A Munich Regional Court issued a preliminary injunction on Thursday, December 4, 2025, directing Merck & Co. to halt the distribution and sale of its subcutaneous Keytruda (Keytruda SC) in Germany. The order was issued in a patent dispute with Halozyme Therapeutics, which alleges that Merck’s formulation infringes its MDASE patents, specifically European Patent No. 2 797 622.
The injunction bars Merck from offering Keytruda SC in the German market until the court resolves the underlying patent conflict. The decision does not affect the availability of the intravenous version of Keytruda, so patients in Germany can still receive the drug through the traditional infusion route. The ruling represents a significant setback for Merck’s launch strategy, which had positioned the subcutaneous formulation as a way to extend Keytruda’s market exclusivity and provide a more convenient administration option for patients and clinicians.
Merck’s Keytruda portfolio is a cornerstone of its oncology business, generating roughly $29.5 billion in revenue in 2024. The company had recently secured European Commission approval for Keytruda SC in November 2025, and the German injunction delays the product’s commercial rollout in a key European market. Analysts view the injunction as a headwind that could reduce Merck’s projected revenue from the subcutaneous product in 2026 and beyond, while also exposing the company to potential biosimilar competition once the original Keytruda patent expires in 2028.
Merck has publicly disagreed with the ruling, calling Halozyme’s patents invalid and asserting that its own formulation was developed independently. The company has initiated separate proceedings in Germany to challenge the patent’s validity and is monitoring the case closely. Halozyme’s chief legal officer, Mark Snyder, expressed satisfaction with the court’s decision, noting it strengthens the company’s broader enforcement efforts against Merck’s Keytruda SC in both Europe and the United States.
The injunction underscores the broader strategic importance of Keytruda SC for Merck. By offering a subcutaneous version that can be administered in one to two minutes versus a 30‑minute infusion, Merck aims to capture a larger share of the oncology market and mitigate the impact of the original drug’s impending patent cliff. The EU approval of Keytruda SC less than a month before the injunction highlights the rapid pace of regulatory and legal developments surrounding this product line.
The content on BeyondSPX is for informational purposes only and should not be construed as financial or investment advice. We are not financial advisors. Consult with a qualified professional before making any investment decisions. Any actions you take based on information from this site are solely at your own risk.