Catalyst Pharmaceuticals Crashes 50% Following 'Refusal To File' Letter From FDA

Shares of Catalyst Pharmaceuticals Inc CPRX lost nearly half of its value Wednesday morning after the company disclosed it received a "Refusal to File" letter from the U.S. Food and Drug Administration.

The "Refusal to File" letter was sent to Catalyst Pharmaceuticals regarding its New Drug Application (NDA) for Firdapse, an investigational drug candidate for the symptomatic treatment of Lambert Eaton myasthenic syndrome (LEMS) and congenital myasthenic syndromes.

The FDA's letter stated that Catalyst Pharmaceuticals' application was not sufficiently complete and it is seeking additional supporting information. The letter did not comment on the acceptability of the submitted clinical data and no judgment is made in the letter.

"We expect to work closely with the FDA over the coming weeks in an effort to resolve the open issues and to define a path forward for a successful resubmission of our application at the earliest point in time," said Patrick J. McEnany, Chairman and CEO of Catalyst. "We remain focused on delivering on our promise to transform the way people living with LEMS and CMS are provided access to a safe and effective, FDA approved therapy. Additionally, our Expanded Access Program continues to enroll new patients and provide Firdapse at no cost to patients who meet the enrollment criteria."

The stock traded recently at $1.09, down 41 percent.