MUMBAI: A legal battle between US pharma giant Pfizer and Indian company Sun Pharmaceutical has escalated, with the world’s largest maker of
medicines alleging in court filings that in addition to the original patent that it claims Sun violated, it infringed another patent when it sought approval for its generic version of Lyrica, a blockbuster drug used to treat seizures. In a case filed in the US District Court for the District of Delaware on May 3, 2009, Pfizer had alleged that Sun infringed on a patent that Pfizer and Northwestern University held. Last week, the company charged Sun with violating another patent for Lyrica. Incidentally, Pfizer will lose patent protection for this drug only in 2018. Lyrica (pregabalin) is used for treating pain caused by neurological diseases such as postherpetic neuralgia as well as seizures. Lyrica currently ranks third in the anti-seizure market, and is estimated to have global sales of approximately $1.2 billion. The drug’s sales jumped 45% in 2008 to $675 million, offsetting Pfizer’s losses from its blockbuster drug Lipitor. Lyrica may become Pfizer’s leading product by 2012. The pharma giant, in its filing, said it had received a letter from Sun Pharma informing that Sun’s abbreviated new drug application (ANDA) contained a claim that the “175 patent was invalid, unenforceable, and not infringed by Sun’s proposed product”. Pfizer is seeking an injunction that would bar Sun from marketing and manufacturing generic versions of Lyrica (pregabalin) prior to patent expiration as well as monetary relief, if Sun were to sell its generic product, and fees and costs.” When contacted, a Sun Pharma spokesperson said: “We don’t comment on our product pipeline or the associated litigation.” Indian pharma majors Lupin and Wockhardt have also been taken to court by Pfizer for infringement of other patents related to the same drug. Teva, Sandoz, Actavis, Cobalt Laboratories, Alphapharm are some of the other generic companies that Pfizer is in litigation with over Lyrica.