SCHERING-PLOUGH RELEASES DATA FROM HIV DRUG STUDY

Schering-Plough has reported that results from an ongoing Phase II clinical trial showed vicriviroc, its investigational CCR5 receptor antagonist, demonstrated potent and sustained viral suppression after 24 weeks of therapy in 118 treatment-experienced HIV patients, when administered in once-daily doses in combination with an optimized ritonavir-boosted protease inhibitor (PI)-containing antiretroviral regimen.

In the study, viral load decrease was significantly greater for patients in each vicriviroc group compared with the control group at day 14 and at week 24, and was not different between the vicriviroc groups. Although there was no statistical difference in the viral load reductions between the three vicriviroc arms, a higher rate of virologic failure and emergence of X4 virus was observed at the lowest dose of 5 mg. This is the first trial with a CCR5 receptor antagonist for HIV to report 24-week treatment results.

A total of 118 heavily treatment-experienced HIV patients with R5-type virus taking ritonavir-boosted PI-containing regimens were randomized in the double-blind, 48-week study. Change in viral load after addition of vicriviroc dosed once daily or placebo was measured at 14 days, and then at 12 and 24 weeks, after the background antiretroviral regimen had been optimized at day 14.