Rifaximin (Xifaxan) antibiotic can be useful in treating bowel disease symptoms including that of irritable bowel syndrome, according to Salix Pharmaceuticals.
Phase 3 clinical trials evaluating the efficacy and tolerability of Rifaximin (Xifaxan) 550 mg data from 1,260 patients with non–constipation irritable bowel syndrome (IBS) showed that a 14–day course of Xifaxan 550 mg, taken 3 times daily, achieved adequate relief of IBS symptoms in a significantly greater proportion of patients during the first 4 weeks following 2 weeks of treatment.
Rifaximin is a gut–selective antibiotic with negligible systemic absorption and broad–spectrum activity in vitro against both Gram–positive and Gram–negative pathogens.
Rifaximin tablets 200 mg, which Salix markets in the United States under the trade name Xifaxan (rifaximin) tablets 200 mg, currently is approved for the treatment of patients, 12 years of age or older, with travelers’ diarrhea (TD) caused by non–invasive strains of Escherichia coli.
Rifaximin has been used in Italy for 24 years and is approved in 33 countries. Salix acquired rights to market rifaximin in North America from Alfa Wassermann S.p.A. in Bologna, Italy. Alfa Wassermann markets rifaximin in Italy under the trade name Normix.
Non–constipation IBS patients received Xifaxan 550 mg or placebo three times daily for 14 days (2 weeks) and were then followed for an additional 10 weeks.
A significantly greater proportion of patients achieved adequate relief of IBS symptoms within the first month, with continued relief during the first 2 months and during the entire 3 months in both studies, compared with placebo.
Rifaximin (Xifaxan) 550 mg significantly improved the global assessment of IBS symptoms as well as the IBS specific symptoms of bloating, stool consistency and abdominal pain and discomfort during weeks 3–6 and during the entire 3 months in both studies.
“These data, which clearly demonstrate rifaximin’s ability to provide durable relief of IBS symptoms and bloating, represent a major milestone in our efforts to bring new and meaningful hope to patients with IBS,” stated Mark Pimentel, M.D., Gastrointestinal Motility Program director at Cedars–Sinai Medical Center and principal investigator of the clinical trials.
Salix is planning to submit the rifaximin non–C IBS New Drug Application by the end of June 2010.
Rifaximin branded as Xifaxan has been recommended for approval to treat hepatic encephalopathy in US, Salix Pharmaceuticals, Ltd announced.
In February, the Gastrointestinal Drugs Advisory Committee of US FDA recommended by a vote of 14 to 4 in favor of the approval of rifaximin (Xifaxan) tablets, 550 mg for the maintenance of remission of hepatic encephalopathy (HE).
The study demonstrated a statistically significant and clinically meaningful reduction in the risk of recurrent overt hepatic encephalopathy.
The risks of experiencing a breakthrough overt hepatic encephalopathy episode and hospitalizations were reduced by over 50 percent in Xifaxan 550 mg-treated subjects.
Irritable bowel syndrome (IBS) includes altered bowel habits with bloating, abdominal pain and discomfort. Among other contributors, recent science has shown that alterations in gut flora/bacteria have been identified as a potentially important contributor to the pathophysiology of IBS. Small intestinal bacterial overgrowth, a condition associated with excessive numbers of bacteria in the small intestine, may underlie some of the gastrointestinal symptoms associated with IBS. The Company now estimates the U.S. commercial opportunity represented by the non–constipation IBS market to be approximately $7 billion in peak year.
Irritable bowel syndrome (IBS) affects approximately 15 percent of adults in the United States.
Salix Pharmaceuticals, Ltd., headquartered in Raleigh, NC, develops and markets prescription pharmaceutical products for the treatment of gastrointestinal diseases. Salix’s strategy is to in–license late–stage or marketed proprietary therapeutic drugs, complete with any required development and regulatory submission of these products, and market them through the Company’s gastroenterology specialty sales and marketing team.
Salix also markets Moviprep (PEG 3350, sodium sulfate, sodium chloride, potassium chloride, sodium ascorbate and ascorbic acid for oral solution), Osmoprep (sodium phosphate monobasic monohydrate, USP and sodium phosphate dibasic anhydrous, USP) Tablets, Visicol (sodium phosphate monobasic monohydrate, USP, and sodium phosphate dibasic anhydrous, USP) Tablets, Apriso (mesalamine) extended–release capsules 0.375 g., Metozolv ODT (metoclopramide HCl), Pepcid (famotidine) for Oral Suspension, Oral Suspension Diuril (Chlorothiazide), Aza san Azathioprine Tablets etc.