UK pharmaceutical company GSK is suing US rival Moderna for allegedly infringing its mRNA technology patents used in Covid and respiratory syncytial virus (RSV) vaccine products.

GSK filed two lawsuits at the US District of Delaware on 15 October saying that Moderna’s mRNA vaccine product Spikevax infringed up to seven patents covering lipid mRNA vaccine formulation technology. It is also suing Moderna for infringing the same mRNA technology through the sale of its recently approved RSV shot mResvia.

Seeking damages for the alleged infringing activity, GSK claims Moderna has “reaped billions of dollars in revenue” from infringing its patents and continues to benefit, without ever obtaining a licence.

The named inventors of the patents-in-suit is a team led by Christian Mandl. The Mandl team’s innovation has been “revolutionary for vaccine development”, says GSK in the court documents. It adds that a significant advantage over other approaches to vaccine design is the ability to employ the technology across a wide range of viruses.

GSK is the owner of the asserted patents as the Mandl team began working on mRNA vaccines when they were employed by Novartis, which GSK subsequently acquired a portion of, including the Mandl team’s inventions.

GSK contends that years before marketing the products in contention, “Moderna obtained technical know-how relating to GSK biologicals’s mRNA vaccine platform technology by hiring several former Novartis and GSK employees with first-hand knowledge of the Mandl team’s innovations”. 

GSK brings this suit to recover a “reasonable royalty” for Moderna’s alleged infringing sales of mRNA vaccines that apply the Mandl team’s inventions.

A Moderna spokesperson said it “is aware of the litigation and will defend ourselves against these claims”.

This is the latest salvo in the battle surrounding the blockbuster Covid-19 vaccines.

In April, GSK sued Pfizer and German partner BioNTech in Delaware for allegedly infringing patents covering the same technology developed by the Mandl team.

In 2022, Moderna sued Pfizer and its German partner BioNTech over its Comirnaty Covid product. The multi-jurisdictional litigation between the three companies is taking place in the US, the UK, Germany, Belgium, the Netherlands and the European Patent Office.

In July, Moderna secured a partial win in the UK High Court which found one Moderna patent to be valid and infringed by Pfizer and BioNTech although the other was found to be invalid.

At the end of September, UK High Court judge Richard Meade gave Pfizer and BioNTech permission to appeal the decision.

Litigation surrounding RSV vaccines has also been hotting up – last week a London court ruled that two GSK RSV vaccine patents were invalid in an action involving Pfizer, as both companies battle to become the first to launch an RSV vaccine on the UK market.