Father of mRNA vaccines
Dr Drew Weissman (centre top), a professor of Infectious Diseases at Penn’s Perelman School of Medicine, is known as the “father” of messenger RNA biology. Others in the photo (clockwise from top, left) are biochemist Dr Katalin Karikó, Weissman's co-inventor and known as the "mother" of mRNA vaccines; Moderna CEO Stephan Bancel; US scientist Dr Robert Langer Jr; Dr. Ugur Sahin and Dr. Özlem Türeci of BioNTech, and Canadian stem cell biologist Dr Derrick J. Rossi. Moderna, Pfizer and BioNTech are embroiled in patent disputes with each other and against companies over the vaccines. Image Credit: Gulf News File / Supplied

Pfizer Inc and its German partner BioNTech SE fired back at Moderna Inc with counterclaims in a patent lawsuit in Boston federal court on Monday over their rival COVID-19 vaccines, seeking dismissal of the lawsuit and an order that Moderna's patents are invalid and not infringed.

Moderna first sued Pfizer in August, accusing the company of violating its rights in three patents related to innovations that Cambridge, Massachusetts-based Moderna said it pioneered before the COVID-19 pandemic.

Moderna has also filed a related lawsuit against Pfizer and BioNTech in Germany.

All three companies are also embroiled in US patent disputes with other companies over the vaccines.

The companies did not immediately respond to requests for comment on the Monday filing.

Pfizer's COVID-19 vaccine made over $26.4 billion for the New York-based company in the first nine months of 2022, while Moderna sold over $13.5 billion worth of its COVID vaccine over the same period, according to company filings with the US Securities and Exchange Commission.