Ranbaxy Laboratories on Friday said that its US arm has received a notice from Actavis Inc (formerly Watson Laboratories) challenging the patent of acne treatment drug Absorica. The drug had been developed by Ontario-based Cipher Pharma and was licensed to Ranbaxy for promotion in the US .
Absorica is currently protected by two FDA patents expiring in September 2021. The Ranbaxy stock on Friday closed down 5% to R333.45 on the Bombay Stock Exchange.
For Ranbaxy, Absorica is a low-risk, high-margin drug with limited competition. The drug generated sales of $25 million in Q2 and enjoys 14% market share.
It is also important for Ranbaxy in the US, where it is already on the backfoot following import alerts on three of its Indian units, a 483 on Ohm Labs — its only US supplying plant — and increasing uncertainty on approval of its key drugs like Diovan and Valcyte generic.
"Ranbaxy Laboratories Inc, the wholly-owned subsidiary of the company, has received a Paragraph IV certification notice of filing from Watson Laboratories Inc of an abbreviated new drug application (ANDA) to the US Food and Drug Administration (USFDA) for a generic version of Absorica," the company said in a statement.
As per regulatory norms in the US, a generic firm can file an abbreviated new drug application (ANDA) challenging patent of drug under Paragraph IV certification, which, if successful, gives the challenger 180 days of marketing exclusivity to market the generic drug.
After the Para IV notice, the branded company has 45 days to file a patent-infringement action against the generic company. Once the suit has been filed, the FDA cannot approve the application till the generic company successfully defends the suit, or till 30 months are over, whichever is first.
"Ranbaxy Laboratories Inc and Cipher intend to vigorously defend Absorica's intellectual property rights and pursue all available legal and regulatory pathways in defence of the product," Ranbaxy said.
Absorica was approved by the FDA in May 2012, and Ranbaxy was granted a three-year marketing exclusivity period for it, which expires in May 2015. Watson’s entry is expected by April 2016, after which earnings from this drug will