GC Cell Doses First Patient in Phase 1b Trial of CAR-NK Therapy

GC Cell (144510.KQ), the cell and gene therapy affiliate of GC Group, is accelerating clinical development of a next-generation CAR-NK cell therapy aimed at hard-to-treat blood cancers. Based on safety and early efficacy data from its Phase 1a trial, the company plans to determine the optimal dose in Phase 1b and expand development into a global registrational trial.

GC Cell said on the 7th that its drug candidate GCC2005 (CD5 CAR-NK) had completed dosing of subjects in the dose-escalation stage of its Phase 1a trial and had begun a Phase 1b trial, with dosing of the first subject now complete.

The Phase 1b trial will optimize the dosing regimen and dose level of GCC2005 and enroll additional patients in the optimal dose group to strengthen safety and efficacy data. On that basis, the company plans to determine the recommended Phase 2 dose (RP2D), which will serve as the foundation for a future global registrational trial.

The trial targets patients with NK/T-cell lymphoma who have relapsed after standard treatment or have not responded to it. To speed up clinical development, GC Cell plans to add major domestic trial sites, expanding to as many as six institutions.

For NK/T-cell lymphoma, chemotherapy known as CHOP has served as the first-line standard of care for decades, but its effectiveness is limited. Second-line treatment is also used only in a limited way in certain subtypes, leaving a high unmet need for new treatment options. Worldwide, new cases of T-cell lymphoma are estimated at about 20,000 a year.

GC Cell is currently running its Phase 1 trial mainly in patients who have received multiple prior lines of therapy. In future development, the company is also reviewing a move into second-line treatment, an earlier stage of care, given the high unmet need among relapsed and refractory patients.

GCC2005 is a fourth-generation allogeneic CAR-NK cell therapy that targets CD5, which is predominantly expressed in T-cell lymphoma. It is designed to co-express interleukin-15 (IL-15) to improve the persistence of the immune cells in the body, and GC Cell is aiming to develop it as a first-in-class global therapy.

GC Cell assessed the safety and preliminary efficacy of GCC2005 during the dose-escalation stage of the Phase 1a trial. The results were presented orally at major international conferences last year, including the American Society of Hematology (ASH) meeting. At the recent International Congress of Blood Marrow Transplantation (ICBMT 2026), the company also disclosed a long-term follow-up case in which a patient reached complete response (CR) after a low-dose administration and maintained it for more than 18 months.

"After confirming the potential of GCC2005 as a next-generation cell therapy in the Phase 1a trial, we have now completed dosing of the first patient in the Phase 1b trial," GC Cell Chief Executive Won Sung-yong said. "We will move the Phase 1b trial forward quickly and prepare for a global registrational trial so that we can demonstrate the value of this candidate as an innovative therapy in T-cell lymphoma, a field with high unmet medical need."