New microbicide gel formulation shows promise for safe vaginal and rectal administration to prevent HIV

Researchers developed a first-of-its-kind microbicide gel formulation that shows promise for safe vaginal and rectal administration to prevent the sexual transmission of human immunodeficiency virus (HIV). This research is being presented at the 2013 American Association of Pharmaceutical Scientists (AAPS) Annual Meeting and Exposition, the world's largest pharmaceutical sciences meeting, in San Antonio, Nov. 10-14.

There are 35.3 million people living with HIV worldwide, according to the World Health Organization, and the virus is spread most often through both vaginal and anal intercourse.

Anthony Ham, Ph.D., and the microbicide research team at ImQuest BioSciences, along with colleagues from Duke University, Magee-Womens Hospital, and University of Pittsburgh, developed the DuoGel as a task of their Integrated Preclinical and Clinical Program for Topical Microbicides grant from the National Institutes of Health. The primary goal was to create a safe and effective gel for administration of antiviral products to both the vagina and rectum, whereas current gels are only recommended for vaginal application. This DuoGel will deliver ImQuest's antiretroviral compound IQP-0528.

Since the environments of the vagina and rectum are dissimilar and require different conditions for safe and effective drug delivery, ex vivo toxicity, permeability, and efficacy tests were performed in both ectocervical and colorectal tissues. The DuoGel containing IQP-0528 was applied to the tissues, which were then exposed to HIV-1. The gel sufficiently delivered the drug in both in vitro and ex vivo vaginal and rectal environments to prevent HIV-1 infection of these tissues.

"It is recognized that both vaginal and rectal intercourse occur during the same sexual act, so a single product that is safe for both compartments makes sense in terms of convenience, which is likely to result in higher compliance." said Ham. "In addition, these DuoGels will be much safer products for HIV prevention in males practicing receptive anal intercourse."

Currently, user compliance and acceptability are being evaluated with a placebo DuoGel. The research team is preparing the current gel for animal studies and Investigational New Drug submission, and they hope to begin phase 1 of clinical trials in early 2015. The next stage in the research is to enhance the formulation by creating a multidrug DuoGel that also contains tenofovir, a second antiretroviral drug.

The 2013 AAPS Annual Meeting and Exposition aims to improve global health through advances in pharmaceutical sciences, and there will be 480 exhibits and an estimated 8,000 attendees. The meeting features nearly 105 programming sessions, including more than 50 symposia and roundtables. Download the AAPS smartphone application for additional information.

Source: American Association of Pharmaceutical Scientists