Another disappointing note was bellowed out this month concerning the discontinuation of part of a significant HIV prevention trial in women. The 1% tenofovir (Viread) gel arm of the VOICE phase 2B clinical trial was halted early by the independent Data and Safety Monitoring Board (DSMB).
The VOICE (Vaginal and Oral Interventions to Control the Epidemic) trial is a five-arm clinical trial that was launched in 2009 to evaluate the safety and effectiveness of two antiretroviral (ARV)-based approaches to preventing sexual transmission of HIV in women: applying a vaginal gel daily, or taking an ARV tablet once a day. The study, which enrolled 5,000 women from Uganda, Zimbabwe and South Africa, also seeks to determine which of the two approaches women are more likely to utilize. VOICE includes two substudies: VOICE B (Bone Mineral Density) and VOICE C (Household and Community Level Factors Associated With Study Product Adherence).
The Nov. 25 press release from AVAC: Global Advocacy for HIV Prevention stated that, at this time, researchers don't know why the 1% tenofovir gel was not effective in the prevention of HIV transmission. Past studies such as CAPRISA found a 1% tenofovir vaginal gel effective for HIV prevention in women, but not so in the VOICE trial.
The DSMB in September had already stopped the oral tenofovir arm of the study, because in the context of the study it was determined that it could not be shown to be effective. VOICE will continue to evaluate oral tenofovir/emtricitabine (Truvada), with final results expected late in 2012.
What we as providers can do:
- Keep abreast of expected data releases on VOICE.
- Stay tuned for FACTS 001, a phase 3 clinical trial with active enrollment, which strives to reach a minimum of 2,200 women in South Africa to evaluate 1% tenofovir gel with a different dosing strategy than VOICE.
- Push for more microbicide/PrEP studies on women in the United States.
Although this news may seem like a bad Italian opera with small subtitles, the aria isn't over. Continue to raise your VOICE after a little rest, lemon and honey.