According to several news reports, Dr.Reddy’s Labs (DRL) has been sued by AbbVie Inc. and Wisconsin Alumni Research Foundation in the US District Court of Delaware for infringement of three patents on the drug Zemplar (Paricalcitol) and its injectable forms. The drug is used to treat secondary hyper-parathyroidism associated with chronic renal failure.
In May 2013, DRL informed AbbVie of the filing of its Abbreviated New Drug Application (ANDA) for injectable forms of Zemplar. In the same letter, DRL also stated, inter alia, its opinion that the three patents were invalid. Predictably, AbbVie has taken the position that filing of the ANDA application prior to the expiry of the three patents is an act of infringement.