Compass Therapeutics Presents Data Demonstrating Elimination of MHC Class I Negative Tumors in In Vivo Models at the 2024 American Association for Cancer Research (AACR) Annual Meeting

• Major Histocompatibility Complex Class I (MHC-I) negative tumors are refractory to immune-oncology therapies, including resistance to checkpoint blockers, due to the loss of the fundamental recognition of the tumor by CD8+ T-Cells, which drive the adaptive immune attack on the tumor.

• Immune responses were generated toward the MHC-I negative tumors by combining CTX-009 with CTX-471. This combination was surprisingly synergistic. The proposed mechanism for this effect suggests the involvement of NK-cells, which can generate potent cell killing independent of MHC-I.

• By blocking DLL4 and VEGF, CTX-009 may increase the trafficking and penetration of NK Cells into the tumor microenvironment where CTX-471 may augment the activity of these cells. This activity against the tumor does not require MHC-I integrity.

• The combination of CTX-009 and CTX-471 has the potential to be an effective therapeutic regimen in patients who have previously progressed on checkpoint blockers, such as anti-PD-1 and anti-PD-L1 antibodies.
  

BOSTON, April 09, 2024 (GLOBE NEWSWIRE) -- Compass Therapeutics, Inc. (Nasdaq: CMPX), a clinical-stage, oncology-focused biopharmaceutical company developing proprietary antibody-based therapeutics to treat multiple human diseases, today presents a poster on the combination of its bispecific antibody, CTX-009, and its agonistic anti-CD137 antibody, CTX-471, on anti-tumor activity in preclinical models at the 2024 American Association for Cancer Research (AACR) Annual Meeting taking place at the San Diego Convention Center in San Diego, California on April 9.

“We are very excited to see the anti-tumor activity of our bispecific DLL4/VEGF-A antibody, CTX-009, in multiple preclinical tumor models,” said Thomas Schuetz, MD, PhD, Co-Founder and President of Research & Development at Compass. “The post-Checkpoint Inhibitor (CPIs, either PD-1 or PD-L1) patient population is one of the most significant unmet medical needs in medical oncology today. When a tumor is MHC-I negative, it is effectively invisible to the immune system; however, importantly, in these models the combination of CTX-009 and CTX-471 eliminated tumors, suggesting that the combination of CTX-009 and CTX-471 could be considered as a viable alternative where previous immunotherapy has failed.”