ALC following BCMA CAR-T cell infusion in relapsed/refractory multiple myeloma
Saldarriaga MM, Pan D, Unkenholz C, et al. Absolute Lymphocyte Count After BCMA CAR-T Therapy Is a Predictor of Response and Outcomes in Relapsed Multiple Myeloma. Blood Advances. 2024; (doi: 10.1182/bloodadvances.2023012470).
Researchers have found that absolute lymphocyte count (ALC) following BCMA-directed chimeric antigen receptor (CAR) T-cell treatment can help predict which patients with relapsed/refractory multiple myeloma (MM) are likely to respond. An assessment of ALC in 156 patients who received ciltacabtagene autoleucel and idecabtagene vicleucel revealed that levels <0.5 x103/uL at 15 days post-infusion correlated to lack of response. These patients are considered a high-risk population, likely to experience early disease progression and abbreviated progression-free survival (PFS). Researchers also observed that levels >1.0 x103/uL predicted sustained response, but the greatest effect was documented with higher maximum ALC (ALCmax) during the first 15 days after treatment. Patients with ALCmax >1.0 x103/uL demonstrated superior depth of response, PFS, and duration of response. However, ALCmax also was associated with development of cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome.