Microbicide delivery: formulation technologies and strategies

Purpose of review: The aim of this article is to summarize the latest information on microbicide formulations for prevention of sexual transmission of HIV infection in women. Recent findings: Although early microbicide formulations were conventionally coitally dependent gel products, new technologies are being developed for vaginal delivery of anti-HIV agents. Intravaginal rings for delivery of microbicides, for example, are being developed and evaluated clinically. Safety and acceptability data are available for many microbicide gels and for one microbicide intravaginal ring. Other microbicide formulations in development for once daily or other vaginal administration strategies include films, tablets, and ovules. Various microbicide formulations for rectal administration are also in development. Summary: New microbicide formulations in development are addressing many of the issues with the original gels such as coital dependency, frequency of use, acceptability, compliance, cost, and adaptability to large-scale production. All of these dosage forms are promising options for safe, effective, and acceptable microbicide products.