Pfizer sues Ranbaxy over Lipitor and Caduet patents

Pfizer has sued Ranbaxy Laboratories, claiming that the firm has infringed its patents over cholesterol drugs Lipitor (atorvastatin calcium) and Caduet (amlodipine and atorvastatin), it has emerged.

The company has filed these lawsuits in an attempt to prevent the sale of generic formulations of these drugs, Bloomberg reports.

It hopes to prevent the marketing of generic versions of these compound until the expiry of two patents on the process used to manufacture the drugs expires in 2016, according to the lawsuits filed in cases numbered 08cv164 and 08cv162 at the US district court in Wilmington, Delaware.

Senior vice-president of global intellectual property at Ranbaxy Laboratories said the firm has no comment on the lawsuits.

Last week, the federal court of appeal in Canada upheld the enantiomer (calcium salt) Canadian Patent No 2,021,546 which expires in July 2010, reversing a lower court ruling that this patent could not block Ranbaxy Laboratories from obtaining approval for competing product to Lipitor.

Pfizer hailed the decision as important for patients as well as the firm, claiming it sends a strong message regarding the importance of protecting intellectual property in Canada.

It added that the decision acts as an incentive for research-driven firms to make high-risk investments in the development of novel medications to save lives.