Jae Park, MD, a hematologic oncologist and assistant attending physician at Memorial Sloan Kettering Cancer Center (MSK), will present findings about the durability of CAR T cell therapy response in patients with relapsed B-cell acute lymphoblastic leukemia (B-ALL) at the American Association for Cancer Research (AACR) Annual Meeting. This research has been selected to be featured in the meeting’s press program. The AACR is the oldest and largest professional organization dedicated to advancing cancer research, and the press program highlights cancer research that a panel of AACR experts considers the most significant of the year and deserving of media attention. Dr. Park will present his findings at the Update, Novel Indication, and New-Immuno-Oncology Clinical Trials Minisymposium at on April 3.
Although most patients with relapsed B-ALL experienced complete response after treatment with CD19-specific CAR T cell immunotherapy, pre-treatment disease burden impacted the durability of the responses and long-term survival, according to data from a clinical trial. Dr. Park and colleagues analyzed data from a recently completed phase I clinical trial that tested CD19-specific CAR T cell therapy in adults with relapsed B-ALL to identify those who benefited the most from this therapy. All of the 51 adult patients in the trial had relapsed or refractory B-ALL after one or more conventional multiagent chemotherapies. The researchers measured disease burden prior to CAR T cell therapy and found that despite high initial response rates in all groups, patients with minimal residual disease (MRD) had significantly longer survival compared with patients who received CAR T cells at the time of morphologic disease. The researchers also found that long-term survival did not improve for patients who had a hematopoietic stem cell transplant after CAR T cell therapy.
“There is a critical need to develop effective therapy for adult patients with relapsed or refractory B-ALL,” explained Dr. Park. “These findings suggest that incorporation of CD19-specific CAR T cells at the time of MRD following first-line chemotherapy, rather than waiting until they relapse morphologically, may maximize the durability of CAR T cell–mediated remissions and survival and can potentially spare high-risk patients from undergoing a hematopoietic stem cell transplant.”
The team is now performing more comprehensive analysis of T cell products and host characteristics to identify factors that can explain the different long-term outcome of MRD and morphologic disease patients.
“In recent years, we have witnessed a successful translation of basic immunology that has led to a rise in promising immunotherapy treatments for cancer,” explained Dr. Park. “CAR T cell therapy, which was pioneered at MSK, has seen a number of stunning achievements in a short amount of time. We are encouraged by this progress and eager to continue our work with these ‘living therapies’ in order to provide new, better, and safer treatment options to patients.”