Merck & Co., Inc. (MRK)[Tv]

Key Developments

• Merck voluntarily withdrew its Biologics License Application (BLA) for ifinatamab deruxtecan (I-DXd) in extensive-stage small cell lung cancer (ES-SCLC) due to safety concerns, including a 12.4% rate of treatment-related interstitial lung disease and two fatal cases—a major strategic setback that exposes deep vulnerabilities in Merck’s ADC pipeline and raises serious questions about its ability to deliver next-generation oncology therapies beyond Keytruda.

• The Dutch court blocked Merck’s subcutaneous Keytruda formulation (KEYTRUDA QLEX) in eight major European markets over a patent infringement ruling by Halozyme Therapeutics—a critical legal blow that threatens a key growth driver, undermines Merck’s IP strategy, and jeopardizes commercial momentum in a high-value region.

• Merck and Moderna’s intismeran autogene (V940), a personalized mRNA cancer vaccine, achieved both primary and secondary endpoints in a pivotal phase 3 trial when combined with Keytruda—marking the first time an mRNA therapy surpassed a PD-1 inhibitor in late-stage oncology, validating Merck’s platform and positioning it at the forefront of a potentially $50B+ market.