said Wednesday that the Food and Drug Administration had rejected its application to market the antidepressant Lexapro for treating social anxiety disorder.
Lexapro, which is Forest's bestselling drug, is approved for the initial treatment and maintenance treatment of major depressive disorder and for generalized anxiety disorder in adults. For the three months ended Dec. 31, Lexapro produced sales of $427 million, or 54% of corporate revenue.
Although federal law allows doctors to prescribe an FDA-approved drug for any use, companies can market the drug only for specific indications endorsed by the FDA. That's why companies seek FDA approval for multiple uses for a single drug.
This is the second setback for Lexapro in four weeks. The FDA also rejected Forest's application to have the drug marketed for treating panic disorder, which is characterized by recurrent panic attacks. Social anxiety disorder, also known as social phobia, refers to an extreme fear of embarrassment in social situations.
In regular trading Wednesday, Forest's stock closed at $37.05, up 30 cents. But in after-hours trading, the stock was down 76 cents.
Forest says it's "not approvable letter" from the FDA noted that although one of two clinical trials supported the application, the FDA "raised questions related to the reliability of patient data at one study center in the second pivotal study."
Once the FDA eliminated data from the one study center, test results failed to achieve statistical significance. Forest says it is reviewing the FDA's analysis "and will determine the appropriate next steps ... in the coming months."