FDA posts 5-HT4 receptor agonist briefing documents

FDA posted briefing documents ahead of the agency's Gastrointestinal Drugs Advisory Committee meeting on Thursday to discuss cardiovascular safety programs for serotonin (5-HT4) receptor agonists in development for GI indications. FDA will ask the panel whether a dedicated CV safety trial should be required to demonstrate the safety of 5-HT4 agonists, and if so, should the trial be conducted before or after approval.

There are two 5-HT4 agonists in active clinical development in the U.S. for GI indications. Velusetrag ( TD-5108) and TD-8954 from Theravance Inc. (NASDAQ:THRX) have completed Phase II testing for chronic constipation and Phase I testing in healthy volunteers, respectively. A third product, constipation therapy naronapride from ARYx Therapeutics Inc. (Pink:ARYX), has completed a Phase IIb trial. However, the company said in March that it would wind down operations after FDA delayed responding to its request for an SPA for Phase III testing. Theravance was up $0.40 to $23.40 on Tuesday. ...