Preclinical data supports the development of JTX-8064 as a novel immunotherapy to reprogram immune-suppressive macrophages and enhance anti-tumor immunity

CAMBRIDGE, MA, USA I April 03, 2019 I Jounce Therapeutics, Inc. (NASDAQ: JNCE), a clinical-stage company focused on the discovery and development of novel cancer immunotherapies and predictive biomarkers, today reported data on JTX-8064, its first tumor-associated macrophage program, at the 2019 American Association for Cancer Research (AACR) Annual Meeting in Atlanta, GA. The poster presentation includes preclinical data demonstrating the immunotherapeutic properties of JTX-8064 to reprogram immune-suppressive macrophages within the tumor microenvironment.

“Today, we presented the characterization of JTX-8064 and the preclinical data for this novel product candidate, demonstrating its potential in re-programming tumor-associated macrophages within the tumor microenvironment to enhance anti-tumor immunity. We believe that LILRB2 functions as an immune checkpoint for macrophages and have demonstrated differentiation from other macrophage-directed approaches,” said Elizabeth Trehu, M.D., chief medical officer of Jounce Therapeutics. “New insights from our Translational Science Platform continue to inform JTX-8064 development and we expect to file an Investigational New Drug application and initiate a Phase 1 clinical trial later this year.”

In a poster titled “Preclinical evaluation of JTX-8064, an anti-LILRB2 antagonist antibody, for reprogramming tumor-associated macrophages,” Jounce researchers describe the preclinical evaluation of JTX-8064 including:

  • JTX-8064 is a specific and potent antagonist antibody of LILRB2 (leukocyte immunoglobulin like receptor B2; ILT4)
  • LILRB2 binds to its ligands (classical MHC I molecules [e.g. HLA-A, HLA-B] and non-classical MHC I molecules [e.g. HLA-G]) and maintains an immuno-suppressive state in macrophages. JTX-8064 blocks ligand binding to LILRB2 and induces an immune activating state in macrophages that may lead to enhancement of the anti-tumor immune response
  • Inhibiting LILRB2 induces pro-inflammatory cytokine secretion and a unique transcriptional profile suggestive of an M1-like shift in human macrophages, which is distinct from macrophage-targeted mAbs CSF1R and TIM-3

The poster is available on the “Our Approach” section of the Jounce Therapeutics website at www.jouncetx.com.

About JTX-8064
JTX-8064 is an anti-Leukocyte Immunoglobulin Like Receptor B2 (LILRB2) antibody and is the first candidate to emerge from Jounce’s Translational Science Platform efforts that focuses on tumor-associated macrophages. Preclinical data presented at the 2019 AACR Annual Meeting supports the development of JTX-8064 as a novel immunotherapy to reprogram immune-suppressive macrophages and enhance anti-tumor immunity. JTX-8064 is currently in IND-enabling activities and Jounce anticipates filing an IND and initiating a Phase 1 clinical trial for JTX-8064 in 2019.

About Jounce Therapeutics
Jounce Therapeutics, Inc. is a clinical-stage immunotherapy company dedicated to transforming the treatment of cancer by developing therapies that enable the immune system to attack tumors and provide long lasting benefits to patients. Through the use of its Translational Science Platform, Jounce first focuses on specific cell types within the human tumor microenvironment to prioritize targets, and then identifies related biomarkers designed to match the right immunotherapy to the right patient. Jounce has three development-stage programs: its two clinical product candidates, vopratelimab, a monoclonal antibody that binds to and activates ICOS, and JTX-4014, a monoclonal antibody that binds to PD-1 and for potential use in combination with Jounce’s pipeline of future product candidates, and JTX-8064, a monoclonal antibody that binds to LILRB2 that is currently in the IND-enabling phase. For more information, please visit www.jouncetx.com.

SOURCE: Jounce Therapeutics