The pending litigation between Teva Pharmaceutical Industries Ltd and Pfizer over Celebrex has reached a settlement. In the agreement, Teva would be able to produce and sell a generic version of Celebrex, Pfizer's flagship pain medication starting December of this year.

The settlement comes one month after a US federal court threw out the patent claimed by Pfizer over the formulation of the drug. With this, other drug firms, such as the Israeli based Teva would be allowed to manufacture cheaper versions of the said drug. The patent was said to be valid until May 30 of this year. This decision was hailed by one of the defendant firms, Mylan as 'favorable' and the company would push through with its plans to sell a generic version of the drug.

In the decision of the federal court, it had denied the claim of Pfizer that the existing patent allowed another 18 months of exclusivity for the company in the sale and manufacture of the drug in the United States. Originally, Pfizer had filed a number of infringement of patent lawsuits against Teva, Mylan Inc and four other generics drug firms. 

A spokesperson for Pfizer confirmed that included in the settlement agreement with Teva is a license to allow a launch of the generic version of the drug. Furthermore, the agreement would allow, under specific circumstances, royalty earnings to be provided for the remainder of the term of the patent, which formally ends on December 2, 2015. Other terms were deemed confidential, according to the statement read by the Pfizer representative.

The Pfizer spokesperson did confirm that Pfizer "will continue its defense of the patent, which it believes is valid and was properly granted by the Patent Office, and will pursue all appropriate remedies for infringement."

Three of the six generic drug manufacturers named in the suit, namely Teva, Mylan and Actavis PLC had already received initial FDA approval for the manufacture and sale of the generic versions of Celebrex starting May of 2014.