November 4, 2025 --RAHWAY, N.J.--(BUSINESS WIRE)-- Merck (NYSE: MRK), known as MSD outside of the United States and Canada, today announced that the company, through a subsidiary (Prometheus BioSciences), has reached an agreement with Dr. Falk Pharma GmbH (Falk) to discontinue an existing contract concerning co-development and co-commercialization rights in certain territories for MK-8690 (formerly PRA-052), and for Merck to assume full responsibility for the development program going forward. MK-8690 is an investigational anti-CD30 ligand monoclonal antibody being evaluated by Merck in an early-stage clinical trial.
Under the terms of the agreement, Prometheus BioSciences (Prometheus) and Falk have discontinued their collaboration based on their existing co-development contract resulting in Prometheus having secured global rights to MK-8690. In exchange, Falk will receive a $150 million upfront payment and is eligible to receive a payment associated with a development milestone as well as royalties on sales in certain territories. The original contract between Falk and Prometheus was signed in 2020. Merck subsequently acquired Prometheus in 2023.
As a result of the transaction with Falk, Merck will record a pre-tax charge to research and development expenses of $150 million, or approximately $0.05 per share, in both its GAAP and non-GAAP fourth quarter results.
About Merck
At Merck, known as MSD outside of the United States and Canada, we are unified around our purpose: We use the power of leading-edge science to save and improve lives around the world. For more than 130 years, we have brought hope to humanity through the development of important medicines and vaccines. We aspire to be the premier research-intensive biopharmaceutical company in the world – and today, we are at the forefront of research to deliver innovative health solutions that advance the prevention and treatment of diseases in people and animals. We foster a diverse and inclusive global workforce and operate responsibly every day to enable a safe, sustainable and healthy future for all people and communities.