GSK has sued Pfizer in a US court, alleging infringement of the patents it holds on vaccines for respiratory syncytial virus (RSV).

The lawsuit claims that Pfizer’s Abrysvo infringes on four of GSK’s patents that cover its rival vaccine, Arexvy.

In May, Arexvy became the first RSV vaccine to be approved anywhere in the world after it received approval from the US Food and Drug Administration (FDA). The US approval of Pfizer’s vaccine followed shortly afterwards.

RSV is a common contagious virus characterised by several mild, cold-like symptoms. Although most people can recover within a week or two, older adults are at a high risk for severe disease.

Both companies’ vaccines aim to prevent lower respiratory tract disease caused by RSV in individuals aged 60 years or older and are expected to be available in the US before the next RSV season.

A GSK spokesperson said that "intellectual property protections are the foundation of research-based companies’ ability to drive innovation" and that the lawsuit should not affect the company’s ability to launch Arexvy.

GSK claims in the lawsuit that Pfizer began working on its RSV programme in 2013, seven years after GSK, and alleges that Pfizer knew of GSK’s patented technology since 2019, when it began challenging the validity of European versions of the patents.

Pfizer’s Abrysvo is said to be infringing one or more claims of the GSK patent, with GSK claiming that "Pfizer knowingly used GSK’s claimed interventions in Abrysvo without permission".

The court documents show that GSK is seeking an injunction on the sale of Pfizer’s Abrysvo in the US, along with damages.

Despite this, the company has made no efforts to block the use of Abrysvo to prevent RSV in infants through active immunisation of pregnant women.

The RSV vaccine market is estimated to exceed $5bn and could surpass $10bn by 2030, according to analysts.

Other drugmakers, including Moderna and Bavarian Nordic, are also looking into the RSV market, with candidates currently in late-stage development.

Reference：
https://www.pmlive.com/pharma_news/gsk_files_lawsuit_against_pfizer_over_rsv_vaccine_patent_infringement_1495826