zidovudine + lamivudine + indinavir + ritonavir

This is a combination antiretroviral therapy regimen consisting of four drugs used for the treatment of HIV-1 infection. It combines two nucleoside reverse transcriptase inhibitors (zidovudine and lamivudine) with two protease inhibitors (indinavir and ritonavir). This combination therapy works by inhibiting different stages of the HIV replication cycle, with zidovudine and lamivudine inhibiting the reverse transcriptase enzyme, while indinavir and ritonavir inhibit the viral protease enzyme. The combination has shown effectiveness in suppressing HIV viral load and increasing CD4 cell counts in patients with HIV infection.