DSMB Recommends maraviroc phase 2b/3 studies continue as designed
Pfizer today said that the independent Data Safety Monitoring Board (DSMB)
for maraviroc, a CCR5 antagonist in development for the treatment of HIV,
met in July and again in September of 2005 and recommended that all Phase
2b/3 clinical studies in antiretroviral-naïve and antiretroviral-experienced
patients for the investigational medicine continue as currently designed.
The DSMB delivered these assessments after comprehensive reviews of
maraviroc efficacy, safety, and laboratory data (including hepatic enzyme
abnormalities). In July they reviewed data from all studies in
antiretroviral-naïve and antiretroviral-experienced patients and in
September reviewed data from the study in antiretroviral-naïve patients and
one of the studies in treatment-experienced patients. Maraviroc clinical
trials have been ongoing since November 2004 and have enrolled more than
1000 patients to date. A proportion of patients have exceeded 24 weeks of
The maraviroc DSMB is an independent group that includes experts who
specialize in the treatment of patients with HIV/AIDS.
CCR5-antagonists block HIV from entering white blood cells, where the virus
replicates. In the absence of entry inhibitors, HIV can enter white blood
cells, take over the cell’s DNA for its own reproduction, and ultimately
destroy a patient’s immune system.