Pfizer sues Dr Reddy's over Lipitor

Pfizer is suing India's Dr Reddy's Laboratories in a Delaware federal court over a proposed generic version of the blockbuster cholesterol med Lipitor, according to Livemint. Dr Reddy's notified Pfizer in October that it was seeking FDA approval for a generic version of the drug. The last-to-expire patent covering the drug enjoys pediatric exclusivity through January 2017.

Pfizer acknowledged Dr Reddy's October ANDA filing in its Q3 statement. "Dr Reddy's asserts the invalidity and/or non-infringement of three patents for Lipitor which, including the six-month pediatric exclusivity period, expire between 2013 and 2017. Dr. Reddy's is not challenging our enantiomer patent which, including the six-month pediatric exclusivity period, expires in June 2011," according to the statement.

Lipitor continues to be a top-seller for Pfizer, which in 2008 fought off Ranbaxy's attempt to bring a copycat version to market. However, the company has seen Lipitor's sales decline. During the first nine months of the year, Lipitor had worldwide sales of roughly $8.3 billion-down from $9.3 billion during the same period 2008. This represents a decline of approximately 11 percent, according to the company's quarterly earnings statement.

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