non-nucleoside reverse transcriptase inhibitor + protease inhibitor + integrase strand transfer inhibitor

This refers to a combination regimen containing three classes of antiretroviral drugs used in the treatment of HIV infection: - Non-nucleoside reverse transcriptase inhibitors (NNRTIs) inhibit HIV-1 reverse transcriptase by binding to an allosteric site, preventing viral RNA from being transcribed into DNA. - Protease inhibitors (PIs) block the activity of HIV protease, an enzyme necessary for the maturation of infectious viral particles. - Integrase strand transfer inhibitors (INSTIs) prevent integration of viral DNA into the host genome by inhibiting the integrase enzyme. Such a combination is not available as a single fixed-dose tablet or branded product but may be prescribed as part of individualized regimens for patients with resistant virus or special clinical circumstances. Each component targets a different stage in the HIV replication cycle, providing potent suppression and reducing risk of resistance development[2][3][7].