A simple blood test that measures lymphocyte counts may predict whether patients with relapsed multiple myeloma are going to respond well to chimeric antigen receptor (CAR) T-cell immunotherapy, according to research published by Saldarriaga et al in Blood Advances. The study found that patients who had an increase in absolute lymphocyte count (ALC) during the first 15 days after receiving a B-cell maturation antigen (BCMA)-targeted CAR T-cell infusion had a higher chance of a complete response and better progression-free survival than patients with a lower ALC at day 15.
“This highly active FDA-approved treatment is widely used, but until now there’s really been nothing to tell us whether BCMA CAR T-cell therapy is going to work or not after the patient has received this personalized therapy,” said lead author Mateo Mejia Saldarriaga, MD, Assistant Professor of Medicine in the Division of Hematology and Medical Oncology at Weill Cornell Medicine and an oncologist at NewYork-Presbyterian/Weill Cornell Medical Center. “Using ALC as a marker for how well a patient will respond could better guide treatment.”
Study Details
Based on previous observations, the researchers analyzed data from 156 patients treated at Weill Cornell Medicine, NewYork-Presbyterian, Columbia University, or Icahn School of Medicine at Mount Sinai who had received BCMA-targeted CAR T-cell therapy between 2017 and 2023 for relapsed multiple myeloma. Patient ALCs were taken 5 days before treatment started and for the first 15 days of BCMA-targeted CAR T-cell therapy.
Patients with a higher ALC at day 15 had significantly better response to treatment, with their cancer under control for an average of 30 months, whereas those who had a lower ALC averaged 6 months of progression-free survival.
“This was a multicenter collaborative study between three big institutions in New York that ensures the diversity of the patient population and decreases the chance of bias,” said Mark Bustoros, MD, Assistant Professor of Medicine at Weill Cornell Medicine and corresponding author of the study. “We were able to confirm that high ALC is an independent predictive marker of disease progression after accounting for various factors like age, previous treatments, and high-risk disease features.”
Laboratory studies showed that a higher ALC was associated with the BCMA-targeted CAR T cells thriving in the body—growing and multiplying—which may be a reason the cancer was kept in check.
“If doctors can identify patients who are more likely to have a poor response to BCMA[-targeted] CAR T-cell therapy, other treatments can be explored or given earlier,” said Dr. Mejia Saldarriaga.
Researchers also want to determine how they can create strategies to enhance the activity of BCMA-targeted CAR T-cell therapy in patients who have lower ALC. “The treatment has been a great tool, but there is still room for improvement,” he added.
Disclosure: For full disclosures of the study authors, visit ashpublications.org/bloodadvances.
