With the Food & Drug Administration's approval of Atripla (efavirenz/emtricitabine/tenofovir, Bristol-Myers Squibb and Gilead Sciences), HIV patients will have access to a once-daily single-tablet regimen. The new product combines three agents from two classes of antiretrovirals: Efavirenz (600 mg) is a non-nucleoside reverse transcriptase inhibitor (NNRTI); and emtricitabine (200 mg) and tenofovir (300 mg) are nucleoside reverse transcriptase inhibitors (NRTIs). All three work by blocking reverse transcriptase, an enzyme required for HIV replication.
