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 data from RUBY-1, a phase 1 study of povetacicept in healthy adult volunteers, at multiple upcoming scientific congresses, including participation in a poster tour at the European Congress of Rheumatology (EULAR) and an oral presentation at the European Hematology Association (EHA).

15^th annual International Congress on Systemic Lupus Erythematosus/43^rd KCR Annual Scientific Meeting

Date/Time: May 20, 2023 at 14:30 - 15:30 KST

Presentation Title: A Placebo-Controlled Phase 1 Study in Healthy Adult Volunteers of the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Povetacicept, a Potent Dual BAFF/APRIL Antagonist, for the Treatment of Systemic Lupus Erythematosus

Poster Number: LSO-090

Session Name: Short Oral Presentation Session 16, SLE Treatment 2

Location: Conference Room 205 B, COEX Convention Center, Seoul, South Korea

EULAR

Date/Time: June 1, 2023 at 12:00-13:30 CEST

Poster Title: A Placebo-Controlled Phase 1 Study in Healthy Adult Volunteers of the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Povetacicept (ALPN-303), a Potent Dual BAFF/APRIL Antagonist, for the Treatment of Systemic Lupus Erythematosus and Other B Cell-Related Disorders (RUBY-1)

Poster Number: POS0114

Session Name: A novel journey into SLE, Sjögren's and APS

Location: Poster Tour Auditorium 12, MiCo Convention Center, Milan, Italy

EHA

Date/Time: June 10, 2023 at 16:30 - 17:45 CEST

Poster Title: Povetacicept (ALPN-303), A Potent Dual BAFF/APRIL Antagonist, for the Treatment of Autoimmune Cytopenias and Other Antibody-Related Diseases

Presentation ID: S276

Session Name: s441 Translational research in rare anemias

Location: Panorama 2, Congress Centre, Forum, Festhalle and Halls 1 and 3 of Messe Frankfurt, Frankfurt, Germany

European Renal Association (ERA)

Date/Time: June 17, 2023 at 17:00 - 18:15 CEST

Presentation Title: Phase 1 Study of the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Povetacicept for Autoimmune Glomerulonephritides

Session Name: The ANCA Vasculitis Variety Session

Location: Amber 3 & 4, MiCo, Milan Convention Centre, Milan, Italy

About Povetacicept (ALPN-303) and the RUBY-1 Phase 1 Study

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 the activation and survival of B cells, particularly antibody-secreting cells. Based upon an engineered TACI (transmembrane activator and CAML interactor) domain, povetacicept exhibits greater potency in preclinical studies versus wild-type TACI-based comparators, as well as other inhibitors of BAFF and/or APRIL alone. Povetacicept is in development for multiple B cell and/or autoantibody-related diseases, such as systemic lupus erythematosus, autoimmune glomerulonephritis, and autoimmune cytopenias.

RUBY-1 (NCT05034484) is a phase 1 study in healthy adult volunteers designed to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of single doses of intravenously and subcutaneously administered povetacicept. Povetacicept was well tolerated at doses up to 960 mg, with dose-dependent pharmacokinetics and reductions in circulating immunoglobulins and antibody-secreting cells, supporting the use of a once every four-week dose regimen for subsequent studies.

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

This release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, Section 21E of the Securities Exchange Act of 1934 and the Private Securities Litigation Reform Act of 1995. These forward-looking statements are not based on historical fact and include statements regarding our platform technology and potential therapies; the potential efficacy, safety profile, future development plans, addressable market, regulatory success, and commercial potential of our product candidates; and the timing of our public presentations and potential publication of future clinical data. Forward-looking statements generally include statements that are predictive in nature and depend upon or refer to future events or conditions and include words such as “may,” “will,” “should,” “would,” “expect,” “plan,” “intend,” and other similar expressions, among others. These forward-looking statements are based on current assumptions that involve risks, uncertainties, and other factors that may cause actual results, events, or developments to be materially different from those expressed or implied by such forward-looking statements. These risks and uncertainties, many of which are beyond our control, include, but are not limited to: clinical trials may not demonstrate safety and efficacy of any of our product candidates; our ongoing discovery and preclinical efforts may not yield additional product candidates; our discovery-stage and preclinical programs may not advance into the clinic or result in approved products; any of our product candidates may fail in development, may not receive required regulatory approvals, or may be delayed to a point where they are not commercially viable; we may not achieve additional milestones in our proprietary or partnered programs; the impact of competition; adverse conditions in the general domestic and global economic markets; the impact of the COVID-19 pandemic on our business, research and clinical development plans and timelines and results of operations, including the impact on our clinical trial sites, collaborators, and contractors who act for or on our behalf, may be more severe and prolonged than currently anticipated; as well as the other risks identified in our filings with the Securities and Exchange Commission. These forward-looking statements speak only as of the date hereof and we undertake no obligation to update forward-looking statements, and readers are cautioned not to place undue reliance on such forward-looking statements.

View source version on businesswire.com: https://www.businesswire.com/news/home/20230519005392/en/