maraviroc + atazanavir + ritonavir

This is a combination regimen of three antiretroviral drugs used in the treatment of HIV-1 infection. - **Maraviroc** is a small molecule entry inhibitor that acts as a selective antagonist of the human CCR5 chemokine receptor, blocking HIV-1 from entering CD4+ T-cells by preventing interaction with viral gp120[2][4][5]. - **Atazanavir** is an azapeptide HIV-1 protease inhibitor that prevents the maturation of infectious virions by inhibiting virus-specific processing of Gag and Gag-Pol polyproteins in infected cells[6][9]. It requires pharmacokinetic boosting to achieve effective plasma concentrations. - **Ritonavir** is itself an HIV protease inhibitor but is primarily used here as a pharmacokinetic enhancer (booster) due to its potent inhibition of CYP3A-mediated metabolism, thereby increasing plasma levels and efficacy of atazanavir[8]. This combination does not have a unique brand name or fixed-dose co-formulation; it represents a regimen where each drug is administered separately but together as part of highly active antiretroviral therapy (HAART). The primary indication for this combination is the treatment of CCR5-tropic HIV-1 infection in adults, particularly when resistance or intolerance limits other options.