ability of the tablet and intravaginal ring to prevent HIV transmission (human
immunodeficiency virus, the virus that causes AIDS).

The study will enroll healthy, non-pregnant, HIV negative, premenopausal women (aged 18-50,
with regular menstrual cycles) who are not at risk of pregnancy.

The enrollment goal is for 20 participants to complete the study.

Participants will be assigned to use one of the study products: oral tablet or intravaginal
ring. Participants will take the oral tablet each day for 14 days or wear the intravaginal
ring all day and night for 14 days/nights. Blood, genital fluid samples and genital tissue
samples (biopsies) will be taken at two visits. These sample collections will take place
before and after use of the assigned study product. The samples will be tested to:

1. Determine the levels of drug in the blood and genital tissue samples

2. See if the samples taken from the vagina and cervix after use of study product,
provides protection from HIV in the laboratory

3. Ensure that the laboratory test used to measure HIV infection in the samples performs
well when used repeatedly.

Inclusion Criteria:

- General good health (by volunteer history and per investigator judgment) without any
clinically significant systemic disease (including, but not limited to significant
liver disease/hepatitis, gastrointestinal disease, kidney disease, thyroid disease,
osteoporosis or bone disease, and diabetes) and with an intact gastrointestinal
tract, uterus and cervix

- Currently have regular menstrual cycles of 21-35 days by participant record

- Willing to abstain from vaginal intercourse and any other vaginal activity including
use of vaginal products (tampons, spermicides, lubricants, and douches) other than
study products:

- 48 hours before Visit 2 until six days after Visit 2

- 48 hours before Visit 3 until six days after Visit 4

- Vaginal and cervical anatomy that, in the opinion of the investigator, lends itself
to easy genital tract sample collection

- Estimated calculated creatinine clearance (eCcr) of at least 60 mL/min

- History of Pap smears and follow-up consistent with standard clinical practice as
outlined in the study manual or willing to undergo a Pap smear at Visit 1

- Protected from pregnancy by one of the following:

- sterilization of either partner

- abstinence

- same sex relationship

- condoms

- combined contraceptives (including oral, patch)

- copper IUD

- Willing and able to comply with protocol requirements including swallowing tablets

- Willing to give voluntary consent and sign an informed consent form

Exclusion Criteria:

- History of hysterectomy

- Currently pregnant or within two calendar months from the last pregnancy outcome.
Note: if recently pregnant must have had at least two spontaneous menses since
pregnancy outcome

- Injection of Depo-Provera in the last 10 months or use of other progestin-only based
contraceptive (including hormonal IUD)

- Currently breastfeeding or planning to breastfeed during the course of the study

- History of sensitivity/allergy to any component of the study products, topical
anesthetic, or to both silver nitrate and Monsel's solution

- In the last three months, diagnosed with or treated for any STI, by self report

- Positive test for Trichomonas vaginalis, Neisseria gonorrhea, Chlamydia trachomatis,
HIV, or Hepatitis B surface antigen (HBsAg) Note: Women with a history of genital
herpes who have been asymptomatic for at least three months may be considered for
eligibility

- Chronic or acute vulvar or vaginal symptoms (pain, irritation, spotting/bleeding,
discharge, etc.)

- Known bleeding disorder that could lead to prolonged or continuous bleeding with
biopsy

- Systemic use in the last two 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, or antivirals (e.g., acyclovir,
valacyclovir, Viread®, Atripla®, Emtriva®, or Complera®)

- Current or anticipated chronic use of NSAIDS, or Tylenol for the duration of the
study

- Grade 2 or higher laboratory abnormality, per the 2014 update of the Division of
AIDS, National Institute of Allergy and Infectious Disease (DAIDS) Table for Grading
the Severity of Adverse Events, or clinically significant laboratory abnormality as
determined by the clinician

- Abnormal finding on laboratory or physical examination or a social or medical
condition in either the volunteer or which, in the opinion of the investigator, would
make participation in the study unsafe or would complicate interpretation of data

- Known current drug or alcohol abuse which could impact study compliance

- Participation in any other investigational trial within the last 30 days 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