(Reuters) - A U.S. appeals court ruled on Monday that a patent on Takeda Pharmaceutical Co Ltd's cancer treatment Velcade is valid, pushing back the date when generic drug makers including Teva Pharmaceutical Industries Ltd and Mylan NV will be allowed to launch lower-cost versions of the drug in the United States.
The U.S. Court of Appeals for the Federal Circuit rejected arguments by a dozen generic drug companies that the Velcade patent was obvious and should not have been granted. The ruling, which reversed a lower court, will allow Takeda to sell Velcade exclusively until the patent expires in 2022.
The generic companies had moved to invalidate the patents after Takeda sued them for patent infringement.
Amy Atwood, a spokesman for Takeda, said the company was pleased with the decision.
Velcade is used to treat multiple myeloma, a type of blood cancer. The drug had $1.13 billion in U.S. sales last year.
Velcade is marketed by Johnson & Johnson outside the U.S.
Generic drug companies including Teva, Mylan and Novartis AG unit Sandoz have applied to make generic Velcade, prompting lawsuits from Takeda.
According to Takeda, the generic versions would infringe a patent issued in 2004 on a more stable form of Velcade's active ingredient. Takeda does not actually hold that patent, as the company asked the National Cancer Institute to help develop the compound. The patent was issued to the NCI, which exclusively licensed it to Takeda.
A U.S. judge in Delaware ruled in 2015 that the patent was invalid, saying the compound it covers was "the inherent result of an obvious process."
Takeda Chief Executive Christophe Weber said in 2015 that the ruling, if upheld, would lead to generic competition as soon as late 2017 and cause a "rapid loss" in revenue for Takeda.
But the appeals court said in a unanimous opinion on Monday that the lower court "clearly erred" and the patent is valid, restoring Takeda's market exclusivity until the patent expires in 2022.
Teva spokeswoman Elizabeth Deluca said the company was disappointed in the ruling.
The generic drug companies Sun Pharmaceutical Industries Ltd, Glenmark Pharmaceuticals Ltd and Wockhardt Ltd have also sought to sell versions of Velcade.
Anticipating generic Velcade sales, Takeda has rolled out a follow-up multiple myeloma treatment called Ninlaro. That drug is taken orally, unlike Velcade, which is administered intravenously.
Weber said in 2016 that Ninlaro will eventually generate $3 billion in annual sales.
Reporting by Jan Wolfe in New York; Editing by Anthony Lin and Matthew Lewis