Merck Secures $700 Million From Blackstone To Advance Sacituzumab Tirumotecan Development

Merck (NYSE: MRK), known as MSD outside the U.S. and Canada, announced a new funding agreement with Blackstone Life Sciences to support the continued development of its investigational antibody-drug conjugate (ADC) sacituzumab tirumotecan (sac-TMT). The therapy targets the TROP2 protein, which is present on the surface of several cancer types. Sac-TMT is currently being evaluated in 15 Phase 3 clinical trials globally, covering six tumor types, including breast, endometrial, and lung cancers.

Under the agreement, Blackstone will provide Merck with $700 million to help finance development costs for sac-TMT through 2026. In return, Blackstone will receive low-to-mid single-digit royalties on future net sales, contingent upon sac-TMT receiving U.S. regulatory approval for first-line treatment of triple-negative breast cancer based on results from the TroFuse-011 study. Merck will maintain full control over the development, manufacturing, and commercialization of the drug.

Merck stated that this collaboration allows it to advance a promising ADC candidate while sustaining financial discipline and long-term growth. The arrangement does not alter Merck’s existing partnership with Sichuan Kelun-Biotech, which co-develops sac-TMT under an exclusive license agreement. Blackstone’s participation reflects its confidence in the therapeutic and commercial potential of sac-TMT in oncology.