FDA revokes approval for Sun Pharma 's seizure drug over compliance issues

The company said in June it had been working "very aggressively" to find partners for the product. It had had "some advanced discussions" and aimed to launch the drug by the second half of fiscal 2016.

Analysts estimated modest sales of about $50 million annually from Elepsia XR.

SPARC had said it would produce the drug at Sun Pharma's Halol plant, in the western Indian state of Gujarat, as an adjunct treatment for partial onset seizures in epilepsy patients of 12 years and older.

Most analysts saw the approval as positive mainly because it came despite the FDA having expressed concerns a year ago about manufacturing processes at the Halol plant.

Sun Pharma had been working on fixing the issues the FDA outlined and some analysts said the approval allayed fears of a possible adverse FDA action at Halol.

On Saturday, SPARC said the FDA issued it a "Complete Response Letter" in which it said "the compliance status of the manufacturing facility was not acceptable on the date of approval".

It said Sun Pharma "has taken several corrective measures" to fix problems at the plant.

(Reporting by Zeba Siddiqui; Editing by Paul Tait)