Verismo Therapeutics Presents Preclinical Data at SITC 2026 Demonstrating Enhanced Tumor Control and Reduced Cytokine Release with SynKIR™-110 KIR-CAR Compared to Conventional CAR T

SynKIR™-110 demonstrated faster tumor control with approximately 10-fold lower IFNγ and 30-fold lower TNFα and IL-2 production compared to CD28-based single-chain CAR T in preclinical models

Preclinical in vivo data showed reduced exhaustion of tumor-infiltrating SynKIR™-110 T cells and no accumulation in healthy lung tissue compared to conventional single-chain CAR T designs

In vitro data showed reductions in T cell exhaustion, off-target proliferation, and toxicity with SynKIR™-110

PHILADELPHIA, Nov. 3, 2026 /PRNewswire/ -- Verismo Therapeutics, a clinical-stage CAR T cell therapy company pioneering a novel multi-chain KIR-CAR platform technology, today announced new preclinical data demonstrating enhanced anti-tumor activity, reduced cytokine release, and lower T cell exhaustion with SynKIR™-110 with reduced off-target activity compared to conventional single-chain CAR T designs. The data will be presented at the Society for Immunotherapy of Cancer (SITC) 41st Annual Meeting in Phoenix, Arizona (Abstract 253). The study evaluated SynKIR™-110 against CD28- and 4-1BB-based single-chain CAR T cells in preclinical mesothelioma xenograft models.

Poster Presentation Details

Title: Mesothelin-targeted Multi-Chain Killer Immunoglobulin Receptor (KIR)-based CAR T Reduces Exhaustion, Cytokine Release, and Enhances Safety Profile in vivo vs CD28 or 41BB single-chain CAR T
Presenter: Nora Yucel, Ph.D., Verismo Therapeutics
Session: Cellular Therapies — Chimeric Antigen Receptors
Session Date and Time: Friday, November 6, 2026 — 10 a.m.–2 p.m., 5–7 p.m. MT
Abstract Number: 253
Location: Phoenix Convention Center, Phoenix, Arizona
Full Abstract: https://www.sitcancer.org/2026/abstracts/titles-and-publications

In head-to-head comparisons, SynKIR™-110 achieved the fastest tumor control among the three CAR T designs with low cytokine production, while CD28-based single-chain CAR T cells produced approximately 10-fold higher IFNγ and 30-fold higher TNFα and IL-2 levels. Tumor-infiltrating SynKIR™-110 CD8 T cells also demonstrated reduced expression of exhaustion markers TIM3, LAG3, and PD1 compared to both single-chain comparators. Additionally, while both single-chain CAR T groups showed off-target activity in vitro and accumulation of CD8 CAR T cells in healthy lung tissue in vivo, no such effects were observed in SynKIR™-110-treated animals.

"These preclinical head-to-head findings reinforce the mechanistic rationale behind the multi-chain KIR-CAR platform — that separating antigen binding from T cell activation can meaningfully reduce tonic signaling and non-specific off-target activity associated with conventional single-chain CAR T designs, without compromising antitumor control," said Laura Johnson, Ph.D., Chief Scientific Officer and Chief Operating Officer of Verismo Therapeutics. "Seeing SynKIR™-110 deliver the fastest tumor control among the three CAR T architectures tested, with substantially lower cytokine production versus CD28-based single-chain CAR T, reduced T cell exhaustion markers compared with both single-chain comparators, and no off-target accumulation in healthy lung tissue, supports the differentiated safety and efficacy profile we are now evaluating in the ongoing STAR-101 clinical trial in patients with mesothelin-expressing solid tumors."

SynKIR™-110 is currently being evaluated in the ongoing Phase 1 STAR-101 clinical trial (NCT05568680) in patients with advanced mesothelin-expressing solid tumors, including mesothelioma, ovarian cancer, and cholangiocarcinoma. Initial clinical data presented at AACR 2026 showed a favorable safety profile in nine patients across the first three dose-escalation cohorts, with no dose-limiting toxicities, no Grade 3 or higher cytokine release syndrome, and no immune effector cell-associated neurotoxicity syndrome (ICANS) observed, while also demonstrating tumor reduction. SynKIR™-110 has received Orphan Drug and Fast Track designations from the U.S. Food and Drug Administration for mesothelioma. Dose escalation remains ongoing to determine the recommended Phase 2 dose.

About the KIR-CAR Platform

The KIR-CAR platform is a multi-chain T cell therapy that has shown highly effective solid tumor treatment in otherwise CAR-resistant animal models with hard-to-treat tumors. Using NK cell-derived killer immunoglobulin-like receptor (KIR) and DAP12 to split the target binding and T cell activation signals provides a novel paired immune-receptor activation that is independent from CD3 signaling and does not require additional co-stimulation. KIR-CAR enables sustained cell receptor expression in T cells, and induces deeper, more durable tumor treatments. Together, this multi-chain cell signaling platform provides the potential to deliver effective patient treatments by minimizing the background activation and early T cell exhaustion observed in conventional single-chain CAR T therapy, with potential to treat patients with both solid and hematologic tumors.

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 specifically developed 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

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:
Peter Collins
TogoRun
p.collins@togorun.com
908-499-1200

Investor Relations:
Pavel Aprelev, Ph.D.
Verismo Therapeutics
Pavel.Aprelev@verismotherapeutics.com

SOURCE Verismo Therapeutics