Japanese firms sue Lupin in US court over eye drug

Japan’s Senju Pharmaceutical and Kyorin Pharmaceutical along with US-based Allergan have sued Lupin alleging violation by the Indian firm in case of 0.3 per cent

Gatifloxacin ophthalmic

solution.

Crucial patents for Gatifloxacin, a synthetic broad-spectrum antibiotic, are held by the Japanese firms. Allergan produces an eye-drop formulation called Zymar, based on the same antibiotic being the exclusive licensee for eye applications.

In a court case filed last week in the District Court of Delaware, the firms have submitted that in the first week of April Lupin had filed for a drug master file for gatifloxacin. Then, Lupin or entities controlled by it had also submitted a generic drug application to the USFDA for approval to market a glatifloxacin ophthalmic solution with 0.3 per cent strength.

The firms have alleged that Lupin’s application is in infringement of US Patent Numbers 6,333,045 (Aqueous Liquid Pharmaceutical Composition Comprised of Gatifloxacin, issued December 25, 2001) and 5,880,283 (8-Alkoxyquinolonecarboxylic Acid Hydrate With Excellent Stability and Process for Producing the Same, issued March 9, 1999). The world-wide ophthalmology drugs market is expected to reach a size of $19.8 billion by the year 2014 growing at a CAGR of 4 per cent from 2009-2014. The US ophthalmic drug market has crossed $5 billion in 2008.

Lupin has filed a paragraph-IV application for the product, which means it intends to market its approved product before expiration of two important patents, the firms said in their court document that have been accessed by

Financial Chronicle.

The two patents in question expire during 2016 and 2020. The USFDA approved Zymar in 2003 for the treatment of bacterial conjunctivitis.