Emtricitabine and tenofovir alafenamide belong to a class of drugs called nucleoside reverse transcriptase inhibitors (NRTIs). Elvitegravir belongs to a class of drugs called integrase inhibitors (INSTIs). Cobicistat belongs to a class of drugs called pharmacokinetic enhancers.
Mylan A4 works by blocking different steps in the HIV-1 replication cycle. Emtricitabine and tenofovir alafenamide block the enzyme reverse transcriptase, which is needed for HIV-1 to make copies of itself. Elvitegravir blocks the enzyme integrase, which is needed for HIV-1 to insert its genetic material into human cells. Cobicistat increases the levels of elvitegravir in the blood by blocking an enzyme that breaks down elvitegravir.
Mylan A4 is usually taken once daily with or without food. It is important to take Mylan A4 exactly as prescribed by your doctor and to continue taking it even if you feel well.