Filgrastim Associations with CAR T-cell Therapy.

Little is known about the benefits and risks of myeloid growth factor administration following Chimeric Antigen Receptor (CAR) T-cell therapy for Diffuse Large B-cell Lymphoma (DLBCL). We present a retrospective analysis among 22 relapsed/refractory DLBCL patients who received CAR T-cell therapy with axicabtagene ciloleucel. Filgrastim was administered by physician discretion to 7 patients (31.8%), and the median duration of neutropenia following lymphodepleting therapy was significantly shorter for those patients who received filgrastim (5 days vs 15 days, p = 0.016). Five patients (22.7%) developed infection in the 30 days post-CAR T-cell therapy with 3 patients being grade 3 or higher. There was no difference in the incidence and severity of infection based on filgrastim use (p = 0.274, p = 0.138). Among the 7 patients that received filgrastim, 6 patients (85.7%) and 4 patients (57.1%) had evidence of cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS), respectively. Among the 15 patients that did not receive filgrastim, 8 patients (53.3%) and 7 patients (46.7%) had evidence of CRS and ICANS, respectively. There was no significant difference in the incidence of developing CRS or ICANS between the group of patients that received filgrastim and those that did not (p = 0.193, p = 0.647). However, there was a significant increase in the severity of CRS for patients that received filgrastim compared to those that did not (p = 0.042). Filgrastim administration following CAR T-cell therapy may lead to an increase in severity of CRS without decreasing infection rates.