Halozyme wins The Hague injunction blocking Merck’s Keytruda SC in eight European markets

The supplied evidence identifies a concrete, forward-looking legal development rather than market commentary: on October 7, 2026, the District Court of The Hague found Merck infringed Halozyme’s European patent EP 2,797,622 and ordered MSD BV to stop manufacturing, offering, selling, using, importing, or stocking subcutaneous Keytruda in eight European markets. The injunction creates an immediate constraint on Merck’s Keytruda SC commercialization while intravenous Keytruda remains available, supporting a high importance score but somewhat limiting the total product impact. Surprise is material but below shock levels because the ruling follows earlier Keytruda SC patent litigation and a prior German preliminary injunction. HALO, MRK, and 196170.KQ are approved because Halozyme is the patent holder, Merck is directly subject to the injunction, and the enjoined product explicitly uses Alteogen’s ALT-B4 technology; competing companies are excluded because any benefit to them is speculative and not evidenced by an actual shift in demand or market share. The real-world date is explicit, but no exact court-order time is provided, so the timestamp uses a UTC date-normalization estimate rather than the publication time. The development is approved for downstream use.