Multipurpose prevention technologies: biomedical tools to prevent HIV-1, HSV-2, and unintended pregnancies

Abstract

Statistics clearly show an unmet need for highly effective contraception, especially in less developed countries. Many of these countries are at the core of the HIV/AIDS epidemic and show very high prevalence rates for other sexually transmitted infections (STIs) such as that caused by HSV-2. A woman at risk of unintended pregnancy due to unprotected intercourse is also at risk for HIV/STI. Owing to their causative interrelationship, combining protection against these conditions will result in enhanced prevention and health benefits. Existing multipurpose prevention modalities such as condoms and physical barriers, albeit efficacious, face cultural hurdles that have so far hindered their widespread use. Success has recently been demonstrated in large clinical trials, demonstrating proof of concept of microbicides in reducing the incidence of HIV-1 and HSV-2 among at-risk populations. The challenge heretofore is to refine these products to make them more potent, convenient, accessible, and acceptable. Potent antiviral drugs released topically in the female reproductive tract by innovative delivered systems and formulations will provide safe, effective, and acceptable multipurpose prevention tools. This paper provides an overview of existing and novel approaches to multipurpose prevention strategies.

Figure 1

Design of the FC1 and the FC2.

Figure 2

PATH Woman's Condom.

Figure 3

The SILCS diaphragm.

Figure 4

Segmented intravaginal ring for codelivery of tenofovir (long white segment) and levonorgestrel (short segment). Photo courtesy of Dr. Patrick Kiser (University of Utah).