Antiretroviral Drugs

Introduction

• Antiretroviral (ARV) drugs are agents active against HIV, a lentivirus (retrovirus subfamily). They suppress replication and prolong life but do not cure — because the HIV genome integrates into host DNA, eradication is impossible with current agents.
• Goal of therapy — maximal, durable suppression of plasma HIV-RNA to undetectable (<20–50 copies/mL) with a rise in CD4 count; the deeper the suppression, the lower the risk of resistance. With early, adherent ART, life expectancy approaches that of an uninfected person.
• Treatment is lifelong, complex and adherence-critical; combination therapy (≥3 drugs from ≥2 classes) is mandatory — monotherapy is contraindicated.
• Two species — HIV-1 (global epidemic) and HIV-2 (West Africa, less virulent). Most ARVs cover both except NNRTIs and enfuvirtide, which are HIV-1-specific.