An anti-HIV cream applied to the vagina or rectum could target the incoming virus and either permanently inactivate it or reduce its infectivity. Several promising molecules have been identified, but the topical efficacy of these compounds has been unclear. In the February 10
Veazey et al. performed a series of comparative experiments using SHIV-162P4 vaginal infection of depo-medroxyprogesterone acetate (Depo-Provera)-treated rhesus macaques. They observed that only three of 12 animals receiving 5 mg b12 vaginally in either saline or a gel became infected. However, infection occurred in 12 of 13 animals given various control agents under similar conditions. In addition, they showed that ...