Two DIFICID Phase 3 trial data in C. difficile infection presented at AGS Annual Meeting

Optimer Pharmaceuticals (NASDAQ: OPTR) today announced the presentation of an additional analysis of data from the company's two Phase 3 clinical trials of DIFICID™ (fidaxomicin), an investigational antibiotic for the treatment of Clostridium difficile Infection (CDI), at the American Geriatric Society (AGS) Annual Meeting held in National Harbor, Maryland.

The analysis showed that above 40 years, advancing age was associated with decreasing odds of sustained cure, a more prolonged time to resolution of diarrhea and an increased risk of disease recurrence, independent of treatment with DIFICID or vancomycin. In addition, treatment with fidaxomicin was associated with a 54% lower risk of recurrence (p< 0.001) and a 1.9-fold greater probability of cure without recurrence (p< 0.001) in comparison to vancomycin. In the per protocol population, 999 patients treated with either DIFICID or oral vancomycin from the two DIFICID Phase 3 trials were divided into age groups defined by decades. By regression modeling, researchers determined that advancing age for each decade above the age of 40 was associated with a 17% reduction in probability of CDI cure (odds ratio or OR 0.83)

"With more than two-thirds of hospitalized patients with CDI in the U.S. being over the age of 65, advancing age has long been known as a risk factor for CDI, disease relapse and CDI-related mortality," said Thomas Louie, M.D., Professor of Medicine, Department of Medicine and Microbiology-Infectious Diseases at the University of Calgary. "This study suggests that increased risk doesn't simply start when a person turns 65. Instead, the risk gradually increases with age. With the backdrop of an aging population and widespread use of antibiotics, this progressive deterioration of CDI outcomes with age is a particularly significant public health concern."