Halozyme Confirms It Projects Zero to Minimal Impact to Royalty Revenue Through At Least 2035 Based on Newly Released Draft Medicare Drug Price Negotiation Program Proposed Rule for IPAY 2029

SAN DIEGO, June 15, 2026 /PRNewswire/ -- Halozyme Therapeutics, Inc. (Nasdaq: HALO) ("Halozyme" or the "Company") today confirmed that the Company expects zero to minimal royalty revenue impact based on its analysis of the proposed rule for the Medicare Drug Price Negotiation Program ("Program") issued by the U.S. Centers for Medicare & Medicaid Services ("CMS") on June 12, 2026.

"Based on our analysis of CMS's proposed rule and the statutory framework established under the One Big Beautiful Bill Act ("OBBBA"), Halozyme projects zero to minimal impact to its royalty revenues through at least 2035. Importantly, there is also no projected impact on the Company's ability to execute new ENHANZE® partnership agreements where improving the patient treatment experience and competitive differentiation continue to be the top reasons ENHANZE is utilized," commented Dr. Helen Torley, President and Chief Executive Officer.

This outlook is supported by statements in the proposed rule affirming that orphan drug protections remain applicable and addressing the impacts of biosimilar entry on Program eligibility.

Halozyme will continue to engage constructively with CMS and other stakeholders to support policies that appropriately recognize innovation and preserve patient access to therapies that improve outcomes and reduce overall healthcare system burden.

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., Skye Bioscience and GSK.

Halozyme expanded its drug delivery technology portfolio to develop partner products using Hypercon™ and Surf Bio's hyperconcentration technology. 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. The addition of Surf Bio'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 Surf Bio's technology 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.

For more information, visit www.halozyme.com and connect with us on LinkedIn.

Forward Looking Statements

In addition to historical information, the statements set forth in this press release include forward-looking statements including, without limitation, statements concerning the Company's expected future financial performance, the Company's expectations of the impact to future royalty revenue and its ability to enter into new ENHANZE® partnership agreements based on its analysis of the proposed rule for the Medicare Drug Price Negotiation Program issued by CMS on June 12, 2026 including statements concerning expectations of the impact on future royalty revenues as a result of implementation of IPAY price negotiations for Part B drugs,  and the assumptions used in deriving these projections, and factors such as orphan drug status and the potential launch of biosimilars resulting in exclusion from Medicare price negotiation. Forward-looking statements regarding the Company's ENHANZE® drug delivery technology include the possible benefits and attributes of ENHANZE® including its potential application to aid in the dispersion and absorption of other injected therapeutic drugs and facilitating more rapid delivery and administration of higher volumes of injectable medications through subcutaneous delivery and potential to decrease treatment burden and provide clinically meaningful benefits to patients, and lowering healthcare system and Medicare costs including enabling administration at lower cost sites of care. These forward-looking statements are typically, but not always, identified through use of the words "expect," "believe," "enable," "may," "will," "could," "can," "durable," "growth," "innovate," "develop," "vision," "potential," "intends," "estimate," "anticipate," "plan," "predict," "probable," "potential," "possible," "should," "continue," and other words of similar meaning and involve risk and uncertainties that could cause actual results to differ materially from those in the forward-looking statements. Actual results could differ materially from the expectations contained in these forward-looking statements as a result of several factors, including possible differences between relevant provisions of the proposed rule used by the Company in its analysis of the potential impact on future royalty revenues and the provisions of the final rule ultimately issued by the CMS,  unexpected changes in the exclusions to Medicare price negotiations or delays in the launch of biosimilars referred to in this presentation, unexpected delays in the Company's ability to enter into new ENHANZE® partnership agreements, unexpected adverse events or patient outcomes, competitive conditions and uncertainties related to future pharmaceutical pricing policies. These and other factors that may result in differences are discussed in greater detail in the Company's most recent Annual Report on Form 10-K and Forms 10-Q filed with the Securities and Exchange Commission, including under the headings "Risk Factors" and "Management's Discussion and Analysis of Financial Condition and Results of Operations". The Company undertakes no obligation to update or revise any forward-looking statements or any other information contained herein

Contacts:

Tram Bui

VP, Investor Relations and Corporate Communications

609-333-7668

tbui@halozyme.com

Sydney Charlton

Teneo

917-972-8407

sydney.charlton@teneo.com

SOURCE Halozyme Therapeutics, Inc.