Catalyst soars as its controversial rare disease drug aces Phase III

Catalyst CEO Patrick McEnany

Catalyst Pharmaceutical Partners ($CPRX) is heralding positive late-stage results for its lead drug, planning to make its case to the FDA in hopes of winning approval for a much-scrutinized orphan treatment.

The drug, Firdapse, is designed to treat Lambert-Eaton myasthenic syndrome (LEMS), a rare neuromuscular disease that gradually robs patients of their mobility. In a Phase III trial on 38 LEMS sufferers, the treatment met its co-primary endpoints of improving physician-rated and patient-reported symptoms of the disease, Catalyst said, significantly beating out placebo while proving safe and well-tolerated.

Now Catalyst is requesting a pre-NDA meeting with the FDA, planning to kick off a rolling submission for Firdapse in early 2015. Last year, the biotech picked up the agency's coveted breakthrough-therapy designation for the drug, which promises to shorten its time under review.

The news sent the biotech up as much as 20% on Monday evening, reaching a 6-year high. And, if all goes according to plan, Firdapse would become the only FDA-approved treatment for LEMS.

However, whether that's entirely good news for LEMS patients has been the subject of some controversy. As TheStreet's Adam Feuerstein reported last year, a family-owned outfit called Jacobus Pharmaceuticals has been giving away doses of 3,4-Dap, a treatment similar to Firdapse, for more than 20 years. That drug has never secured FDA approval and thus can't be sold legally in the U.S. Firdapse, if approved, could thus demand an orphan price tag just to replace an effective treatment that's currently free, leading Jacobus to accuse Catalyst of disguising a business opportunity as an unmet medical need.

But Catalyst CEO Patrick McEnany contends that winning approval for and launching Firdapse will ultimately benefit the largest number of people. Jacobus' compassionate use system can't cover the entirety of LEMS patients--Catalyst wouldn't have been able to enroll a Phase III study if it could--and, unlike 3,4-Dap, his company's drug would have gone through the rigors of FDA review, he told Feuerstein in October 2013.

Furthermore, in announcing Firdapse's Phase III results, McEnany said the company is gearing up to launch an expanded access program of its own next month, providing its drug at no charge "to patients who meet the inclusion/exclusion requirements" until some time after approval.

BioMarin ($BMRN) has marketed the drug in Europe since 2009, and, in out-licensing Firdapse to Catalyst in 2012, took a $5 million stake in the biotech.

- read the results
- here's TheStreet's reporting on Jacobus