Cubist Pharmaceuticals initiates dosing in Phase 2 trial with CB-183,315 for diarrhea due to CDAD

Cubist Pharmaceuticals, Inc. (NASDAQ: CBST), a leading acute care therapeutics company, today announced the enrollment and dosing of the first subject in its Phase 2 trial with CB-183,315, an antibacterial drug candidate intended to treat patients with a severe and sometimes life-threatening diarrhea caused by Clostridium difficile known as C. difficile-associated diarrhea, or CDAD. The trial is expected to enroll more than 200 subjects at 28 sites in the United States and Canada.

“This is the first Phase 2 trial emanating from Cubist's internal research efforts and hence marks an important milestone as we continue to build a portfolio of potential new therapies for acutely ill patients.”

CB-183,315 is a novel antibacterial agent discovered by Cubist scientists and the first agent Cubist has progressed to Phase 2 from its internal discovery efforts. The trial is a randomized, double-blind, active-controlled, dose-ranging study investigating the safety and relative efficacy of CB-183,315 to Vancocin® as the active comparator. The study will investigate dose regimens of 125mg of CB-183,315 administered twice daily and 250mg of CB-183,315 administered twice daily to 125 mg oral Vancocin administered four times a day over a period of 10 days.

Cubist's Chief Medical Officer Santosh Vetticaden, PhD, MD, said, "The unmet medical need we are attempting to address as we advance CB 183,315 in the clinic is daunting. CDAD rates and severity are increasing, due in part to the spread of a new strain of C. difficile with increased virulence for which current therapies are inadequate. We are excited about the possibility that CB-183,315 could potentially address this unmet medical need."

Cubist's Chief Scientific Officer Steve Gilman, PhD, said, "This is the first Phase 2 trial emanating from Cubist's internal research efforts and hence marks an important milestone as we continue to build a portfolio of potential new therapies for acutely ill patients."

Cubist Pharmaceuticals, Inc.