Pharmacokinetic Study of the Vaginal Microbicide Agent 1% Tenofovir Gel

Study Summary

This is a multi-center, pharmacokinetic study involving a single-dose phase, a wash out phase and a two-week once or twice-daily dosing phase for each of 49 volunteers. In the single-dose phase, each volunteer will apply the single dose in the clinic. Participants will be randomized to have cervicovaginal samples and biopsies collected at one of seven time-points \[0.5, 1, 2, 4, 6, 8, and 24 hour(s)\] after the single-dose. Blood samples will be drawn at 0.5, 1, 2, 4, 6, 8, and 24 hour(s) after the single-dose. In the two-week phase, the study supplies will be distributed and the participants will be randomized to apply each dose either once or twice-daily for two weeks. At the one week follow-up visit a blood sample will be drawn prior to the morning dose to obtain a trough value and cervicovaginal samples will be collected four hours after the morning dose. At the two week follow-up visit blood samples will be drawn prior to the morning dose to obtain a trough value and then at 0.5, 1, 2, 4, 6, 8, and 24 hour(s) from the final morning dose. Participants will be randomized to have cervicovaginal samples and biopsies collected at either 4, 8 or 24 hours after the final morning dose. Up to 10 participants who have completed the first two phases of the study, will be asked to participate in a third phase to have cervicovaginal samples, biopsies and blood samples collected 12 hours after a single-dose.

Interventions

• DRUG Tenofovir gel