OneChain’s CAR-T therapy OC-1 shows encouraging interim results in aggressive blood cancer

OneChain Immunotherapeutics announced promising interim results from its ongoing clinical trial evaluating its CAR-T therapy OC-1 in patients with relapsed or refractory T-cell acute lymphoblastic leukaemia/lymphoma (T-ALL/T-LL), a rare and aggressive blood cancer a ecting both children and adults. The data were presented at the 2026 Congress of the European Hematology Association (EHA), one of the leading scientific meetings in hematology worldwide.

These findings come from the Phase 1 study, which is intended to assess the safety and tolerability of OC-1, initial clinical e icacy, and help determine the appropriate dose levels.

The results showed promising early signs of activity in patients whose disease had returned or stopped responding after one or more previous treatments, patients with very limited remaining options. Most evaluable patients within the first two dose levels responded to treatment, with some of them achieving a complete response. OC-1 also showed a manageable safety profile in this early stage of development, with side e ects generally consistent with those seen with CAR-T cell therapies and no severe infections reported in treated patients.

The ongoing Phase 1 trial (EU CT Number 2024-514591-40-00) is being conducted at Hospital Sant Joan de Déu and Hospital Clínic Barcelona and continues to recruit patients as the study advances through higher dose levels. The trial is designed to further evaluate the safety and clinical activity of OC-1 in both paediatric and adult patients.

Addressing a high unmet need in T-cell malignancies

T-cell acute lymphoblastic leukaemia/lymphoma is a rare and aggressive blood cancer that can a ect both children and adults. Although many patients respond to initial treatment, outcomes are devastatingly poor when the disease relapses or becomes resistant to therapy. Patients in this setting often have very limited options, underscoring the need for new therapeutic approaches.

While CAR-T cell therapy has transformed treatment for some blood cancers, progress in T-cell malignancies has been slower, due to important scientific and manufacturing hurdles. These interim results represent an important and significant step forward in advancing new treatment options for patients facing this particularly challenging disease of high unmet medical need.

“For patients with relapsed or refractory T-cell leukaemia or lymphoma, treatment options are extremely limited. These interim results suggest that this new CAR-T cell therapy could o er a new opportunity for patients facing a very poor prognosis.” States Dr Susana Rives, a Principal Investigator in the study at the Pediatric Cancer Center Barcelona (PCCB) of the Hospital Sant Joan de Déu de Barcelona. “The CARxALL trial a first in human trial, so safety is of the utmost importance. Among the patients infused, toxicities have been manageable, with no deaths attributed to the experimental treatment", added Dr Núria Martínez-Cibrian, the second Principal Investigator of the clinical trial, at the Hematology and Hemotherapy department of the Hospital Clinic of Barcelona.

About OneChain Immunotherapeutics

OneChain Immunotherapeutics is a clinical-stage biotechnology company focused on the development of next-generation immunotherapy treatments for cancer. Founded in Barcelona in 2020 as a spin-o of the Josep Carreras Leukaemia Research Institute, together with ICREA and Dr. Pablo Menéndez, the company builds on pioneering research in cell therapy and cancer immunology.

OneChain is supported by a strong group of institutional and financial partners, including Invivo Partners, CDTI, Nara Capital, Clave Capital and the Josep Carreras Leukaemia Foundation.

The company is advancing a pipeline of innovative cell therapy programmes for haematological malignancies and solid tumours. Its lead programme, OC-1, is a CAR-T cell therapy currently in clinical development for T-cell acute lymphoblastic leukaemia/lymphoma. OneChain is also developing a novel next-generation in vivo CAR-T platform of exceptional specificity, able to simultaneously engineer multiple immune cell types directly in the body of patients; OC-1d, a dual CAR-T approach for T-cell acute lymphoblastic leukaemia; and a dual CAR-T cell therapy for multiple solid tumours.

The Project CPP2021-008508 is funded by MICIU/AEI /10.13039/501100011033 and by the European Union NextGenerationEU/ PRTR.

More information about the product and the ongoing trial can be found here.

Link to the abstract here