HALO Wins Court Order Blocking Merck's Keytruda SC in Europe

HALO scored a patent win against MRK in Europe. A Dutch patent court ruled that MRK's Keytruda subcutaneous formulation infringes HALO's MDASE patent. The court ordered MRK to cease manufacturing and sales of the product across eight European markets.

The scope matters. The ruling does not touch Keytruda's intravenous version, so the injunction targets only the subcutaneous formulation. HALO also stated that its separate ENHANZE technology and licensing business remain unaffected by the decision.

This is not HALO's first legal victory over MRK. Zacks Investment Research describes the Dutch order as another win in the ongoing dispute, which suggests HALO has built momentum in its patent campaign. Interpretation: an eight-market manufacturing and sales ban gives HALO real negotiating leverage, though the source does not say whether either side is pursuing a settlement or license.

For context, the cleanly drawn lines in this ruling limit the collateral damage. Keytruda IV continues unimpeded, and HALO's ENHANZE franchise stays outside the dispute. The market impact therefore centers on the subcutaneous Keytruda rollout in Europe rather than the broader Keytruda franchise.