Amicus plots an end-of-year FDA filing for its resuscitated lead drug

Amicus Therapeutics ($FOLD), fresh off reviving a once-failed drug, has reached an accord with U.S. regulators and is on track to submit its rare disease treatment for FDA approval before the end of this year.

Based on feedback from the FDA at a prefiling meeting, Amicus is preparing an application for its drug to treat the rare genetic disorder Fabry disease. The agency has agreed to judge the drug, migalastat, on its ability to clear out the dangerous lipids that mark Fabry, looking at Amicus' already-completed clinical studies in its review.

Now the New Jersey biotech expects to finalize its U.S. application in the fourth quarter of this year, and the FDA has promised an accelerated review for migalastat, considering the drug's effect on surrogate endpoints to speed up the process but requiring Amicus to conduct postapproval studies to confirm its benefits to Fabry patients.

In Europe, migalastat is already under review through the EU's similar accelerated assessment program, and Amicus expects a final word by the end of 2015.

Migalastat's regulatory progress is a welcome change of pace for Amicus after the company watched its market value plummet in 2012 when the drug failed to beat placebo in a pivotal trial. That setback convinced partner GlaxoSmithKline ($GSK) to abandon the drug and appeared to signal the end for migalastat. But Amicus persevered, last year convincing the FDA to consider a different biomarker for improving Fabry symptoms and to evaluate migalastat solely in the roughly 30% to 50% of patients who carry a specific mutation.

Since then, the drug has been a clinical success, and Amicus' share value has increased nearly 10-fold since its 2014 nadir.

Migalastat, to be sold as Galafold, is designed to improve upon the standard-of-care enzyme-replacement therapies (ERTs) currently used to treat Fabry, which results from a deficiency of the enzyme alpha-galactosidase A and often leads to renal failure and death. In its Phase III program, Amicus' drug measured up to Sanofi's ($SNY) Fabrazyme and Shire's ($SHPG) Replagal in two measures of kidney function, a victory management heralded as evidence that patients can safely switch between the leading ERTs, which require biweekly infusions, and migalastat, which is a pill.

- read the statement (PDF)