Topical Microbicides for Prevention of Sexually Transmitted Infections
Obiero, J., Mwethera, P.G., & Wiysone, C.S. Cochrane Database of Systematic Reviews (June 2012), 6(CD007961).
The authors of this systematic review found that by the end of 2011, nine randomized controlled trials (RCTs) enrolling 31,941 sexually active women in 11 countries, with HIV incidence as the primary outcome, had demonstrated limited evidence that vaginal microbicides reduce acquisition of HIV and herpes simplex virus (HSV-2) infection in women. As a result, the authors do not recommend topical microbicides for HIV or STI prevention, but do suggest that development of new microbicides continue. Of the nine RCTs, the authors found that CAPRISA 004, a small proof-of-concept RCT enrolling 889 women, demonstrated that tenofovir—a nucleotide reverse transcriptase inhibitor—may reduce the risk of acquiring HIV and HSV-2. The authors are currently awaiting data from a second tenofovir trial enrolling 5,000 women, which was stopped early due to futility of results demonstrating a protective effect. According to the authors, other types of topical microbicides did not demonstrate a reduction in the risk of acquiring HIV or sexually transmitted infections (STIs), and none of the trials demonstrated that microbicides reduce the acquisition of other STIs, including gonorrhea, syphilis, genital warts, trichomoniasis, or human papillomavirus infection. The authors stress that if further studies demonstrate the effectiveness of tenofovir-based microbicides, efforts must be made to achieve rapid regulatory approval and create appropriate mechanisms for distribution.