Salix Pharmaceuticals, a subsidiary of Bausch Health, has emerged victorious in its ongoing legal battle to protect its medication Xifaxan, used to treat irritable bowel syndrome with diarrhea (IBD-D), from its competition. The latest development recently took place when the U.S. District Court for the District of Columbia rejected Norwich Pharmaceuticals’ attempt to compel the FDA to approve its proposed generic version of Xifaxan.
In a previous legal showdown in Delaware, it was determined that Norwich’s generic version would infringe on three of Salix’s patents related to Xifaxan’s indication for hepatic encephalopathy (HE). As a result, the court ruled that Norwich could not launch its generic until these patents expire in 2029. Additionally, the court found certain Xifaxan patents related to the IBD-D use to be invalid. In response, Norwich removed the HE indication from its generic label and sought FDA approval for a “skinny label” solely for the treatment of IBD-D.
The FDA provided tentative approval for the generic but withheld final approval until 2029, effectively preventing the drug’s immediate launch. Norwich contested the FDA’s decision, leading to the recent ruling by the D.C. court in favor of the FDA and Salix.
Alvogen, the parent company of Norwich, expressed disappointment with the court’s decision and is considering the possibility of an appeal. Andrea Sweet, Alvogen’s chief legal officer, stated that they are confident that the Federal Circuit will confirm the invalidity of the IBS-D and polymorph patents, ultimately allowing the FDA to approve Norwich’s application for IBS-D treatment without further delay.
On the other hand, Bausch Health expressed satisfaction with the court’s decision. Salix is awaiting a decision on its appeal regarding the court’s earlier decision to invalidate some of its patents. This decision is expected to be delivered in the first quarter of 2024.
Salix has taken steps to protect Xifaxan from generic competition by striking deals with Actavis, Novartis’ Sandoz, and Sun Pharma, ensuring that their generics will not enter the market until 2028. Xifaxan has been a cornerstone medication for Bausch Health, contributing significantly to Salix’s 13% growth rate in the third quarter of the current year.
Salix Pharmaceuticals has been victorious by defending its patent rights for Xifaxan against competitors. The courts have upheld Salix’s patents related to hepatic encephalopathy (HE) and affirmed the invalidity of certain patents for the treatment of irritable bowel syndrome with diarrhea (IBD-D). The legal battle is not over, as Alvogen is considering an appeal, and Salix awaits a decision on its patent dispute. The outcome of this legal dispute has significant implications for the pharmaceutical industry and the availability of affordable generic medications for patients.
