By Blake Brittain

July 15 (Reuters) - Sanofi SASY.PA has sued Pfizer PFE.N and Moderna MRNA.O, alleging that their COVID-19 vaccines infringe several of the French pharmaceutical company's patents.

The two lawsuits filed on Tuesday in New Jersey federal court allege that the blockbuster vaccines violate Sanofi's patent rights in messenger RNA (mRNA) innovations.

The cases add to a web of high-stakes patent lawsuits filed by biotech companies against Pfizer and Moderna over the mRNA technology used in their COVID vaccines.

Spokespeople for Pfizer and Moderna did not immediately respond to requests for comment on Sanofi's new lawsuits on Wednesday. A Sanofi spokesperson said on Wednesday that the company is "seeking fair compensation for use of its patented technology" and not seeking to block sales of the vaccines.

Pfizer and Moderna's shots use molecules called lipid nanoparticles (LNPs) to transport mRNA into the body. Sanofi said in its complaints that their LNP technology infringes patents covering LNP technology developed by its mRNA-focused subsidiary Translate Bio.

Sanofi acquired Massachusetts-based Translate for $3.2 billion in 2021 to bolster its mRNA capabilities.

Companies including GlaxoSmithKline, Bayer and Alnylam Pharmaceuticals ​have ⁠also filed patent lawsuits seeking shares of Pfizer and Moderna's tens of billions of dollars of revenue from ⁠COVID-19 ​vaccine sales.

Moderna sued Pfizer for patent infringement in 2022, in a case that is still ongoing. Pfizer's partner BioNTech countersued Moderna in February, arguing Moderna's ⁠next-generation ​COVID-19 shot, mNEXSPIKE, infringes one of its patents.

The cases are Translate Bio Inc v. Moderna Inc, U.S. District Court for the District of New Jersey, No. 2:26-cv-08690 and Translate Bio Inc v. Pfizer Inc, U.S. District Court for the District of New Jersey, No. 2:26-cv-08697.

For Sanofi: Sarah Chapin Columbia and Sarah Fischer of McDermott Will & Schulte

For Moderna and Pfizer: attorney information not yet available