Vignette: A 27-year-old male presents to the clinic with fatigue, weight loss, and chronic diarrhea. On physical examination, oral thrush is noted. A blood draw reveals CD4+ T cell count of 185 cells/uL. The patient is diagnosed with HIV infection and started on antiretroviral therapy. The mechanism of action of one of the medications he is started on includes blocking of the viral protein that is responsible for the formation of a polyprotein precursor to the viral core proteins.
Which of the following medications was most likely started in his treatment regimen?
Lopinavir is a protease inhibitor, which works by preventing the cleavage of the HIV-1 gag-pol polyprotein into individual functional proteins that are necessary for the assembly of new virions. This leaves the virus unable to mature and become infectious. Other protease inhibitors include atazanavir, darunavir, and ritonavir.
Efavirenz (Choice A) is a non-nucleoside reverse transcriptase inhibitor, which blocks reverse transcriptase and prevents the conversion of viral RNA into DNA. Abacavir (Choice B) is a nucleoside reverse transcriptase inhibitor, which is incorporated into the viral DNA and causes chain termination. Raltegravir (Choice C) is an integrase inhibitor, which prevents the integration of the viral DNA into the host cell's DNA. Maraviroc (Choice D) is a CCR5 antagonist, which blocks the binding of HIV gp120 to the CCR5 receptor, preventing viral entry into the cell.