Advances in development, scale-up and manufacturing of microbicide gels, films, and tablets

Vaginal HIV microbicides are topical, self administered products designed to prevent or significantly reduce transmission of HIV infection in women. The earliest microbicide candidates developed have been formulated as coitally dependent (used around the time of sex) gels and creams. All microbicide candidates tested in Phase III clinical trials, so far, have been gel products with non-specific mechanisms of action. However, recently, research is focusing on compounds containing highly potent and specific anti-retrovirals. These specific anti-retrovirals are being formulated as primary dosage forms such as vaginal gels or in alternative dosage forms such as fast dissolve films and tablets. Recent innovations also include development of combination products of highly active antiviral drugs such as reverse transcriptase inhibitors and entry inhibitors, which would theoretically be more effective and would reduce the possibility of drug resistance. In this article, an overview of recent advances in the microbicide gel, film, and tablet formulations and issues pertaining to scale-up, formulation, and evaluation challenges and regulatory guidelines have been presented. This article forms part of a special supplement covering presentations on gels, tablets, and films from the symposium on "Recent Trends in Microbicide Formulations" held on 25 and 26 January 2010, Arlington, VA.