Efficacy of and adherence to highly active antiretroviral therapy in children infected with human immunodeficiency virus type 1

Background Clinical trials in adults have demonstrated the efficacy of high ly active antiretroviral therapy (HAART) to suppress replication of HIV-1 t o nondetectable levels, but lower success rates have been observed in pract ice. We sought to determine the efficacy of HAART in our population of HIV- 1 infected children and to identify determinants of efficacy, especially th e role of adherence to prescribed antiretrovirals. Methods. The viral load and CD4(+) T cell responses of 72 children with per inatally acquired HIV-1 treated with HAART including a protease inhibitor f or at least 90 days were examined retrospectively in relation to adherence, as measured by pharmacy records for the first 180 days of HAART. Results. Patients were defined as adherent if greater than or equal to 75% of protease inhibitors and greater than or equal to 75% of all antiretrovir al prescriptions were filled. Of the 42 patients (58%) who were adherent, n ondetectable viral loads were achieved and maintained in 22 (52%). A Kaplan -Meier plot showed a drop-off in patients maintaining a nondetectable viral load after 200 days, Higher initial viral load was the only pretreatment f actor that identified adherent patients at risk for treatment failure. Only 3 (10%) nonadherent patients maintained a viral load of <400 copies/ml. Th e adherent group had a prompt and sustained increase in CD4(+) T cell count s. Conclusions. HAART can achieve control of viral replication in HIV-1-infect ed children who adhere to therapy. However, treatment failure is likely unl ess there is a high level of adherence. Nonadherence to therapy is common a nd might be the major impediment to successful treatment of children infect ed with HIV-1.