- GlaxoSmithKline sued Pfizer in U.S. court, alleging patent infringement over GSK's respiratory syncytial virus vaccine.
- Pfizer's RSV vaccine infringes on four of GSK's patents related to the antigen used in its own shot, Britain-based GSK wrote in a scathing complaint filed in federal court in Delaware.
- Both vaccines were approved by the U.S. Food and Drug Administration for use in adults 60 and above.
GSK claims New York-based Pfizer's RSV vaccine, Abrysvo, infringes on four of its patents related to the antigen used in its own shot.
"Upon information and belief, Pfizer knowingly uses GSK's claimed inventions in Abrysvo without permission," GSK wrote in a scathing complaint filed in federal court in Delaware.
RSV is a common respiratory infection that usually causes mild, cold-like symptoms, but more severe cases in older adults and children. Each year, it kills 6,000 to 10,000 seniors and a few hundred children younger than 5, according to CDC data.
GSK is demanding a jury trial and seeking monetary damages, including lost profits and royalties resulting from Pfizer's alleged patent infringement.
The British drugmaker is also asking a judge to prevent Pfizer from manufacturing and selling Abrysvo in the U.S. for adults 60 and older.
GSK said it is not seeking to limit the use of Abrysvo for preventing RSV in infants, a separate shot specifically designed to protect newborns. The FDA is expected to make a final decision on that vaccine in August.
A Pfizer spokesperson said it is "confident in its intellectual property position and will strongly defend its right to bring its innovative" RSV shot to patients.
The lawsuit noted that Pfizer began working on its RSV vaccine program as early as 2013, at least seven years after GSK started its own program.
The suit alleges that Pfizer knew of GSK's patented technology since at least October 2019, when Pfizer began challenging the validity of European versions of the patents.
It's not the first time GSK has waged a legal battle against Pfizer over patent rights.
GSK in 2016 sued Pfizer in court in Ireland, alleging patent infringement over GSK's meningitis vaccine.