New technology is needed to deliver multiple antiretroviral drugs in a controlled and sustained manner from intravaginal rings (IVR). Now US researchers have developed an IVR with polymer-coated drug pods that release drug directly into the vaginal mucosa
When tested in macaque monkeys, the ring continuously delivered three drugs — tenofovir, emtricitabine and maraviroc — at controlled rates over 28 days. No adverse events or toxicity were observed, and the immune system and vaginal microbiota were unaffected.
Antimicrobial Agents and Chemotherapy, the authors, led by Marc Baum of the Oak Crest Institute of Science, Pasadena, California, say the pod/intravaginal rings have the potential to prevent vaginal HIV acquisition and merit clinical investigation.
 Moss JA et al. Antimicrob Agents Chemother 2014; doi:10.1128/AAC.02871-14.