Optimer presents two fidaxomicin Phase 3 trials data for CDI infection at IDSA Annual Meeting

Optimer Pharmaceuticals, Inc. (Nasdaq: OPTR) announced today the presentation of combined data from its two fidaxomicin Phase 3 trials in patients with Clostridium difficile infection (CDI) at the 48th Annual Meeting of the Infectious Disease Society of America (IDSA) in Vancouver, British Columbia, Canada.  During an oral presentation, investigator Derrick Crook, M.D., of the University of Oxford, presented combined data showing that CDI patients treated with fidaxomicin experienced 47% fewer recurrences than patients treated with vancomycin.

Dr. Crook presented combined data from the two Phase 3 trials showing cure rates, recurrence rates and global cure rates for the intent to treat (ITT) population.  The recurrence rates were 13% for the fidaxomicin arm compared to 24% for the vancomycin arm (p < 0.001). Global cure rates were 75% for fidaxomicin compared to 63% for vancomycin (p < 0.001). Cure rates were similar for both fidaxomicin and vancomycin (88% vs. 86%).  Fidaxomicin was well-tolerated in both studies.  

The combined results for the per protocol and modified intent to treat populations are shown in the table below:  

"The combined data set of more than 1,100 patients show that fidaxomicin is statistically superior in preventing recurrences and achieving global cures compared to vancomycin.  Fidaxomicin as a single agent offers potential advantages over existing therapies," said Dr. Crook, Consultant Microbiology/Infectious Diseases and Professor of Infectious Diseases and Microbiology, Experimental Medicine Division, Nuffield Department of Clinical Medicine (NDM), University of Oxford.  

For a complete list of abstracts, please visit the Resources page on our website: www.optimerpharma.com

Fidaxomicin Clinical Studies

The two fidaxomicin Phase 3 clinical studies were multi-center, randomized, double-blind trials, which enrolled a total of 1,164 adult subjects.  Subjects with confirmed CDI received either fidaxomicin (200 mg q12h) or Vancocin® (125 mg q6h), the only FDA approved product for the treatment of CDI. These studies were designed to evaluate safety and compare the response to treatment in subjects during and after a 10-day course of therapy. The primary endpoint was non-inferiority compared to Vancocin in clinical cure (defined as patients requiring no further CDI therapy two days after completion of study medication.  If cured, subjects were monitored for a subsequent four-week period to evaluate recurrence, which was a secondary endpoint.  Global cure, also a secondary endpoint, was defined as patients who were cured and did not have a recurrence during this subsequent four-week period. In both of these studies, fidaxomicin achieved its primary endpoint of non-inferiority compared to Vancocin.  Fidaxomicin was also statistically superior to Vancocin in recurrence rate, reducing CDI recurrences by 47% and in global cure rate. Fidaxomicin was well tolerated in both studies.