Multipurpose prevention approaches with antiretroviral-based formulations.

We compared the preclinical safety and efficacy of tenofovir (TFV) 1% gel with that of MZC gel [containing 50 mu M MIV-150, 14 mM Zn(O2CCH3)(2)(H2O)(2), and 3% carrageenan] through a series of in vitro, ex vivo, and in vivo assays. The two gels showed good antiviral therapeutic indexes (50% cytotoxic concentration/ 50% effective concentration ratios; range,> 25 to 800). MZC showed greater anti-simian-human immunodeficiency virus reverse transcriptase (SHIV-RT) activity than TFV 1% gel in rhesus macaque vaginal explants. MZC protected mice from vaginal herpes simplex virus 2 (HSV-2) challenge (P< 0.0001), but the TFV 1% gel did not.