atazanavir + saquinavir + tenofovir + nucleoside

This is a combination antiretroviral therapy regimen consisting of atazanavir, saquinavir, tenofovir, and a nucleoside reverse transcriptase inhibitor (NRTI). All four components are small molecule drugs used in the treatment of HIV-1 infection. Atazanavir and saquinavir are protease inhibitors that block the HIV-1 protease enzyme, preventing viral replication. Tenofovir is a nucleotide reverse transcriptase inhibitor (NtRTI) that inhibits HIV reverse transcriptase by competing with natural substrates and causing DNA chain termination. The "nucleoside" component refers to an additional NRTI (such as lamivudine or emtricitabine), which also inhibits reverse transcriptase by incorporation into viral DNA. This combination targets multiple steps in the HIV replication cycle to reduce viral load and delay resistance development[2][3][10].