BOSTON Sanofi SA and Regeneron
Pharmaceuticals Inc have filed a lawsuit seeking a
court order declaring that their eczema drug Dupixent, awaiting
a U.S. approval decision, does not infringe an Amgen Inc patent for a failed asthma treatment.
The lawsuit, filed in federal court in Boston on Monday, was
intended to preempt one expected to be brought by Amgen, which
has previously sued Sanofi and Regeneron over their rival
cholesterol drug Praluent.
“Sanofi and Regeneron wish to eliminate any potential
obstacle Amgen might seek to raise against the planned U.S.
commercialization of Dupixent,” the plaintiffs said in the
Amgen said in a statement on Tuesday that the company “does
have a patent covering the product and we will defend our patent
The suit came two months after a federal judge in Delaware
blocked Sanofi and Regeneron from selling Praluent because it
was found to infringe Amgen’s Repatha patent. Praluent was
allowed to remain on the market during the appeals process.
Sanofi and Regeneron argue they have spent hundreds of
millions of dollars developing Dupixent.
The injectable drug, known chemically as dupilumab, is seen
as a critically important future growth driver for both
companies, with annual sales forecast to exceed $5 billion by
2023, according to Thomson Reuters data.
The companies have called Dupixent a “game-changer” in moderate-to-severe atopic dermatitis, a type of eczema that
causes extreme itching. The lawsuit said plans were under way to
begin selling Dupixent as soon as it wins approval from the U.S.
Food and Drug Administration, a decision due next week.
The patent at issue in the lawsuit was issued to Amgen in
the 2000s, when it was attempting to develop an asthma
treatment. Amgen abandoned development of the drug following
disappointing results, the lawsuit said.
The complaint said that in recent days lawyers for Sanofi
and Regeneron learned Amgen had hired lawyers to pursue patent
infringement litigation related to Amgen’s work on that
treatment. Dupilumab is also being tested for asthma and other
“We took this proactive step to protect the value of our
innovative therapy Dupixent and ensure access of this important
medicine for physicians and patients,” Sanofi said in a
statement on Tuesday.
The case is Sanofi-Aventis U.S. LLC et al v. Amgen Inc et
al, U.S. District Court, District of Massachusetts, No.
17-cv-10465. (Additional reporting by Bill Berkrot in New York)