Reduced Antiretroviral Drug Susceptibility Among Patients With Primary HIV Infection

Abstract

Antiretroviral (ARV) drug resistance is associated with diminished responses to treatment^1-3 and increased mortality^3,4 in patients with established human immunodeficiency virus (HIV) infection. The transmission of single drug–resistant^5,6 and multidrug-resistant^7,8 virus has been documented, although the overall frequency of these events in the United States is unknown. Persistent viral replication (plasma HIV RNA >500 copies/mL) is observed in 10% to 40% of therapy-naive subjects with established infection treated for 24 weeks with potent ARV therapy.^9-11 More widespread use of these potent regimens among infected patients at both early and later stages of infection¹² may increase the number of individuals in whom drug resistance is selected during therapy and perhaps increase the population-based risk for transmission of resistant HIV. Furthermore, the use of a suboptimal initial treatment regimen in a person infected with drug-resistant virus is expected to limit the magnitude and durability of an antiviral response and may preclude the preservation of HIV-specific immune responses associated with early, effective ARV therapy.¹³ Prospective studies are needed to evaluate the clinical significance of primary HIV infection with drug-resistant virus and the subsequent virological response to ARV therapy.