Verismo Therapeutics' Initial Clinical Data from STAR-101 Phase 1 Trial of SynKIR™-110 KIR-CAR Presented at AACR 2026 Plenary Session

• Early clinical data show a favorable safety profile and dose-dependent efficacy signals across initial dose level cohorts 1 - 3 in advanced solid tumors for potential first of its kind multi-chain KIR-CAR living medicine
• Preliminary data suggest on-tumor target biologic activity with increased cell persistence at increased dose levels
• No dose-limiting toxicities were observed; dose escalation continues to determine a recommended Phase 2 dose

PHILADELPHIA, April 20, 2026 /PRNewswire/ -- Verismo Therapeutics, a clinical-stage CAR T cell therapy company pioneering a novel multichain KIR-CAR platform technology, today announced the first clinical results from its ongoing Phase 1 STAR-101 clinical trial (NCT05568680) evaluating SynKIR™-110 KIR-CAR living medicine in patients with advanced mesothelin-expressing solid tumors, including ovarian cancer, mesothelioma, and cholangiocarcinoma. These late-breaking data were presented during the Clinical Trial Plenary session 3 at the American Association for Cancer Research (AACR) Annual Meeting 2026 in San Diego, CA (Abstract CT 104).

"We are excited to share Verismo's first presentation of clinical data evaluating our multi-chain SynKIR™-110 KIR-CAR candidate, showing a positive safety profile, dose-dependent efficacy signals, and no dose-limiting toxicities," said Laura Johnson, Ph.D., Chief Operating Officer and Chief Scientific Officer of Verismo Therapeutics. "These data represent an important milestone for Verismo's KIR-CAR platform, which is designed to combine the best of natural killer and T cells to fight cancer and may provide a more durable response than current single-chain CAR T therapies that are prone to exhaustion in difficult-to-treat solid tumor microenvironments."

Janos L. Tanyi, M.D., Ph.D., Principal Investigator for STAR-101 and Professor at the Perelman School of Medicine at the University of Pennsylvania (Penn), presented the data from nine patients treated across three dose-escalation cohorts. SynKIR™-110 in dose level cohorts 1 through 3 showed a favorable safety profile, with no dose-limiting toxicities, no high-grade (Gr3+) cytokine release syndrome (CRS), and no immune effector cell-associated neurotoxicity syndrome (ICANS) events observed.

The initial data showed on-target biologic activity based on KIR-CAR T cell expansion and persistence in patients and serum cytokine changes after SynKIR™-110 infusion. Anti-tumor activity was observed at increased dose levels, with 1 of 3 patients at dose level 3 achieving a partial response per RECIST criteria that was ongoing after 3+ months at the interim data cut-off for this dataset, which was September 2025. The trial remains ongoing, with continued enrollment to evaluate safety and determine the recommended Phase 2 dose.

"These data are significant because patients with mesothelin-expressing solid tumors continue to face significant and urgent needs for better treatments," said Dr. Tanyi, who is an associate professor of Obstetrics and Gynecology at Penn. "The safety profile we have observed, including low grade (Gr 1-2) CRS in only 3 of 9 patients, and no neurotoxicity, combined with early signs of clinical activity, support continued investigation of this novel approach in patients with solid tumors."

About SynKIR™-110 KIR-CAR and the STAR-101 Clinical Trial

SynKIR™-110 KIR-CAR is an investigational autologous engineered cell therapy developed using Verismo's KIR-CAR platform. This approach utilizes a multi-chain, split-signaling architecture derived from natural killer cells, designed to drive long-term anti-tumor T cell function without T cell exhaustion. By keeping antigen recognition separate from T cell activation, the multi-chain architecture is intended to sustain T cell activity even in challenging solid-tumor microenvironments.

The STAR-101 clinical trial is a first-in-human, multicenter, open-label Phase 1 study in the U.S., designed to evaluate the safety, feasibility, and preliminary efficacy of SynKIR™-110 in patients with advanced mesothelin-expressing solid tumors, including ovarian cancer, mesothelioma, and cholangiocarcinoma. These target indications are associated with poor prognosis and remain areas of high unmet medical need. The STAR-101 trial follows a dose-escalation design with an expansion cohort at the recommended Phase 2 dose. Patient recruitment and dose escalation in the trial is ongoing.

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 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 works independent of co-stimulation. KIR-CAR enables sustained cell receptor expression in T cells, and induces deeper, more durable tumor treatments. Together, our multi-chain cell signaling platform provides the potential to deliver effective patient treatments by eliminating the constant background signaling and early T cell exhaustion observed in conventional single-chain CAR T therapy, with potential to treat 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.

Editor's Note: The University of Pennsylvania (Penn) has licensed certain Penn-owned intellectual property to Verismo. Penn's Perelman School of Medicine receives funding for research and development of certain Verismo products. Penn may receive future financial benefits related to the licensing of certain Penn intellectual property to Verismo.

Investor Relations:
Pavel Aprelev, Ph.D.
Verismo Therapeutics
[email protected]

Media Contact:
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SOURCE Verismo Therapeutics