HALOZYME THERAPEUTICS acquisition history

Halozyme acquired Antares Pharma, Inc. (NASDAQ: ATRS), a Ewing, NJ-based specialty pharmaceutical and drug-delivery company, for $5.60 per share in cash, valuing Antares at approximately $960 million. The deal was structured as a cash tender offer for all outstanding Antares shares followed by a second-step merger under Section 251(h) of the Delaware General Corporation Law, with Antares becoming a wholly owned subsidiary. Antares brought a best-in-class, differentiated, royalty-revenue-generating auto injector platform plus a commercial specialty business anchored by testosterone replacement therapy products (Xyosted and the Tlando launch). The combination created a leading drug delivery and specialty product company alongside Halozyme's ENHANZE platform. approximately $960 million ($5.60 per share in cash).

The addition of Antares, particularly with its best-in-class auto injector platform and specialty commercial business, augments Halozyme's strategy, further strengthens our position as a leading drug delivery company and extends our strategy to include specialty products. The acquisition of Antares fits well with our previously discussed strategic priorities and provides substantial financial growth potential and disruptive solutions to significantly improve patient experiences and outcomes for emerging and established therapies.Dr. Helen Torley — President and CEO, Halozyme

We are pleased to have reached this agreement with Halozyme, as this transaction showcases the value of Antares' highly complementary business, provides our shareholders with attractive and certain value, and brings together industry-leading expertise and drug delivery platforms to accelerate growth and create new opportunities.Robert F. Apple — President and CEO, Antares Pharma

Halozyme acquired Elektrofi, Inc., a Boston-based biopharmaceutical formulation technology company, under an Agreement and Plan of Merger dated September 30, 2025. The transaction comprised a $750 million upfront payment plus up to three $50 million milestone payments contingent on three separate product regulatory approvals. Elektrofi's breakthrough Hypercon ultra-high concentration microparticle technology enables high protein concentration and reduced injection volume for biologics, expanding opportunities for at-home and healthcare-provider administration. Halozyme acquired Elektrofi to expand its drug delivery technology offerings and extend its licensing/royalty-revenue model and long-duration IP into the 2040s. $750 million upfront plus up to three $50 million milestone payments (up to $900 million total).

We look forward to welcoming Elektrofi's talented team as we embark on our next chapter of drug delivery innovation to continue to drive value for all of our stakeholders including our partners, patients, and shareholders.Dr. Helen Torley — President and CEO, Halozyme

Since Elektrofi's founding, we have been committed to revolutionizing the delivery of biologic therapies so that patients can live life on their terms. Today's announcement brings us closer to achieving that vision. Halozyme's proven industry expertise and capabilities in developing drug delivery licensing businesses will advance our unique Hypercon technology, strengthen existing collaborations, support expansion into new partnerships and accelerate our commercialization strategy.Chase Coffman — CEO and Co-founder, Elektrofi

Halozyme acquired all outstanding equity interests of Surf Bio, Inc., a preclinical biopharmaceutical company developing a proprietary biologic hyperconcentration technology (a protective excipient and spray-dry approach) that enables high-concentration formulations of up to 500 mg/mL for subcutaneous delivery of antibodies and biologics in a single auto-injector shot. $305.0 million total purchase consideration to selling shareholders (plus up to $100.0 million in contingent milestone payments).

During 2025, we advanced our strategic growth roadmap with the acquisitions of Elektrofi and their Hypercon technology and of Surf Bio and their hyperconcentration technology. Both hyperconcentration technologies have long-duration IP into the mid-2040s.Dr. Helen Torley — President and Chief Executive Officer, Halozyme Therapeutics, Inc.