Oct. 4, 2010 (Business Wire) -- Salix Pharmaceuticals, Ltd. (NASDAQ:SLXP) today announced that the FDA has extended the Prescription Drug User Fee Act (PDUFA) goal date for the Agency’s Priority Review of the efficacy supplement to NDA 21-361 for XIFAXAN® (rifaximin) 550 mg Tablets for the proposed indication of the treatment of non-constipation irritable bowel syndrome (Non-C IBS) and IBS-related bloating. The FDA has notified Salix that it requires additional time for review of the application and has extended the December 7, 2010 goal date by three months. The extended user fee goal date is March 7, 2011.
“The extension of the PDUFA goal date is not unexpected, given the Agency’s historical management of Priority Reviews,” stated Bill Forbes, Pharm.D., Executive Vice President and Chief Development Officer, Salix Pharmaceuticals. “We are encouraged by the productive interactions we continue to have with the Agency during the review and believe it is unlikely that there will be an advisory committee meeting for this submission. We look forward to the completion of the review by the new goal date.”
XIFAXAN® (rifaximin) 550 mg tablets
Important Safety Information
XIFAXAN 550 mg is indicated for reduction in risk of overt hepatic encephalopathy (HE) recurrence in patients = 18 years of age. In the trials of XIFAXAN for HE, 91 percent of the patients were using lactulose concomitantly. XIFAXAN has not been studied in patients with MELD scores > 25, and only 8.6 percent of patients in the controlled trial had MELD scores over 19. There is increased systemic exposure in patients with more severe hepatic dysfunction. Therefore, caution should be exercised when administering XIFAXAN to patients with severe hepatic impairment (Child-Pugh C).
XIFAXAN is contraindicated in patients with a hypersensitivity to rifaximin, any of the rifamycin antimicrobial agents, or any of the components in XIFAXAN. Hypersensitivity reactions have included exfoliative dermatitis, angioneurotic edema, and anaphylaxis.
Clostridium difficile-associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including XIFAXAN, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon which may lead to overgrowth of C. difficile. If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued.
The most common adverse reactions occurring in >8 percent of patients in the clinical study were edema peripheral (15 percent), nausea (14 percent), dizziness (13 percent), fatigue (12 percent), ascites (11 percent), muscle spasms (9 percent), pruritus (9 percent), and abdominal pain (9 percent).