Impax remains upbeat after NDA rejection

Impax Pharmaceuticals says it remains confident of resolving issues at its manufacturing facilities following the rejection of its Parkinson’s drug Rytary.

The statement comes after the US Food and Drug Administration (FDA) rejected Impax’s NDA for Rytary citing unresolved problems at the company’s manufacturing facility in Hayward, CA described previously in a warning letter.

The FDA warning from May 2011 (view it here) identified various violations of cGMP at Hayward which still need to be addressed before approval of Rytary can be made. These included problems relating to sampling and in-process materials in both testing procedures, as well as issues in the review process for investigating production failure.

Though Impax had withdrawn the site as a commercial producer of the drug during the NDA assessment, Hayward had been involved with the development of Rytary as well as various manufacture and distribution processes and thus a satisfactory re-inspection of the plant has been demanded.

In an official statement, Impax President and CEO Dr. Larry Hsu stressed his determination to succeed in the Rytary application by continuing to work with the FDA. “We remain committed to resolving the warning letter and bringing this new treatment option to patients who are suffering from Parkinson’s disease.”

‘Impax’ on the stockmarket

Following the FDA’s rejection, share prices for Impax fell as much as ten percent. In the past twelve months the company has fallen 2.4 percent and analysts can only speculate on Impax’s financial health before the announcement of its 2012 financial results in February.

Rytary is deemed to be an approvable drug but analysts are wondering how long the process is going to take before the FDA nods its head. Speaking with Reuters, financial analyst Corey Davis believed there could be a delay of a year on Rytary’s approval and cut his target price on Impax’s stock from $21 to $18.

Leerink Swann analyst Jason Gerberry noted to clients that Impax would take up to six months to satisfy the FDA but was overall positive: “Hayward issues are resolvable and we expect Rytary to eventually get approved," adding that if all is well at the next approval attempt the drug may be commercially available by 2014.

Rytary and GSK

Rytary is an extended-release capsule formulation for the treatment of Parkinson’s disease developed by Impax who will, on FDA approval, market and sell the drug within the US and Taiwan. For the rest of the world the rights are owned by GlaxoSmithKline.

GlaxoSmithKline declined to comment on the NDA dismissal but a spokesman did tell In-Pharmatechnologist.com that Rytary “hasn’t been filed in Europe.”