Warren urges US patent office to scrutinize Merck's efforts with Keytruda

With several measures aimed at controlling rising drug prices, the Inflation Reduction Act was a long-awaited victory for the U.S. government over the pharma industry.

But the emboldened Senate isn’t stopping there. Led by Sens. Elizabeth Warren, D-Massachusetts, and Bernie Sanders, I-Vermont, lawmakers have since taken aim at a variety of pharma issues including mergers and acquisitions, offshoring profits and COVID-19 vaccine prices.

Next up on Warren's agenda: Merck’s attempt to gain fresh patents for oncology megablockbuster Keytruda. Wednesday, Warren sent a letter to the U.S. Patent and Trademark Office (PTO) asking for intense scrutiny of the company’s attempt to extend its patent protection of the drug, which generated $20.9 billion in sales last year.

“It is not at all clear that Merck is doing anything other than extending its monopoly power over the drug,” Warren wrote (PDF) to PTO Director Kathi Vidal.

Also signing the letter were Sanders and House Democrats Katie Porter and Pramila Jayapal.

Keytruda is on schedule to lose its patent protection in 2028, opening the door to biosimilar competition. In response to Warren's letter, the company said it is still pointing to 2028 as the "most likely timeframe for biosimilar entry."

"Merck is continuously innovating to enhance the benefits of Keytruda in order to reach greater numbers of patients and to increase efficacy and convenience of the treatment," the company said. "This includes innovations around composition of matter, method of use, formulation, dosing and combinations with other agents. When appropriate, Merck seeks to protect its additional innovation."

That presumably includes the company's two subcutaneous versions of Keytruda,  an infused drug that has been approved for a wide variety of cancers since it originally hit the market in 2014.

Last month at the J.P. Morgan Healthcare Conference, the president of Merck Research Laboratories, Dean Li, talked up one of the subcutaneous versions, which is being tested against lung cancer, with the trial wrapping up this month.

“I think about it as scientific innovation that drives access to a life-saving medicine," Dean Li, M.D., Ph.D., president of Merck Research Laboratories, said last month at the J.P. Morgan Healthcare Conference. "Especially in the early stage, you have patients [who] don’t want to be tethered. They can't be tethered to an infusion center."

In their letter from Sen. Warren, the leaders pointed out that Merck had—as of October 2021—filed 129 patents linked to Keytruda that could extend its exclusivity to 2036. Fifty percent of the applications were filed after Keytruda was initially approved by the FDA, and 74% cover "different indications and formulations of the drug, not the key antibody," they added.

"These efforts by Merck appear to be part of a long-standing pattern of drug manufacturers’ abuse of the patent system," they wrote, adding that Merck's use of patents is “an example of anti-competitive business practices.”

They also suggested that subcutaneous injections should not reach the level of innovation required for a patent.

In its emailed response on Thursday, Merck pointed to a variety of ways a subcutaneous formulation of Keytruda would improve the patient experience, reduce administration time and improve access.