The Division of AIDS (DAIDS) of the National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), maintains a portfolio of contracts to support the development of (1) therapies for HIV infection and its complications and coinfections, and (2) microbicides for preventing the sexual transmission of HIV. Services provided under this contract assist investigators in academic settings and small pharmaceutical firms in filling specific gaps in their drug development plan as they advance their product towards clinical investigation of therapies for HIV infection and interventions to prevent HIV transmission. Activities will include the development of formulations of potential therapeutic agents and microbicides. In addition studies will be conducted to assess the pharmacology and toxicology of potential therapeutic agents and microbicides. This project will support the following activities: Toxicology studies of tenofovir nanformulation with pharmacokinetics in mice; inhalation studies with clofazimine in ratsl and development of mitochondrial toxicity assays for mitochondrial toxicity assessment