Xifaxan 550mg, the first-and-only nonsystemic antibiotic approved for the treatment of IBS-D in adults, is a rifamycin antibacterial that acts by binding to the beta-subunit of bacterial DNA-dependent RNA polymerase blocking one of the steps in transcription, resulting in inhibition of bacterial protein synthesis. The FDA approval of Xifaxan was based on data from three double-blind, placebo-controlled clinical trials of over 3,000 adults; in the first two trials, 1,258 IBS-D patients were randomly assigned to receive Xifaxan or placebo for 14 days, followed by a 10-week treatment-free period. A greater number of patients treated with Xifaxan reported improvements in abdominal pain and stool consistency compared to placebo. In the third trial, 636 patients with recurrence were randomly assigned to receive Xifaxan or placebo for two additional 14-day courses separated by 10 weeks. More patients treated with Xifaxan were responders in abdominal pain and stool consistency vs. placebo in this study.
One Xifaxan 550mg tablet is to be taken orally three times a day for 14 days for IBS-D; patients who experience a recurrence of symptoms can be retreated up to two times with the same dosage regimen. A full course of Xifaxan 550mg for IBS-D is available in a convenient 2-week pack of 42 pills.
Xifaxan 550mg is also approved for the reduction in risk of overt hepatic encephalopathy recurrence in adults. Xifaxan 200mg is indicated for travelers’ diarrhea due to noninvasive E. coli.
For more information call (855) 543-3784 or visit FDA.gov.