April 25 (Reuters) - GlaxoSmithKline sued Pfizer and BioNTech in Delaware federal court on Thursday, accusing them of infringing GSK patents related to messenger RNA (mRNA) technology in the companies' blockbuster COVID-19 vaccines.

GSK said in the lawsuit that Pfizer and BioNTech's Comirnaty vaccines violate the company's patent rights in mRNA-vaccine innovations developed "more than a decade before" the outbreak of the COVID-19 pandemic. (Reporting by Blake Brittain)