HIV Prevention by Enhancing the Effectiveness of Tenofovir Gel Microbicide

Background:  To build on the partial success of Tenofovir gel

Objectives:  (A) Prevent HIV/STIs by using a cervical barrier to deliver microbicide. (B) Prevent pregnancy and thus prevent mother-to child HIV transmission. (C) Enhance adherence, retention and efficacy of Tenofovir microbicide.

Methods: We investigated the feasibility of an FDA-approved cervical barrier device that delivers microbicide on its cervical and vaginal sides, to be used to deliver Tenofovir. We evaluated acceptability, adherence and retention of a stained vaginal lubricant (substituted for Tenofovir) delivered by the cervical barrier versus delivery with the vaginal applicator utilized in the CAPRISA 004 study. Thirty women compared using a vaginal applicator to deliver a high-viscosity vaginal lubricant stained with Gentian violet before and after intercourse to using the cervical barrier to deliver the lubricant before intercourse only. We then used colposcopy to study gel retention over the cervix and vagina.

Results:  Twelve women (40%) missed applying the lubricant with the vaginal applicator before intercourse; 10% missed it after intercourse.  Three cervical barrier users (10%) missed applying the lubricant before intercourse, and all of them inserted it after intercourse. The gel was better retained over the cervix by a single application with the cervical barrier versus two applications using the vaginal applicator.

Conclusions: Study participants preferred one gel application using the cervical barrier to two applications using the vaginal applicator based on ease of use and elimination of lubricant leakage. We conclude that utilizing the cervical barrier can prevent pregnancy and mother-to-child HIV transmission, while enhancing compliance and retention of gel over the cervix to potentially prevent STIs and increase the efficacy of Tenofovir.

Implications for Programs, Policy, and Research:  If this simple method can reduce the risk of STI/HIV transmission by only 10%, it would have an enormous impact world-wide.