Surface Oncology Presents New Preclinical Data on SRF114, a fully human anti-CCR8 antibody, at the AACR Annual Meeting 2023

– New in vivo data show SRF114 promotes a pro-inflammatory tumor microenvironment resulting in robust antitumor activity in mouse models –

CAMBRIDGE, Mass., April 18, 2023 (GLOBE NEWSWIRE) -- Surface Oncology (Nasdaq: SURF), a clinical-stage immuno-oncology company developing next-generation immunotherapies that target the tumor microenvironment, today announced the presentation of new preclinical data for SRF114, a fully human anti-CCR8 antibody, at the American Association for Cancer Research (AACR) Annual Meeting 2023 in Orlando, Florida. The data will be presented in a poster session (abstract #5125) being held today.

“We are highly encouraged by these new preclinical data which indicate that therapeutic depletion of CCR8 positive tumor infiltrating Tregs results in robust anti-tumorigenic activity in both checkpoint inhibition-resistant and checkpoint inhibition-susceptible tumor models,” said Vito Palombella, PhD, chief scientific officer, Surface Oncology. “These data bolster our belief that SRF114 holds the potential to become a best-in-class anti-CCR8 treatment and further support our ongoing Phase 1 clinical investigation of SRF114 in patients with advanced solid tumors.”

Summary of key data

• In human CCR8 knock-in mice, SRF114, a fully human antibody targeting human CCR8, conferred robust anti-tumor activity and reshaped the tumor microenvironment towards a proinflammatory milieu.
• In different in vivo models, SRF114 monotherapy or treatment with a murine surrogate antibody promoted expansion of CD8⁺ effector T cells and increased the production of pro-inflammatory molecules including IFNγ, TNFα, and granzyme A in a checkpoint-resistant tumor model.
• Anti-CCR8 therapy resulted in depletion of tumor Tregs without impacting peripheral lymphoid Treg cell populations and led to increases in the levels of co-stimulatory molecules CD80 and CD86 in a subset of tumor myeloid cells.
• Anti-CCR8 and anti-PD-1 combination therapy increased tumor immune cell infiltration, cytokine production and improved overall survival in a checkpoint inhibitor resistant melanoma model.

Poster Session Information
Title: Depletion of CCR8+ tumor Treg cells with SRF114 or anti-CCR8 therapy promotes robust antitumor activity and reshapes the tumor microenvironment toward a more pro-inflammatory milieu
Abstract number: 5125
Session category: Immunology
Session title: Combination Immunotherapies 2
Session date and time: Tuesday, April 18, 2023, from 1:30 p.m. to 5:00 p.m. ET

A copy of the poster will be available on the Posters & Publications page of the company’s website following the presentation.

About SRF114
SRF114 is a fully human, afucosylated anti-CCR8 antibody designed to preferentially deplete CCR8⁺ Treg cells within the tumor microenvironment. In preclinical studies, Surface Oncology has shown that SRF114 induces antibody-dependent cellular cytotoxicity (ADCC) and/or antibody-dependent cellular phagocytosis (ADCP) pathways to deplete intratumoral Treg cells. In addition, SRF114 reduced tumor growth in murine models. These findings support the advancement of SRF114 as a therapeutic candidate that holds the potential to drive anti-tumor immunity in patients.

About Surface Oncology
Surface Oncology is an immuno-oncology company developing next-generation antibody therapies focused on the tumor microenvironment. Its pipeline includes two wholly-owned programs; SRF388, a Phase 2 program which targets IL-27, and SRF114 which selectively depletes regulatory T cells in the tumor microenvironment via targeting CCR8. In addition, Surface has two partnerships with major pharmaceutical companies: a collaboration with Novartis targeting CD73 (NZV930; Phase 1) and a collaboration with GlaxoSmithKline targeting PVRIG (GSK4381562, formerly SRF813; Phase 1). Surface’s novel, investigational cancer immunotherapies are designed to achieve a clinically meaningful and sustained anti-tumor response and may be used alone or in combination with other therapies. For more information, please visit www.surfaceoncology.com.

Contact
Scott Young
Vice President, Investor Relations and Corporate Communications
+1 617 865 3250
syoung@surfaceoncology.com