Senator Warren Urges US Patent Office to Scrutinize Merck's Keytruda

Michael Erman

February 27, 2023

NEW YORK (Reuters) - U.S. Senator Elizabeth Warren has sent the nation's top patent regulator a letter urging close scrutiny of Merck & Co's requests for new patents on its blockbuster cancer treatment Keytruda, saying further efforts to protect the drug could be an abuse of the system.

"It is not at all clear that Merck is doing anything other than extending its monopoly power over the drug," Warren wrote to Kathi Vidal, director of the United States Patent and Trademark Office (PTO) in the letter sent on Wednesday and seen by Reuters.

Senator Bernie Sanders, as well as Representatives Katie Porter and Pramila Jayapal also signed the letter. All four members of Congress are Democrats.

They expressed particular concern over Merck's efforts to patent a subcutaneous version of the currently infused drug, which Reuters reported on late last year.

They wrote that Merck’s use of dozens of patents to fend off Keytruda competitors "appear(s) to be an example of the anti-competitive business practices ... that we have long been concerned about."

Merck, which reported $20.9 billion in 2022 sales of Keytruda, has relied on the immunotherapy to fuel its growth.

The treatment, first approved in 2014, harnesses the body's own immune system to fight cancers with dramatic results. Against advanced lung cancer, it has led to a five-year survival rate in about one-quarter of people compared to 5% historically for the disease.

It initially demonstrated impressive survival benefits in the deadliest form of skin cancer and has since been approved for many types of cancer.

The members of Congress wrote that subcutaneous injections do not represent novel improvements for drugs, as "medications have been injected under the skin since insulin was discovered in 1921."

They urged Vidal to "give close scrutiny to any of Merck’s requests for new patents for Keytruda, and reject those that do not clearly meet the agency’s standards."

(Reporting by Michael Erman; Editing by Bill Berkrot)