efavirenz/emtricitabine/tenofovir disoproxil fumarate

A fixed combination of efavirenz, a non-nucleoside reverse transcriptase (RT) inhibitor (NNRTI); emtricitabine, a nucleoside RT inhibitor (NRTI) analog of cytidine; and tenofovir disoproxil fumarate, an NRTI analog of adenosine monophosphate, that is used to treat human immunodeficiency virus (HIV) infection. Upon oral administration, efavirenz, emtricitabine, and tenofovir disoproxil fumarate inhibit the activity of HIV RT by competing with natural deoxyribonucleosides for incorporation into the growing viral DNA chain resulting in early chain termination. This interferes with the generation of DNA copies of viral RNA, which is necessary for the synthesis of new virions.