Verismo Therapeutics Shares Positive Preclinical Data at ASH 2025 Comparing SynKIR™-310 With Conventional CAR T

SynKIR™-310 achieved greater tumor control at lower doses with reduced cytokines in vivo, compared to CD19-targeted CAR T cells analogous to tisagenlecleucel.

PHILADELPHIA, Dec. 9, 2025 /PRNewswire/ -- Verismo Therapeutics, a clinical-stage CAR T company developing the novel KIR-CAR platform, today presented new preclinical data for SynKIR™-310, a CD19-targeting KIR-CAR T cell therapy, at the American Society of Hematology (ASH) Annual Meeting 2025. The presentation highlights key findings demonstrating that SynKIR™-310 achieved earlier tumor regression with deeper anti-tumor control and reduced cytokine levels compared to CD19-targeting conventional CAR T therapies.

Dr. Megan Blair, Scientist at Verismo Therapeutics presented "SynKIR™-310 Split-Signaling Based KIR-CAR T Cell Therapy Achieves Faster and Deeper Anti-B Cell Tumor Efficacy with Reduced Cytokine Levels" in poster format, demonstrating SynKIR™-310 anti-tumor activity outperformed conventional CAR T currently used in B cell cancers, with potential for fewer side-effects through reduced cytokine production.

Key Findings:

• Faster and Deeper Tumor Control:  In immunocompromised NSG mice with high B cell tumor (NALM6) burden, low doses of SynKIR™-310 worked faster and eliminated more tumor than tisagenlecleucel analog FMC63-41BBζ CAR T which showed significantly lower anti-tumor activity.
• Improved Anti-Tumor Activity Is Driven by KIR-CAR Signaling: Direct comparisons of SynKIR™-310 (DS191-KIR-CAR), FMC63-KIR-CAR, and FMC63-41BBζ CAR T cells showed that KIR-CAR signaling, and not CD19-targeting binder, was responsible for superior tumor control versus the conventional FMC63-41BBζ CAR/tisagenlecleucel analog.
• More Potent Tumor Control With Less Cytokine Release In Vivo: In the NALM6 mouse model, SynKIR™-310 T cells produced substantially lower levels of IFNγ, TNFα and IL-2 cytokines than FMC63-41BBζ CAR T, indicating that SynKIR™-310 achieved deeper tumor control with reduced systemic cytokines.

"Current approved CD19 CAR T therapies have transformed treatment for patients with B-cell cancers, although many still experience some toxicity from cytokine release syndrome. Even with this therapy, about half of patients have disease progression within a year, at least in part attributed to early T cell exhaustion or loss of function" said Dr. Laura Johnson, CSO/COO of Verismo Therapeutics. "These new data suggest that SynKIR™-310's novel KIR-CAR signaling design may promote earlier tumor control that is stronger and more durable, with potentially reduced risk of cytokine-induced toxicity, supporting its ongoing clinical evaluation in patients with relapsed or refractory B cell leukemias or lymphomas."

SynKIR™-310 is currently being evaluated in a Phase 1 clinical trial (NCT06544265) for patients with relapsed/refractory B-NHL, including those who have previously received CD19 CAR T therapies. SynKIR™-310 leverages Verismo's KIR-CAR split-signaling platform, which is designed to preserve T cell functionality and reduce exhaustion compared to conventional single-chain CAR T constructs.

About Verismo Therapeutics

Verismo Therapeutics, a subsidiary of HLB Innovation, is a pioneer in multi-chain KIR-CAR technology, with assets SynKIR™-110 (NCT05568680) and SynKIR™-310 (NCT06544265) currently in Phase 1 clinical trials. Verismo is the only company developing the KIR-CAR platform, using a modified NK cell-derived receptor and DAP12 pairing, designed to improve T cell functional persistence and reduce exhaustion, resulting in improved efficacy against challenging tumors. The KIR-CAR platform technology was developed specifically to address areas of high unmet medical need, including advanced solid tumors and B cell associated disorders and malignancies. For more information, visit: www.verismotherapeutics.com

About the KIR-CAR Platform

The KIR-CAR platform is a multi-chain CAR T cell therapy that has shown highly effective prolonged solid tumor treatment in otherwise CAR-resistant preclinical animal models with challenging tumor microenvironments.  Using NK cell derived KIR and DAP12 split-signaling provides a novel paired activation that is independent from CD3 signaling, and does not require 41BB/CD28 co-stimulation KIR-CAR enables sustained chimeric receptor expression with improved long-term CAR T cell function and decreased T cell exhaustion. This results in CAR T cell resistance to tumor immunosuppression, prolonged functional persistence and improved tumor elimination. Together, this platform provides the potential for improving CAR T treatment in both solid and hematologic tumors.

Forward Looking Statements

This press release contains forward-looking statements, including, but are not limited to, those statements regarding our expectations for the timing, progress, and results of clinical trials; potential regulatory approvals; anticipated benefits, safety, and efficacy of our product candidates; our product development strategies; and other statements that are not historical facts. These forward-looking statements are based on our current expectations and are subject to numerous risks and uncertainties that could cause actual outcomes to differ materially. Important factors that could cause actual results to differ include, among others, risks related to clinical trials, regulatory processes, market acceptance, financial projections, and our ability to successfully develop and commercialize our product candidates. Forward-looking statements in this release represent our beliefs and assumptions only as of the date hereof, and we expressly disclaim any obligation to update these statements as new information becomes available, except as required by law.

Media Contact:
Verismo Therapeutics
Pavel Aprelev, Ph.D.
[email protected]

SOURCE Verismo Therapeutics