Positive results from Cubist CXA-201 and CB-183,315 Phase 2 studies for complicated intra-abdominal infections

Cubist Pharmaceuticals, Inc. (NASDAQ: CBST), a leading acute care therapeutics company, today announced positive top-line results from the recently completed Phase 2 studies of its CXA-201 and CB-183,315 antibiotic pipeline candidates. CXA-201 was studied for the treatment of complicated intra-abdominal infections (cIAI) in adults. Based on these latest top-line data, as well as data observed in previous studies, the company plans to initiate Phase 3 studies with CXA-201 for indications in both cIAI and complicated urinary tract infections (cUTI) by year-end 2011. CB-183,315 was studied for the treatment of a severe and sometimes life-threatening diarrhea caused by Clostridium difficile known as C. difficile-associated diarrhea, or CDAD. The company remains on track to make a formal decision of whether to initiate Phase 3 studies with CB-183,315 by year-end 2011.

“There is a large and growing need for new and better antibiotics across the globe, and we are very pleased with these positive results.”

"Positive results from these two Phase 2 clinical trials are significant milestones for our pipeline, as well as our ongoing efforts to become a global acute care leader," said Steven Gilman, Ph.D., Executive Vice President of Research and Development. "There is a large and growing need for new and better antibiotics across the globe, and we are very pleased with these positive results."