Cobicistat (GS-9350) is a potent, and selective inhibitor of human cytochrome P450 3A (CYP3A) enzymes. Cobicistat is a pharmacokinetic booster of several antiretrovirals. TYBOST (cobicistat) is indicated to increase systemic exposure of atazanavir or darunavir in combination with other antiretroviral agents in the treatment of HIV-1 infection.

Darunavir (trade name Prezista) is an orally active bis-furan-sulfonamide inhibitor of human immunodeficiency virus (HIV-1) protease. Darunavir was developed by Tibotec Pharmaceuticals (now Janssen R&D Ireland). Darunavir is indicated for the treatment of HIV-1 infection in adult and pediatric patients 3 years of age and older. The drug is co-administered with low-dose ritonavir and other anti-HIV agents. It is the only antiretroviral that has been registered at two different doses, 800/100 mg once-daily or 600/100 mg twice-daily, allowing its administration throughout the entire course of HIV disease, from naive subjects without any HIV-1 resistance to heavily treatment-experienced subjects with widespread triple-class family resistance.

(R)-9-(2-Phosphonylmethoxypropyl)adenine (PMPA known as tenofovir) is an antiviral drug. Diphosphate of PMPA acts as a selective inhibitor of the HIV-1 reverse transcriptase. Tenofovir disoproxil was approved for clinical use for the treatment of HIV infection (AIDS) and chronic HBV infection.