SCHERING-PLOUGH DISCONTINUES PHASE II STUDY OF VICRIVIROC

Schering-Plough has discontinued a Phase II study with its investigational CCR5 receptor antagonist, vicriviroc, used in combination with Combivir in treatment-naive HIV patients. This decision was due to a return of detectable virus in some patients late in therapy compared to the control regimen of Combivir and Sustiva, the current standard of care for treatment-naive patients living with HIV.

The company discontinued its Phase II treatment-naive study following a recommendation from the independent data safety monitoring board, which has been meeting regularly to conduct reviews of the safety and efficacy data. The increased incidence of detectable virus was only seen in some patients after several weeks of treatment. The study had been underway since spring 2004 in 23 centers in Europe and Canada, with 92 patients enrolled. Patients already enrolled in the treatment-naive study will continue to receive vicriviroc until they can be switched to an alternative regimen in consultation with their physician.