Friday, March 16, 2007

Pfizer sued Ranbaxy over Caduet Patent

Ranbaxy has yet again made Pfizer to defend their patents for blockbuster drug products now adding anti-cholesterol drug Caduet in their ongoing list of patent litigations. Pfizer filed a patent infringement suit against Ranbaxy in response to Ranbaxy’s ANDA submission with the US FDA for marketing approval of generic Caduet before expiry of Orange Book listed patents. Caduet is combination of amlodipine besylate and atorvastatin calcium. In its complaint, Pfizer alleged that Ranbaxy’s ANDA products would infringe Pfizer’s patents for Caduet. However, Ranbaxy is believed to have first-to-file status for Caduet.


  1. Dear Varun,
    Nice one.
    Can you give some analysis on this case? I would like to know that
    1) For which patents Ranbaxy applied for Para IV and for which patents Pfizer sued Ranbaxy.
    2) As Atorvastatin patents are valid in earlier case, Why Ranbaxy applied for Para IV?
    Looking for your comment.

  2. Ranbaxy filed Para IV certification with respect to all Orange Book patents for Caduet.

    However, Pfizer sued ranbaxy for infringement of the U.S. Patents Nos. 4,681,893 and 6,455,574.

    Pfizer in its complaint has raised the issue of res judicta and collateral estoppel from attacking the validity and enforceability of the patent term extension for the '893 patent and the infringement, validity and enforceability of the '893 patent (as it is already decided by district and Appeal court).