WASHINGTON (AP) -- Shares of specialty drugmaker Amarin tumbled Friday after the Food and Drug Administration suggested it may need more data to approve a new use for the company's prescription fish-oil drug.
THE SPARK: The Food and Drug Administration posted its review of the company's request to expand approval of Vascepa, a form of fish oil designed to lower triglycerides, a type of fat in the bloodstream.
While the FDA notes that Vascepa lowered patients' triglyceride levels by more than 20 percent, the agency's scientists also questioned whether that will translate into a real health benefits for patients.
The reviewers pointed to several recent studies in which reducing triglycerides and other cholesterol targets didn't actually reduce the rate of heart attack and related problems. Amarin is studying the cardiovascular impact of Vascapa in a trial called REDUCE-IT, but results will not be available for several years. The FDA's review suggested approval of the drug's new indication may need to wait until the findings can be reviewed.
The agency will ask a panel of experts to vote on whether to recommend approval of the drug at a meeting next Wednesday.
THE BIG PICTURE: The FDA first approved Vascepa in July 2012 for patients with unusually high triglycerides.
Amarin is now seeking expanded approval for patients with high triglyceride levels and heart disease who are already taking a statin drug to try and control their cholesterol. The agency is expected to issue a decision on the drug by Dec. 20.
But FDA regulators seem to be cautious about expanding the drug's approval without more evidence of its heart benefits.
In 2011, a large government study called into question the benefits of a similar triglyceride-lowering drug marketed by Abbott Laboratories. In the 5,000-patient study, people with diabetes taking Abbott's Trilipix plus a statin had just as many heart attacks as people taking a statin alone.
In the documents posted online Friday, the FDA says panelists should consider such research "when opining whether to recommend expanding the treatment indication for Vascepa prior to confirming its cardiovascular benefit."
The FDA is not required to follow the recommendations of its advisory panels, though it often does.
SHARE ACTION: Shares of Amarin Corp. plc fell $1.28, or 20 percent, to close Friday trading at $5.09. The stock touched $5.01, its lowest point since November 2010, during the session.