NELVIR Tablets NELVIR contains Nelfinavir Mesylate, an orally bioavailable non-peptidic inhibitor of the Human Immunodeficiency Virus Type 1 (HIV-1) protease enzyme. Nelfinavir selectively binds to the active site of HIV-1 protease and prevents the cleavage of viral Gag-Pol polyprotein precursors. This inhibition blocks the maturation of viral particles, resulting in the release of immature, non-infectious virions. It is indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection in adult and pediatric patients.