Fed Circ affirms Eli Lilly victories over cancer drugs
The US Court of Appeals for the Federal Circuit last week affirmed two findings that Dr Reddy’s and Hospira had infringed Eli Lilly’s cancer drug Alimta (pemetrexed).
In a precedential decision, handed down on Friday, August 9, the Federal Circuit ruled that Dr Reddy’s and Hospira’s proposed drugs performed equivalently to Eli Lilly’s patent-protected treatment.
However, the Federal Circuit did reverse the US District Court for the Southern District of Indiana’s finding of literal infringement in the Hospira decision as “clearly erroneous” in light of the court’s claim construction of “administration of pemetrexed disodium”.
“These appeals were taken from cases which are among the latest in a series of patent disputes about Alimta that reaches back more than a decade,” said the Federal Circuit.
Both Dr Reddy’s and Hospira infringed US patent 7,772,209, which covers a method of administering the chemotherapy drug pemetrexed disodium with folic acid and vitamin B12 to reduce the incidence of patient toxicity caused by Alimta. It expires in May 2022.
Dr Reddy’s had filed a New Drug Application with the Food and Drug Administration for pemetrexed ditromethamine in 2015 and, in February the following year, Eli Lilly sued Dr Reddy’s for patent infringement. The Hospira case proceeded along much the same lines.
The district court found that both Dr Reddy’s and Hospira had infringed under the doctrine of equivalents, decisions which both appealed against.
Dr Reddy’s and Hospira, along with amicus curiae Actavis, argued that the district court erred as a matter of law by refusing to apply prosecution history estoppel to bar Lilly’s doctrine of equivalents claim.
Indian company Dr Reddy’s also argued that the disclosure-dedication rule precludes Eli Lilly’s equivalents claim.
The Federal Circuit said that the main dispute in these appeals is whether Eli Lilly has rebutted the presumption of prosecution history estoppel that attached to its amendment in its parent application 10/297,821.
Eli Lilly originally sought broad claims to methods of “administering an antifolate in conjunction with a methylmalonic acid lowering agent, with or without folic acid”. Following examination, Eli Lilly amended its claims to narrow “antifolate” to “pemetrexed disodium” and cancelled its dependent claim limited to pemetrexed disodium.
The Federal Circuit sided with Eli Lilly on estoppel, finding that Dr Reddy’s and Hospira’s view of prosecution history estoppel, and the tangential exception in particular, was “too rigid”.
Circuit Judge Alan Lourie concluded: “In summary, these cases are eminently suitable for application of the doctrine of equivalents, and we conclude that neither prosecution history estoppel nor the disclosure-dedication rule bars Lilly from asserting infringement through equivalence.”
Each of the parties was ordered to bear their own costs.
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