Seoul St. Mary's Hospital launches cell therapy trial to prevent relapse in high-risk lymphoma patients

Seoul St. Mary's Hospital is launching a clinical research program to test the effectiveness of autologous immune cell therapy in high-risk lymphoma patients who remain at elevated risk of relapse even after achieving complete remission.

The hospital announced Wednesday that a research team led by Professor Min Ki-joon of the Department of Hematology at its Blood Cancer Center has been selected for the Ministry of Health and Welfare's 2026 Second Advanced Regenerative Medicine Clinical Research Activation Support Project.

The team will begin a clinical trial in October targeting patients with high-risk diffuse large B-cell lymphoma (DLBCL) to prevent disease relapse.

Seoul St. Mary's Hospital will serve as the lead research institution overseeing the entire study. The trial is a multi-center, prospective, randomized controlled study spanning 21 months with a budget of about 2.9 billion won ($2.1 million). Seoul National University Hospital and Ulsan University Hospital will participate as co-research institutions.

Diffuse large B-cell lymphoma is the most common subtype of non-Hodgkin lymphoma. Even when patients achieve complete remission — meaning no cancer cells are detectable after immunochemotherapy — roughly 30 percent of high-risk patients experience relapse within two years.

No established standard maintenance therapy currently exists to prevent such relapse. The central aim of this research is to find a new treatment strategy that can reduce the risk of recurrence in high-risk patients who have no standard treatment options after achieving complete remission.

The therapy the team seeks to validate is autologous cytokine-induced killer cell (CIK) treatment, which uses the patient's own immune cells.

CIK cells recognize stress proteins on the surface of cancer cells and secrete substances that destroy them. The research team expects this approach to suppress relapse by reducing residual microscopic cancer cells that may remain in the body after chemotherapy.

The treatment involves collecting immune cells from the patient's peripheral blood, activating and expanding them at a Good Manufacturing Practice (GMP) cell manufacturing facility, and then re-administering them in repeated doses. Because the therapy uses the patient's own immune cells, it carries a reduced risk of immune rejection.

The team previously reported on the safety and potential for relapse suppression of CIK cell therapy following autologous hematopoietic stem cell transplantation in a prospective clinical trial involving relapsed high-risk lymphoma patients. This new study expands the scope to high-risk DLBCL patients and will compare efficacy and safety against a standard observation group.

The trial will enroll 120 participants — 60 in the treatment group and 60 in the control group — assigned randomly to one of the two groups. Research data will be managed and analyzed by a separate contract research organization, and a safety monitoring committee will also be established.

The primary endpoint is the two-year progression-free survival rate following treatment. The team will also assess progression-free survival at six and 12 months, overall survival, relapse rates and immunological changes to comprehensively evaluate the therapy's efficacy and safety.

"Patients with high-risk DLBCL carry significant anxiety about relapse even after reaching complete remission, yet effective maintenance strategies to prevent it remain lacking," said Min Ki-joon, professor of hematology at Seoul St. Mary's Hospital. "Through this research, we aim to scientifically verify whether autologous CIK cell therapy can reduce the risk of relapse and develop it into a new treatment strategy."