- Merck and Simtra BioPharma Solutions formed a five-year strategic alliance for ADC manufacturing
- Partnership combines Merck’s bioconjugation expertise with Simtra’s fill-finish capabilities to create a streamlined solution
Merck and Simtra BioPharma Solutions announced a five-year strategic alliance in June 2025 to provide integrated antibody-drug conjugate (ADC) manufacturing services from drug substance through fill-finish.
The partnership addresses the need to coordinate multiple contract manufacturers across the complex supply chain, a major pain point in ADC development. Under the alliance, Merck will handle bioconjugation of the drug substance, which is then directly transferred to Simtra for drug product fill-finish.
“By bringing together two experts in the ADC value chain, biopharmaceutical companies should benefit from shorter timelines and less complexity,” said Franco Negron, CEO of Simtra BioPharma Solutions.
Manufacturing ADCs requires combining three distinct components: a monoclonal antibody, a cytotoxic payload, and a linker. Each has its own production challenges. Most biopharmaceutical companies currently work with multiple CDMOs to develop these components separately, then perform conjugation, purification, and fill-finish across different facilities.
The alliance provides designated project managers at each partner’s site to coordinate seamlessly and maintain transparency throughout the drug substance to drug product process. Clients will receive separate but concurrent proposals from both partners, with harmonized timelines and integrated formulation development.
Combined Capabilities
Merck brings more than 15 years of conjugation expertise, with a track record of supporting over 80 INDs and manufacturing more than 30 commercial GMP batches. The company was the first commercially approved ADC manufacturer in North America.
Simtra BioPharma Solutions, an independent CDMO established from Baxter’s BioPharma Solutions business, has more than 65 years of sterile injectable manufacturing experience. The company has transferred more than 60 ADC programs for 15 distinct clients, including six commercially approved products.
With over 200 new ADCs in active clinical trials, it is critical to speed up the manufacturing process, reduce the risk of knowledge or time-loss during handoffs, and enable clients to advance their programs.
The alliance aims to streamline CDMO screening and selection, optimize scheduling, facilitate testing and material onboarding, and maintain transparency on the entire drug substance to drug product process.
The Life Science business of Merck KGaA, Darmstadt, Germany, operates as MilliporeSigma in the U.S. and Canada.
