Merck launches build-to-buy Saturnus Bio with $50m
Merck KGaA has partnered with Versant Ventures to launch Saturnus Bio, a new biotech developing precision medicines for rare genetic cardiomyopathies.
Why it matters: Genetic cardiomyopathies are serious inherited heart muscle diseases with few treatment options that address the underlying genetic drivers. For Merck, the deal extends its established cardiometabolic business into precision cardiology, starting with rare genetic cardiomyopathies.
Zoom in: The collaboration includes a $50 million upfront payment from Merck to fund Saturnus’ research. In return, Merck gets a minority equity stake and exclusive rights to acquire Saturnus later through a pre-agreed option payment, plus success-based earnouts.
How it works: Saturnus is developing therapies that use targeted gene modulation to treat rare monogenic cardiomyopathies – diseases caused by mutations in a single gene. The company says its goal is to build a pipeline of first-in-class medicines for these conditions.
The context: Build-to-buy deals give pharma companies a way to help shape a young biotech from the start while delaying a full acquisition decision until early milestones are reached. Versant has a track record with company-creation deals that later turned into acquisitions.
- Bayer acquired the remaining stake in BlueRock Therapeutics in 2019, three years after launching the cell therapy company with Versant and a $225 million investment. The deal valued BlueRock at around $1 billion.
- Roche also exercised its option to acquire Inception 5, a company it created with Versant to focus on remyelination therapies for multiple sclerosis.
- More recently, AstraZeneca exercised its option to acquire SixPeaks Bio, a Swiss obesity biotech launched with Versant in 2024.
What they’re saying: “The launch of Saturnus through a foundational partnership with Merck exemplifies Versant’s strategy of engaging with pharma to develop a new frontier of medicines in areas of important unmet medical need,” said Rick Dewey, MD, an entrepreneur-in-residence at Versant Ventures and CEO of Saturnus.
Yes, but: Saturnus is still at the research stage. The companies did not disclose the specific genes, disease subtypes, modality or development timelines behind the platform.
The bottom line: Saturnus fits Merck’s 2025 plan to rebuild its healthcare growth through a more balanced pipeline using external innovation alongside internal assets.
