Maraviroc Effective in Previously Treated HIV Cases
Phase 3 studies show significant suppression of HIV-1 and increased CD4 cell count
WEDNESDAY, Oct. 1 (HealthDay News) -- Maraviroc -- one of a new class of drugs that bind to the human chemokine receptor 5 and interfere with viral replication -- may be an effective treatment for previously treated patients with R5 HIV-1 infection, according to two studies published in the Oct. 2 issue of the New England Journal of Medicine.
In one study, Roy M. Gulick, M.D., of the Weill-Cornell Medical College in New York City, and colleagues conducted two double-blind, placebo-controlled, phase 3 studies -- Maraviroc versus Optimized Therapy in Viremic Antiretroviral Treatment-Experienced Patients (MOTIVATE) 1 and MOTIVATE 2 -- in which 1,049 patients with R5 HIV infection on optimized background therapy were randomly assigned to receive the study drug or placebo. After 48 weeks, the investigators found that maraviroc was associated with significantly greater suppression of HIV-1 and greater increases in CD4 cell counts than optimized background therapy alone.
In a second study, Gerd Fatkenheuer, M.D., of the Universitatsklinik Koln in Cologne, Germany, and colleagues conducted a subgroup analysis of MOTIVATE 1 and 2 "according to sex, race or ethnic group, clade, CC chemokine receptor 5 (CCR5) delta32 genotype, viral load at the time of screening, the use or non-use of enfuvirtide in optimized background therapy, the baseline CD4 cell count, the number of active antiretroviral drugs co-administered, the first use of selected background agents, and tropism at baseline." They found that maraviroc was associated with a treatment benefit in all the subgroups.
"The availability of a new class of anti-HIV drugs is a most welcome addition to the armamentarium against the virus," states the author of an accompanying editorial. "Optimal use is a challenge that will require continued study and vigilance by investigators, clinicians and patients themselves."
MOTIVATE 1 and MOTIVATE 2 were sponsored by Pfizer Global Research and Development.