-NEON-1 Study of ALPN-202 as a Monotherapy is Unaffected-

SEATTLE, WA, USA I March 07, 2022 I Alpine Immune Sciences, Inc. (NASDAQ: ALPN), a leading clinical-stage immunotherapy company focused on developing innovative treatments for cancer and autoimmune and inflammatory diseases, today announced that the U.S. Food and Drug Administration (FDA) has placed a partial clinical hold on its NEON-2 trial evaluating davoceticept (ALPN-202) in combination with pembrolizumab in adults with advanced malignancies.

The partial clinical hold was prompted by Alpine’s report of a Grade 5 serious adverse event (patient death) in the NEON-2 trial. The participant had choroidal melanoma previously treated with nivolumab and ipilimumab, and had received a single dose each of davoceticept and pembrolizumab. The participant’s death was attributed to cardiogenic shock, considered by the treating physicians as likely related to immune-mediated myocarditis, or possibly infection.

“Patient safety remains, as always, our top priority,” said Mitchell H. Gold, Executive Chairman and Chief Executive Officer of Alpine. “We appreciate the dialogue with FDA and look forward to working diligently with FDA, Merck, the study Safety Monitoring Committee, and the study investigators to further understand this unfortunate event. Given the strong scientific rationale for the combination of davoceticept and pembrolizumab to benefit treatment-refractory patients, we are hopeful that the study will soon be resumed after appropriate safety review, and with appropriate safety precautions in place.”

Patients currently enrolled in the NEON-2 trial may continue to receive davoceticept and pembrolizumab, although no additional patients may be enrolled until the partial clinical hold is resolved. The partial clinical hold does not affect the ongoing NEON-1 clinical trial of davoceticept as monotherapy (NCT04186637).

About Davoceticept (ALPN-202)

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. Completion of dose escalation and initiation of expansion cohorts of NEON-1 (NCT04186637), a Phase 1 monotherapy dose escalation and expansion trial in patients with advanced malignancies, is anticipated in the first half of 2022. NEON-2 (NCT04920383), a combination study of davoceticept (ALPN-202) and pembrolizumab was initiated in June 2021 and is currently on partial clinical hold as described above.

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