Astria Therapeutics Initiates the Phase 3 ORBIT-EXPANSE Long-Term Trial of Navenibart in People with Hereditary Angioedema

BOSTON, Mass.--(BUSINESS WIRE)-- Astria Therapeutics, Inc. (NASDAQ:ATXS), a biopharmaceutical company focused on developing life-changing therapies for allergic and immunologic diseases, today announced the initiation of the Phase 3 ORBIT-EXPANSE long-term trial of navenibart in people living with hereditary angioedema (HAE).

“The initiation of ORBIT-EXPANSE marks exciting progress in the development of navenibart,” said Christopher Morabito, M.D., Chief Medical Officer at Astria Therapeutics. "The entrance of eligible and interested participants into the ORBIT-EXPANSE long-term trial following the completion of the pivotal Phase 3 ALPHA-ORBIT trial highlights enthusiasm for navenibart, and we are deeply grateful to trial participants and site facilitators for their continued partnership."

The navenibart Phase 3 program consists of the ALPHA-ORBIT Phase 3 trial and ORBIT-EXPANSE long-term trial, which are designed to support registration globally. After completing ALPHA-ORBIT, eligible participants may continue into the ORBIT-EXPANSE trial, in which all participants will receive navenibart in either Q3M or Q6M regimens. The trial has two parts: in Part 1, participants will receive navenibart in a fixed dosing regimen for at least 6 months and, in Part 2, participants may move from one regimen to another based on their needs via a patient-centered flexible dosing period.

For more information on the ORBIT-EXPANSE long-term trial, please visit clinicaltrials.gov, NCT07204938. To learn more about the currently enrolling Phase 3 ALPHA-ORBIT trial, please visit AlphaOrbit.longboat.com, AstriaTrials.com, or clinicaltrials.gov, NCT06842823.

About Navenibart:
Navenibart is a monoclonal antibody inhibitor of plasma kallikrein in development for the treatment of HAE. Our goal with navenibart is to provide rapid and sustained HAE attack prevention with a validated mechanism and trusted modality administered subcutaneously every 3 and 6 months. We aim to empower people living with HAE to live life without limitations from their disease.

About Astria Therapeutics:
Astria Therapeutics is a biopharmaceutical company, and our mission is to bring life-changing therapies to patients and families affected by allergic and immunologic diseases. Our lead program, navenibart (STAR-0215), is an investigational monoclonal antibody inhibitor of plasma kallikrein in clinical development for the treatment of hereditary angioedema. Our second program, STAR-0310, is an investigational monoclonal antibody OX40 antagonist in clinical development for the treatment of atopic dermatitis. Learn more about our company on our website, www.astriatx.com, or follow us on Instagram @AstriaTx and on Facebook and LinkedIn.

Forward-Looking Statements:
This press release contains forward-looking statements within the meaning of applicable securities laws and regulations including, but not limited to, statements regarding: the goals and objectives of the ALPHA-ORBIT and ORBIT-EXPANSE trials; the potential of navenibart as a treatment for HAE and its potential profile; and our corporate strategy and vision, including our mission is to bring life-changing therapies to patients and families affected by allergic and immunologic diseases. The use of words such as, but not limited to, “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “goals,” “intend,” “may,” “might,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “will,” “would,” or "vision," and similar words expressions are intended to identify forward-looking statements. Forward-looking statements are neither historical facts nor assurances of future performance. Instead, they are based on Astria’s current beliefs, expectations and assumptions regarding the future of its business, future plans and strategies, future financial performance, results of pre-clinical and clinical results of the Astria’s product candidates and other future conditions. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including risks and uncertainties related to: changes in applicable laws or regulations; the possibility that we may be adversely affected by other economic, business, and/or competitive factors; risks inherent in pharmaceutical research and development, such as: adverse results in our drug discovery, preclinical and clinical development activities, the risk that the results of preclinical studies may not be replicated in clinical trials, that the preliminary, initial or interim results from clinical trials may not be indicative of the final results, that the results of early stage clinical trials, such as the results from the ALPHA-STAR Phase 1b/2 clinical trial and ALPHA-SOLAR clinical trial, may not be replicated in later stage clinical trials, such as ALPHA-ORBIT, the risk that we may not be able to enroll sufficient patients in our clinical trials on a timely basis, and the risk that any of our clinical trials may not commence, continue or be completed on time, or at all; decisions made by, and feedback received from, the U.S. Food and Drug Administration and other regulatory authorities on our regulatory and clinical trial submissions and other feedback from potential clinical trial sites, including investigational review boards at such sites, and other review bodies with respect to navenibart, STAR-0310, and any other future development candidates; our ability to manufacture sufficient quantities of drug substance and drug product for navenibart, STAR-0310, and any other future product candidates on a cost-effective and timely basis, and to develop dosages and formulations for navenibart, STAR-0310, and any other future product candidates that are patient-friendly and competitive; our ability to develop biomarker and other assays, along with the testing protocols therefor; our ability to obtain, maintain and enforce intellectual property rights for navenibart, STAR-0310 and any other future product candidates; our potential dependence on collaboration partners; competition with respect to navenibart, STAR-0310, or any of our other future product candidates; the risk that survey results, modeling data and market research may not be accurate predictors of the commercial landscape for HAE, the ability of navenibart to compete in HAE and the anticipated position and attributes of navenibart in HAE based on clinical data to date, its preclinical profile, pharmacokinetic modeling, market research and other data; risks that any of our clinical trials of STAR-0310 may not commence, continue or be completed on time, or at all; risks that results of preclinical studies of STAR-0310 will not be replicated in clinical trials; our ability to manage our cash usage and the possibility of unexpected cash expenditures; our ability to obtain necessary financing to conduct our planned activities and to manage unplanned cash requirements; the risks and uncertainties related to our ability to recognize the benefits of any additional acquisitions, licenses or similar transactions; and general economic and market conditions; as well as the risks and uncertainties discussed in the “Risk Factors” section of our Annual Report on Form 10-K for the period ended December 31, 2024 and in other filings that we may make with the Securities and Exchange Commission, including our Quarterly Report on Form 10-Q for the period ended June 30, 2025. New risks and uncertainties may emerge from time to time, and it is not possible to predict all risks and uncertainties. Astria may not actually achieve the forecasts or expectations disclosed in our forward-looking statements, and investors and potential investors should not place undue reliance on Astria’s forward-looking statements.

Neither Astria, nor its affiliates, advisors or representatives, undertake any obligation to publicly update or revise any forward-looking statement, whether as result of new information, future events or otherwise, except as required by law. These forward-looking statements should not be relied upon as representing Astria’s views as of any date subsequent to the date hereof.

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Astria Contact:

Investor Relations and Media:

Elizabeth Higgins

investors@astriatx.com

Source: Astria Therapeutics, Inc.