Currently, efficacious treatment of human beings infected with HIV is best accomplished by use of a mixture or cocktail of different drugs that act as inhibitors of key enzymes that control cocktail are the HIV Specific Protease inhibitors such as Nelfinavir and Indinavir. Immunoassay analysis of Indinavir and Nelfinavir would provide an analytical suitable, clinically useful therapeutic monitoring methodology. Florescence polarization immunoassays (FPIA) represent a suitable method for these types of measurements that has proven especially useful and cost effective in monitoring anti infectives. Two milestones are extant in this proposal: (1) Preparation of the poly/monoclonal immunoreagents and fluorescent tracers used in FPIA and (2) Demonstration of the feasibility and suitability of those reagents in an automated assay paradigm. This Phase I SBIR has high program relevance to the mission of the National Institute for Allergy and Infectious Disease (NIAID) and the National Cancer Institute (NCI). PROPOSED COMMERCIAL APPLICATION: Measurement for HIV Protease Inhibitors will become a standard of treatment in the application of these drugs in HIV. Providing a cost effective and efficient analytical methodology, such as FPIA), to provide that measurement will greatly enhance the efficacious use of these drugs.