Kezar Life Sciences to Present Topline Results from the PORTOLA Phase 2a Trial Evaluating Zetomipzomib for the Treatment of Patients with Autoimmune Hepatitis on March 25, 2025

SOUTH SAN FRANCISCO, CALIF.--(BUSINESS WIRE)-- Kezar Life Sciences, Inc. (Nasdaq: KZR), a clinical-stage biotechnology company developing novel small molecule therapeutics to treat unmet needs in immune-mediated diseases, today announced that it will present topline results from the PORTOLA Phase 2a trial evaluating zetomipzomib for the treatment of patients with autoimmune hepatitis (AIH) on Tuesday, March 25, 2025, at 8:00 a.m. ET.

The event will highlight topline data from Kezar’s PORTOLA trial, a placebo-controlled, randomized, double-blind Phase 2a clinical trial evaluating the efficacy and safety of zetomipzomib in patients with AIH. Additionally, the event will feature presentations from Craig Lammert, MD, Associate Professor of Medicine at Indiana University School of Medicine and a principal investigator on the PORTOLA trial, and Gideon Hirschfield, PhD, the Lily and Terry Horner Chair in Autoimmune Liver Disease Research, and Director of the Francis Family Liver Clinic at Toronto General Hospital.

A live question and answer session will follow the formal presentation.

To access the live audio webcast with slides and dial-in information as needed, please register here: https://kezar-life-sciences-portola-phase-2a-topline-results.open-exchange.net/.

A live webcast of the event can also be found on the Kezar website at https://ir.kezarlifesciences.com/news-events/events-presentations. A replay of the event will be available for 90 days following the presentation.

About PORTOLA

PORTOLA is a placebo-controlled, randomized, double-blind Phase 2a clinical trial evaluating the efficacy and safety of zetomipzomib in patients with AIH that are insufficiently responding to standard of care or have relapsed. The study has completed enrollment of 24 patients, randomized (2:1) to receive 60 mg of zetomipzomib or placebo in addition to background therapy for 24 weeks, with a protocol-suggested steroid taper. The primary efficacy endpoint will measure the proportion of patients who achieve a complete biochemical response by Week 24 measured as normalization of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and Immunoglobulin G (IgG) values (if elevated at baseline), with steroid dose levels not higher than baseline.

About Craig Lammert, MD

Craig Lammert, M.D., a clinician investigator who focuses on autoimmune hepatitis (AIH), is an Associate Professor of Medicine at Indiana University School of Medicine and also serves as the executive director for the Autoimmune Hepatitis Association (AIHA).

He has focused his research in AIH to better understand the genetic and environmental contributions to AIH and how these could modify outcomes of AIH patients. Dr. Lammert is the principal investigator of the Genetic Repository of Autoimmune Liver Disease and Contributing Exposures (GRACE) Study, a program historically funded by the National Institutes of Health (NIH) to build a database of AIH patients that includes disease phenotypes and outcomes, biologic samples, and environmental exposures.

He has been a strong advocate and supporter of AIH patients beyond the clinic and research realm. Through the AIHA, a US led non-profit organization with international membership of over 9,000 members that he created 13 years ago, he leads patient education conferences, research study recruitment, and support groups for AIH patients. He is an active member of the International Autoimmune Hepatitis Group and the American Association for the Study of Liver Diseases where he currently serves as the vice chairmen for the cholestatic and autoimmune liver disease special interest group. He also is a co-investigator in autoimmune liver disease drug trials and multicenter studies.

About Gideon Hirschfield, MD

Dr Gideon Hirschfield is the Lily and Terry Horner Chair in Autoimmune Liver Disease Research, and Director of the Francis Family Liver Clinic, Toronto General Hospital. He runs the Autoimmune and Rare Liver Disease Program at Toronto General Hospital and spends his time looking after people living with PBC, PSC, AIH and rare liver disease. Trained in the UK with prior faculty appointments in Birmingham, UK, he has developed a unique program in Toronto that encompasses care, teaching and research in the area of autoimmune and rare liver disease.

About Autoimmune Hepatitis

Autoimmune hepatitis (AIH) is a rare chronic disease in which the immune system attacks the liver and causes inflammation and tissue damage, severely impacting patients’ physical health and quality of life. Lifelong maintenance therapy is required to avoid relapse and burdensome adverse effects. If left untreated, AIH can lead to cirrhosis, liver failure and hepatocellular carcinoma. In the United States, AIH affects approximately 100,000 individuals, with incidence rates increasing. The cause of this condition remains unclear, with females affected four times as often as males. Currently, standard of care treatment for AIH is chronic, immunosuppressive treatment with corticosteroids that frequently cause life-altering side effects, including diabetes, osteoporotic fractures and cataracts. There is a significant need for treatment regimens that reduce or remove the need for chronic immunosuppression from using corticosteroids.

About Kezar Life Sciences

Kezar Life Sciences is a clinical-stage biopharmaceutical company developing novel small molecule therapeutics to treat unmet needs in immune-mediated diseases. Zetomipzomib, a selective immunoproteasome inhibitor, is currently being evaluated in a Phase 2a clinical trial for autoimmune hepatitis. This product candidate also has the potential to address multiple chronic immune-mediated diseases. For more information, visit www.kezarlifesciences.com, and follow us on LinkedIn, Facebook, Twitter and Instagram.

Cautionary Note on Forward-looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as “may,” “will,” “can,” “should,” “expect,” “believe,” “potential,” “anticipate” and similar expressions (as well as other words or expressions referencing future events, conditions or circumstances) are intended to identify forward-looking statements. These forward-looking statements are based on Kezar’s expectations and assumptions as of the date of this press release. Each of these forward-looking statements involves risks and uncertainties that could cause Kezar’s clinical development programs, future results or performance to differ materially from those expressed or implied by the forward-looking statements. Forward-looking statements contained in this press release include, but are not limited to, statements about the design, initiation, progress, timing, scope and results of clinical trials, the enrollment and expected timing of reporting topline data from our clinical trials, the likelihood that data will support future development and therapeutic potential, the association of data with treatment outcomes and the likelihood of obtaining regulatory approval of Kezar’s product candidates. Many factors may cause differences between current expectations and actual results, including unexpected safety or efficacy data observed during clinical studies, difficulties enrolling and conducting our clinical trials, changes in expected or existing competition, changes in the regulatory environment, the uncertainties and timing of the regulatory approval process, and unexpected litigation or other disputes. Other factors that may cause actual results to differ from those expressed or implied in the forward-looking statements in this press release are discussed in Kezar’s filings with the U.S. Securities and Exchange Commission, including the “Risk Factors” contained therein. Except as required by law, Kezar assumes no obligation to update any forward-looking statements contained herein to reflect any change in expectations, even as new information becomes available.

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Investor and Media Contact:

Gitanjali Jain

Senior Vice President, Investor Relations and External Affairs

Kezar Life Sciences, Inc.

gjain@kezarbio.com

Source: Kezar Life Sciences, Inc.