SAN DIEGO, Oct. 7, 2026-- Halozyme Therapeutics, Inc. (Nasdaq: HALO) ("Halozyme" or the "Company") announced today that the specialized Dutch patent court of the Hague has found Merck to be infringing one of its MDASE patents, EP 2,797,622 (EP622) and ordered Merck's central European Market Authorization Holder and worldwide packaging and distribution hub MSD BV to refrain from manufacturing, having manufactured, offering, placing on the market and using, or importing or stocking for these purposes, Keytruda SC in Belgium, Denmark, France, Ireland, Italy, Sweden, Switzerland and the Netherlands. The injunction also forbids MSD to facilitate infringement by its affiliates, including by allowing the use of its European Marketing Authorization. The court also rejected Merck's arguments that EP622 patent is invalid.
"We're very pleased the Dutch court recognized the validity and infringement of Halozyme's MDASE patent EP622 and granted an injunction halting Merck's launch of Keytruda SC in multiple European markets. The MDASE technology was developed through years of rigorous research to enable rapid, high-volume subcutaneous drug delivery," said Mark Snyder, Chief Legal Officer of Halozyme.
Importantly, patients who want to use Keytruda will still have access to the IV version of Keytruda, which is not covered by Halozyme's patent or the court's injunction order.
The Dutch proceedings are part of Halozyme's global enforcement of its MDASE™ patents against infringement by Merck's Keytruda SC. Halozyme previously sued Merck in Germany and was granted a preliminary injunction on December 4, 2025, stopping Merck's launch of Keytruda SC in Germany.
Halozyme has also sued Merck for patent infringement in U.S. federal district court in New Jersey. In that case, Halozyme alleges the subcutaneous formulation of Keytruda, which is being marketed in the U.S. as QLEX, infringes 15 patents that Halozyme filed beginning in 2011 to protect its MDASE™ technology. The patents at issue arise from Halozyme's extensive research into nearly 7,000 modifications to human hyaluronidases. Among their uses, these hyaluronidases pioneered by Halozyme provide a mechanism for the rapid SC administration of therapeutic drugs. Halozyme's comprehensive studies and innovations were a significant advancement to the field of human-derived hyaluronidases.
The MDASE™ patents are not included in Halozyme's ENHANZE® licensing program and are distinct from its ENHANZE® patents. Therefore, the outcome of the global enforcement of its MDASE™ patents against Merck will not impact the ability of any licensee to use ENHANZE®, or the license fees for use of ENHANZE® patents.
About Halozyme
Halozyme is a biopharmaceutical company advancing disruptive solutions to improve patient experiences and outcomes for emerging and established therapies. As the innovators of ENHANZE® drug delivery technology with the proprietary enzyme rHuPH20, Halozyme's commercially-validated solution facilitates the subcutaneous delivery of injected drugs and fluids, reducing treatment burden and improving convenience. ENHANZE® has touched more than one million patient lives through ten commercialized products across over 100 global markets and is licensed to leading pharmaceutical and biotechnology companies including Roche, Takeda, Pfizer, Janssen, AbbVie, Eli Lilly, Bristol-Myers Squibb, argenx, ViiV Healthcare, Chugai Pharmaceutical, Acumen Pharmaceuticals, Merus N.V., GSK, and Incyte.
Halozyme expanded its drug delivery technology portfolio to develop partner products using Hypercon™ and Surf Bio's hyperconcentration technology, recently renamed as Aerocon™. Hypercon™ is an innovative microparticle technology expected to set a new standard in hyperconcentration of drugs and biologics by reducing injection volume for the same dosage and enabling administration in at‑home and healthcare‑provider settings. Aerocon's polymer‑based hyperconcentration technology further broadens the range of biologics that can be delivered subcutaneously, meaningfully expanding the scope of opportunities across therapeutic modalities. Together, Hypercon™ and Aerocon™ complement ENHANZE® by enabling creation and delivery of highly concentrated biologics. The Hypercon™ technology has been licensed to leading biopharmaceutical partners, including Janssen, Eli Lilly, argenx, Vertex Pharmaceuticals and Oruka Therapeutics.
Halozyme also develops, manufactures and commercializes drug-device combination products using advanced auto-injector technologies designed to improve convenience, reliability and tolerability, enhancing patient comfort and adherence. The Company has two proprietary commercial products, Hylenex® and XYOSTED®, partnered commercial products and ongoing development programs with Teva Pharmaceuticals and McDermott Laboratories Limited, an affiliate of Viatris Inc.
Halozyme is headquartered in San Diego, CA, with offices in Ewing, NJ; Minnetonka, MN; and Boston, MA. Minnetonka is also the site of its operations facility.