Barr unit challenges Otsuka's patent on schizophrenia drug

March 20 (Reuters) - Barr Pharmaceuticals Inc. BRL.N said its Barr Laboratories Inc. unit has challenged Otsuka Pharmaceutical Co. Ltd.'s patent on schizophrenia drug ABILIFY.

On Monday, Otsuka had said it filed a suit in a U.S. federal court to prevent Barr from proceeding with the generic version of the drug.

(Reporting by Hari Kumar in Bangalore)

((Editing by Anil Kumar; Reuters Messaging: hari.kumar.reuters.com@reuters.net; within U.S. +1 646 223 8780; outside U.S. +91 80 4135 5800 )) Keywords: BARR PATENT/OTSUKA

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