Allergan plc, a leading global pharmaceutical company, confirmed that it has filed an Abbreviated New Drug Application (ANDA) with the US Food and Drug Administration (FDA) seeking approval to market Carbidopa and Levodopa extended-release capsules, 61.25 mg/245 mg, 23.75 mg/95 mg, 36.25 mg/145 mg and 48.75 mg/195 mg.

Allergan's ANDA product is a generic version of Impax Laboratories' Rytary, which is indicated for the treatment of Parkinson's disease, post-encephalitic parkinsonism, and parkinsonism that may follow carbon monoxide intoxication or manganese intoxication.

Impax Laboratories, Inc. filed suit against Allergan on August 17, 2015 in the US District Court for the District of New Jersey seeking to prevent Allergan from commercialising its ANDA product prior to the expiration of certain US patents. The lawsuit was filed under the provisions of the Hatch-Waxman Act, resulting in a stay of final FDA approval of Allergan's ANDA for up to 30 months from the date the plaintiffs received notice of Allergan's ANDA filing or until final resolution of the matter before the court, whichever occurs sooner, subject to any other exclusivities.

Based on available information, Allergan believes it may be a "first applicant" to file an ANDA for the generic version of Rytary and, should its ANDA be approved, may be entitled to 180 days of generic market exclusivity.

For the 12 months ending July 31, 2015, Rytary had total US sales of approximately $15 million, according to IMS Health data.