said Wednesday that a federal court judge upheld the validity of a patent for the main ingredient in Norvasc, the drugmaker's second best-selling product and the world's most-prescribed blood pressure medication.
The ruling by a judge in Illinois blocked an attempt by the Canadian generic-drug maker
to sell a generic version of Norvasc in the U.S. before September 2007.
Norvasc contributed $3.46 billion, or 9% of corporate sales, to Pfizer's top line for the nine months ended Sept. 30, trailing only the cholesterol drug Lipitor, which produced sales of $8.83 billion.
Lipitor itself survived a challenge last month when a federal judge in Delaware ruled against India-based generic-drug company
claim that two Lipitor patents were invalid or unenforceable. Ranbaxy says it will appeal. In the Norvasc case, there was no immediate comment from Apotex.
"We are gratified that the court has affirmed the validity of our Norvasc patent," said Jeffrey Kindler, vice chairman and general counsel of Pfizer, in a prepared statement. "And we will continue to defend against any and all patent challenges that seek to undermine our mission of finding new therapeutic options for the patients we serve."
Pfizer said other generic-drug companies are trying to invalidate two Norvasc patents in the U.S., adding that the "those challenges are expected to be heard later this year."
Shares of Pfizer were lately down 37 cents, or 1.5%, to $23.91.