A Phase 1 clinical trial that uses natural T-cells to target multiple antigens for the treatment of blood and bone marrow cancers is showing promise, say a group of researchers from Children’s National Health System in Washington, D.C.
The researchers presented their findings last week in Orlando, Florida, at the latest BMT Tandem meeting — which combines the annual meetings of the Center for International Blood & Marrow Transplant Research and the American Society for Blood and Marrow Transplantation.
The data brings new hope to a cell therapy approach that could harness the immune system’s cancer-killing potential to beat cancers in cases where stem cell transplantation has failed.
The Phase 1 RESOLVE trial, funded by the National Institutes of Health (NIH) and the Leukemia Lymphoma Society, is a multicenter, dose-finding study designed to evaluate the safety and effectiveness of multi tumor-associated antigen specific lymphocytes (TAA-L) as a novel treatment for patients with blood cancers.
The study enrolled patients diagnosed with one of four types of tumor — acute myeloid leukemia, myelodysplastic syndromes, B-cell acute lymphoblastic leukemia and Hodgkin lymphoma — who had relapsed after receiving stem cell transplants.
Results revealed that 78 percent of patients responded to TAA-L treatment, including 44 percent complete remissions and 38 percent partial responses.
Toxicity was also limited, with no reported cases of graft-versus-host disease — a condition in which the donor’s immune cells attacks the patient’s own tissues — or other autoimmune-mediated toxicity. There were also no observations of cytokine release syndrome or neurotoxicity associated with the TAA-L approach.
Preliminary observations of this trial also suggest that ex vivo manufactured TAA-L can be successfully isolated and expanded to clinically relevant numbers, frozen and later safely infused into patients after relapse episodes.
“These initial findings suggest that non-genetically engineered antigen-specific lymphocytes can be isolated, expanded and adoptively transferred to severely ill patients with active disease and positively impact tumor regression,” the study’s co-author, Catherine Bollard, MD, said in a press release.
“We are encouraged by the promise of these data, which support similar efforts to exploit the immunotherapeutic potential of the natural T-cell repertoire,” added Bollard, director of the Program for Cell Enhancement and Technologies for Immunotherapy at Children’s National, which collaborated with Johns Hopkins University and Baylor College of Medicine on the investigation.