Development of dapivirine vaginal ring for HIV prevention

• The NNRTI dapivirine is described for topical vaginal use for HIV prophylaxis.
• Development of a platinum-catalyzed silicone matrix vaginal ring is described.
• The potential for vaginal ring technology to have good adherence is discussed.
• Two large-scale clinical trials testing safety, efficacy and acceptability of a dapivirine vaginal ring are overviewed.

In the continuing effort to develop effective HIV prevention methods for women, a vaginal ring containing the non-nucleoside reverse transcriptase inhibitor dapivirine is currently being tested in two safety and efficacy trials. This paper reviews dapivirine ring’s pipeline development process, including efforts to determine safe and effective dosing levels as well as identify delivery platforms with the greatest likelihood of success for correct and consistent use. Dapivirine gel and other formulations were developed and tested in preclinical and clinical studies. Multiple vaginal ring prototypes were also tested, resulting in the current ring design as well as additional designs under consideration for future testing. Efficacy results from clinical trials are expected in 2015. Through ongoing consultations with national regulatory authorities, licensure requirements for dapivirine vaginal ring approval have been defined. This article is based on a presentation at the “Product Development Workshop 2013: HIV and Multipurpose Prevention Technologies,” held in Arlington, Virginia on February 21–22, 2013. It forms part of a special supplement to Antiviral Research.