Merck Shares Jump 4.9% on Cancer Trial Win as Keytruda Patent Cliff Looms

Merck wants to show it is not just a one-drug company, and Friday’s clinical trial results gave it a boost. Shares rose 4.9% in premarket trading after a partner drug worked well in advanced lung cancer when used with Merck’s main cancer treatment. At the same time, European regulators moved closer to approving another Keytruda combination for bladder cancer. Here’s what these results could mean for Merck’s strategy after its patent expires, and whether its pipeline can make up the difference.

Sichuan Kelun-Biotech, a partner based in China, reported strong late-stage trial results for sacituzumab govitecan, a drug that targets the TROP2 protein found in many cancers. When used with Keytruda, the treatment helped patients with advanced non-small cell lung cancer live longer without their disease getting worse. These patients had not received earlier systemic therapy. The combination reduced the risk of disease progression or death by about 65% compared to Keytruda alone. The study included over 400 advanced-stage patients in China. Early results also suggest patients may live longer overall, but it is too soon to be certain. J.P. Morgan called the results very encouraging and said the data looks solid.

This good news comes at a time when Merck is facing a clear challenge. The main patents for Keytruda, one of the top-selling drugs ever, will start to expire in 2028. After that, similar competing drugs are expected to enter the market. Merck’s CEO has said the company’s plan is to protect its position by creating new drug combinations and finding more uses for its medicines, which could extend some protections to 2029. Sac-TMT is one of several antibody-drug conjugates Merck is working on with Kelun-Biotech, a partnership that began in 2022 with a $100 million investment.

European regulators also boosted Friday’s positive news by recommending approval of a Keytruda and Padcev combination for patients with muscle-invasive bladder cancer. This recommendation is based on Phase 3 data that showed better event-free survival. Padcev, which is co-developed by Pfizer and Japan’s Astellas Pharma, is already approved for this use in the United States