Arcus Biosciences to Present Updated Data from the Phase 1 Safety Dose-Escalation Portion of the AB928 Combination Trials at the European Society for Medical Oncology (ESMO) Meeting

Arcus Biosciences, Inc. (NYSE:RCUS), a clinical-stage biopharmaceutical company focused on creating innovative cancer therapies, today announced that the Company will be presenting updated data from the ongoing Phase 1 dose-escalation trials of AB928, a potential best-in-class dual antagonist of adenosine receptors A_2aR and A_2bR, in a poster display session at the 2019 European Society for Medical Oncology (ESMO) Annual Meeting taking place in Barcelona, Spain from September 27-October 1, 2019.

Poster presentation details

Title: Phase 1 evaluation of AB928, a novel dual adenosine receptor antagonist, combined with chemotherapy or AB122 (anti-PD-1) in patients (pts) with advanced malignancies
Presentation Number: 1206P
Session Name: Poster Display Session
Date and Time: Monday, September 30, 12:00 p.m. - 1:00 p.m. Central European Summer Time (CEST)
Location: Poster Area (Hall 4), Fira Gran Via, Barcelona, Spain

A copy of the poster will be available on the "Publications" section of the Arcus website at www.arcusbio.com.

About AB928

AB928 is a dual antagonist of adenosine receptors A_2aR and A_2bR designed to block adenosine-mediated impairment of intra-tumoral immune cells, mainly lymphocytes (CD8+ T cells and NK cells) and myeloid cells (dendritic cells, macrophages). Developed specifically for the oncology setting, AB928 achieves high penetration of tumor tissue, robust potency in the presence of high adenosine concentrations, and minimal shift in potency from non-specific protein binding. Among agents in the clinic, AB928 is the only antagonist of A_2bR, found on both myeloid cells and cancer cells. AB928 thereby uniquely blocks adenosine's immunosuppressive and cancer cell-intrinsic effects in the tumor microenvironment. AB928 has demonstrated a favorable safety profile with a variety of combination regimens and exhibits pharmacokinetics / pharmacodynamics consistent with once-daily dosing. AB928 is currently in several ongoing Phase 1/1b expansion trials across multiple indications.

About AB122

AB122 is a fully human IgG4 antibody that potently and selectively blocks PD-1. The biochemical, biological and preclinical properties of AB122 have been shown to be similar to those of marketed anti-PD-1 antibodies. The Company is evaluating AB122 both as monotherapy and in combination as a core component for the Company's intra-portfolio combinations. AB122 is progressing into a Phase 1b biomarker-selected trial across advanced solid tumors in collaboration with Strata Oncology utilizing Strata's precision drug development platform and proprietary biomarkers. AB122 is also in Phase 1/1b expansion trials in combination with AB928, a dual antagonist of adenosine receptors A_2aR and A_2bR, in combination with AB154, its anti-TIGIT antibody, and in combination with AB680, its small-molecule CD73 inhibitor, plus chemotherapy.

About Arcus Biosciences

Arcus Biosciences is a clinical-stage biopharmaceutical company focused on creating innovative cancer therapies. Arcus has four programs in the clinic targeting important oncology/immuno-oncology pathways: (1) AB928, a dual antagonist of adenosine receptors A_2aR and A_2bR, being evaluated in several Phase 1/1b trials in combination with multiple regimens across a range of tumor types, (2) AB680, a small molecule inhibitor of CD73 progressing into a Phase 1/1b pancreatic cancer trial, (3) AB122, an anti-PD-1 antibody progressing into a biomarker-selected tumor-agnostic Phase 1b trial, and (4) AB154, an anti-TIGIT antibody being evaluated in combination with AB122. Arcus has extensive in-house expertise in medicinal chemistry, immunology, biochemistry, pharmacology and structural biology. Utilizing these unique capabilities, Arcus has developed a robust and active early-stage discovery effort focused on small-molecule pipeline expansion. For more information about Arcus Biosciences, please visit www.arcusbio.com.