ICAAC 2015: Combination Vaginal Ring May Be Able to Prevent Both HIV and Herpes


An experimental silicone vaginal ring with separate compartments may be able to deliver both tenofovir for prevention of HIV infection and acyclovir for prevention of genital herpes and potentially other sexually transmitted infections (STIs), according to a report at the 55th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) last weekin San Diego.

Meriam Memmi from University Jean Monnet in Saint-Etienne, France, and colleagues described the development of a silicone vaginal ring composed of multiple reservoirs. Such a product could play a role in preventing HIV and sexually transmitted diseases among women -- especially young women in Africa where HIV and STD prevalence is high and women need a method under their own control, Memmi suggested. Similar technology could also potentially include a contraceptive to prevent pregnancy.

The experimental ring consists of 2 halves containing 200 mg of tenofovir (a component of the Truvada pill used for pre-exposure prophylaxis or PrEP) and acyclovir. After adjusting the composition of the ring so it could allow the release of hydrophilic antiviral drugs, preliminary results showed that the rings could release drug concentrations between 3-5 mg/day for tenofovir and 1.5-3.5 mg/day for acyclovir for a period of at least 50 days, indicating that the ring could be used continuously for a month or more.

"The aim of our study was to develop a vaginal silicone ring that was non-toxic to the health of users but was capable of delivering multiple active antiviral molecules against various STIs including HIV for a long duration," Memmi stated in an American Society for Microbiology press release. "We succeeded in creating a ring that can deliver hydrophilic molecules such as tenofovir, active on HIV-1, and acyclovir, active on herpes virus, despite the fact that silicone is a hydrophobic compound."

Memmi said that the ring would next be tested in macaque monkeys, after which it could progress to clinical trials in women if it shows promising safety and efficacy.

Memmi described her study results during an episode of "ASM Live," broadcast from the conference.



M Memmi, M Desloir, B Figueroa, et al. Kinetics of Release of Antiviral Drugs Through a Silicone Ring. 55th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC). San Diego, September 17-21, 2015. Abstract H-775.

Other Source

American Society for Microbiology. Silicone Vaginal Rings to Deliver Antiviral Drugs, Protect Women against HIV. Press release. September 19, 2015.