Virologic outcomes of changing enfuvirtide to raltegravir in HIV-1 patients well controlled on an enfuvirtide based regimen: 24-week results of the CHEER study.

OBJECTIVES To determine the safety and efficacy of changing enfuvirtide to raltegravir in HIV-1-infected patients with HIV-1 RNA below the level of quantification for at least 6 months on an enfuvirtide-containing antiretroviral regimen. DESIGN Prospective, nonrandomized, historical control study. METHODS Patients were recruited from 11 Kaiser Permanente HIV clinics in California. Those patients eligible for inclusion (>or=18 years old, well controlled on antiretroviral medications) had enfuvirtide changed to raltegravir 400 mg, given twice daily orally; all other background antiretrovirals remained unchanged. The primary end point was percentage of patients with HIV-1 RNA below the limit of quantification after 24 weeks of raltegravir therapy. Analyses were by intention to treat. RESULTS Fifty-two patients were enrolled in the trial. After 24 weeks of therapy with raltegravir, 49 (94.2%, confidence interval: 1.2% to 15.9%) patients had HIV-1 RNA levels below the limit of quantification. Patients had a median CD4 cell increase of 32 cells per cubic millimeter after 24 weeks of raltegravir therapy. Treatment satisfaction as measured by patient questionnaires improved with the raltegravir-containing regimen. Adverse events were infrequent and generally mild in nature. CONCLUSIONS In treatment-experienced patients on a stable virologically suppressive enfuvirtide-containing regimen, raltegravir can safely be substituted for enfuvirtide.