Company’s primary focus will be the pursuit of expedited development plans for ALPN-303 in multiple autoimmune and inflammatory indications –

SEATTLE, WA, USA I October 24, 2022 IAlpine Immune Sciences, Inc. (NASDAQ: ALPN), a leading clinical-stage immunotherapy company focused on developing innovative treatments for autoimmune and inflammatory diseases, today announced that the Company has voluntarily terminated enrollment in both clinical studies involving davoceticept (ALPN-202), an investigational CD28 costimulator and dual checkpoint inhibitor, including the NEON-1 study of davoceticept as monotherapy and the NEON-2 study of davoceticept in combination with pembrolizumab. Following these decisions, the Company plans to focus its development resources primarily on ALPN-303, a potentially best-in-class dual BAFF/APRIL B cell cytokine inhibitor in development for multiple autoantibody-related inflammatory diseases, as well as acazicolcept (ALPN-101), a potentially first-in-class dual CD28/ICOS inhibitor in development for systemic lupus erythematosus (SLE) in collaboration with AbbVie.

The decision to terminate enrollment in the davoceticept studies was made in the interest of patient safety after the Company was notified of a second death in the NEON-2 study, attributed to cardiogenic shock. The participant, who had metastatic colorectal cancer previously treated with colectomy and multiple prior systemic chemotherapies, had received a single dose each of davoceticept and pembrolizumab. NEON-2 had previously been subject to a partial clinical hold due to a death attributed to cardiogenic shock. The Company is conducting an ongoing, comprehensive assessment of all NEON study participants.

“Patient safety remains our highest priority,” said Mitchell H. Gold, M.D., Executive Chairman and Chief Executive Officer of Alpine. “We have determined it is in the best interest of all patients to terminate enrollment in the davoceticept studies and we will continue to work with the U.S. Food and Drug Administration, Merck, the study Safety Monitoring Committee, and the study investigators to further understand this important safety issue. Davoceticept has shown encouraging signs of clinical activity and it is unfortunate we have not yet been able to identify a safe dose regimen for the combination with pembrolizumab. We will now prioritize the bulk of our development resources towards advancing our lead wholly-owned program ALPN-303 in multiple autoimmune and inflammatory indications, as well as acazicolcept in SLE in collaboration with AbbVie.”

About Davoceticept and the NEON Studies

Davoceticept (ALPN-202) is a first-in-class, conditional CD28 costimulator and dual checkpoint inhibitor intended for the treatment of cancer. Preclinical studies of davoceticept have successfully demonstrated superior efficacy in tumor models compared to checkpoint inhibition alone. In phase 1 studies, davoceticept has demonstrated encouraging clinical activity, especially in renal cell carcinoma, as monotherapy and in combination with pembrolizumab.

NEON-1 (NCT04186637) is a phase 1 monotherapy dose escalation and expansion study in adults with advanced malignancies. NEON-2 (NCT04920383) is a phase 1 dose escalation and expansion combination study of davoceticept (ALPN-202) and pembrolizumab.

About ALPN-303

ALPN-303 is a dual B cell cytokine antagonist being developed for multiple autoimmune and/or inflammatory diseases. Based upon an engineered TACI (transmembrane activator and CAML interactor) domain, ALPN-303 in preclinical studies shows robust inhibition of B cell activating factor/B lymphocyte stimulator (BAFF, BLyS) and a proliferation inducing ligand (APRIL). These two pleiotropic B cell cytokines play key roles in B cell development, differentiation, and survival, and together contribute to the pathogenesis of multiple autoimmune diseases like systemic lupus erythematosus (SLE) and many other autoantibody-related inflammatory diseases. By simultaneously blocking these two cytokines, ALPN-303 has the potential to improve outcomes in patients suffering from severe autoimmune and/or inflammatory diseases. Alpine plans to conduct a phase 2 proof-of-concept study in SLE and open-label basket studies in renal, hematologic, and dermatologic autoimmune diseases, with the first of these anticipated to begin in the first half of 2023.

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.

SOURCE: Alpine Immune Sciences