Alpine Immune Sciences to Present Initial Clinical Data on Povetacicept in Autoimmune Glomerulonephritis in a Late Breaker Poster Session at American Society of Nephrology Kidney Week 2023

Alpine Immune Sciences, Inc. (NASDAQ: ALPN), a leading clinical-stage immunotherapy company focused on developing innovative treatments for autoimmune and inflammatory diseases, announced the Company will present initial clinical data from RUBY-3, a phase 1b/2a study of povetacicept in autoimmune glomerulonephritis including IgA nephropathy, in a late breaking poster presentation at the American Society of Nephrology (ASN) Kidney Week, November 1-5, 2023 in Philadelphia, Pennsylvania. Following the poster presentation, the Company will host an investor event after the close of the market.

American Society of Nephrology ? Kidney Week 2023
Date/Time: Thursday, November 2, 2023, 10:00 am ? 12:00 pm ET
Poster Title: Povetacicept, an Enhanced Dual BAFF/APRIL Antagonist, in Autoantibody-Associated Glomerulonephritis (GN)
Poster Board Number: TH-PO1125
Session Name: Late-Breaking Posters
Location: Exhibit Hall, Pennsylvania Convention Center, Philadelphia
Presenter: James Tumlin, M.D., Professor of Medicine at Emory University School of Medicine, Founder and CEO of NephroNet Clinical Trials Consortium

Investor Event
Date/Time: Thursday, November 2, 2023, at 4:30 pm ? 5:30 pm ET
Link to Webcast: https://bit.ly/48Gk8yH

About Povetacicept (ALPN-303)

Povetacicept (ALPN-303) is a dual antagonist of the BAFF (B cell activating factor) and APRIL (a proliferation inducing ligand) cytokines, which play key roles in pathogenesis of multiple autoimmune diseases via their roles in the activation, differentiation and/or survival of B cells, particularly antibody-secreting cells, as well as T cells and innate immune cells. Based upon an engineered TACI (transmembrane activator and CAML interactor) domain, povetacicept has exhibited greater potency in preclinical studies versus wild-type TACI-based comparators, as well as other inhibitors of BAFF and/or APRIL alone and B cell depletion. Povetacicept is in development for multiple autoimmune diseases, such as systemic lupus erythematosus, autoimmune glomerulonephritis, and autoimmune cytopenias.

About RUBY-3

RUBY-3 (NCT05732402) is a multiple ascending dose, multi-cohort, open label, phase 1b/2a study of povetacicept in autoimmune glomerulonephritis, where povetacicept is being administered subcutaneously for up to 48 weeks. Key endpoints include proteinuria, eGFR, renal response, and disease-related autoantibodies.

About Alpine Immune Sciences

Alpine Immune Sciences is committed to leading a new wave of immune therapeutics. With world-class research and development capabilities, a highly productive scientific platform, and a proven management team, Alpine is seeking to create first- or best-in-class multifunctional immunotherapies via unique protein engineering technologies to improve patients' lives. Alpine has entered into strategic collaborations with leading global biopharmaceutical companies and has a diverse pipeline of clinical and preclinical candidates in development. For more information, visit www.alpineimmunesciences.com. Follow @AlpineImmuneSci on Twitter and LinkedIn.

Forward-Looking Statements

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