Gagelmann N, Wulf GG, Duell J, et al. Hematopoietic Stem Cell Boost for Persistent Neutropenia After CAR-T Cell Therapy: A GLA/DRST Study. Blood Advances. 2022; (doi: 10.1182/bloodadvances.2022008042).
Administering an early or prophylactic hematopoietic stem cell boost (HSCB) improved outcomes for patients who experienced moderate to severe neutropenia after chimeric antigen receptor (CAR)-T cell therapy, new research shows. The study included 31 patients who were treated for sustained severe neutropenia of grade 4 (<0.5 x109/l), sustained moderate neutropenia (≤1.5 x109/l) and high risk of infection, or neutrophil count ≤2.0 x109/l and active infection. There was a 43-day median interval between CAR-T cell therapy and HSCB. The median absolute neutrophil count at the time of HSCB was 0.2, and the median neutropenia duration before HSCB was 38 days. Overall, 84% (26) of the patients showed recovery or sustained neutrophil improvement within a median of 9 days. The duration of prior neutropenia was significantly associated with response time. All of the patients who did not respond died within a year of receiving the HSCB. The one-year overall survival rate was 59%, with significant differences seen between patients who had neutropenia ≤38 days (85%) prior to HSCB and those who had neutropenia >38 days