Abstract 6327: Impact of G-CSF on safety and efficacy of CAR T-cell therapy in non-Hodgkin lymphoma

Abstract Introduction: Chimeric antigen receptor T-cell (CAR-T) therapy is an established treatment modality for the management of refractory and/or relapsed non-Hodgkin lymphoma (NHL). Despite restrictions on granulocyte colony-stimulating factor (G-CSF) use in registration clinical trials due to potential worsening of cytokine release syndrome (CRS), G-CSF is often prescribed for neutrophil recovery post-CAR-T in clinical practice. We conducted a retrospective study to assess the association between G-CSF use and the safety and efficacy of CAR-T. Methods: Following Institutional Review Board approval, we retrospectively analyzed NHL patients receiving commercial CD19-targeted CAR-T across Mayo Clinic sites (Arizona, Florida, and Minnesota) between October 2017 and May 2023. Demographics, labs, and post CAR-T events were collected. Electronic medical records were reviewed for G-CSF exposure within Day 1 - 100 post-CAR T. Differences by G-CSF status were examined using a Chi-square test and Kruskal Wallis tests. Hazard ratios (HR) and 95% confidence intervals (CI) for overall survival (OS) were calculated using Cox model. Results: Among 270 CAR-T patients; 106 received G-CSF within 30 days and 164 did not. Median age was 56.9 with G-CSF and 58.3 without G-CSF. Most were male (75.2% G-CSF, 62.6% no G-CSF). Diffuse large B cell lymphoma was the predominant NHL subtype (67.0% G-CSF, 65.2% no G-CSF). G-CSF within 30 days was not associated with reduced incidence of neutropenic fever (11.7% G-CSF vs 9.9% no G-CSF, p = 0.6593) or documented infection (22.1% vs 18.3%, p = 0.4439). G-CSF correlated with decreased profound neutropenia duration (ANC < 100 μL, 0 vs 2 days, p < 0.0001) and incidence within 30 days ( 31.7% vs 60.4%, p < 0.0001) as well as incidence of protracted profound neutropenia (> 7 days, 3.8% vs 22.8%, p < 0.0001). G-CSF was associated with a higher incidence of cytopenias between days 30 -100: severe neutropenia (ANC < 500/uL, 28.8% vs 15.2%, p = 0.0075), severe anemia (Hb < 8 g/dL, 21% vs 9.7%, p = 0.0114), and severe thrombocytopenia (Plt < 50 g/L, 35.2% vs 20.9%, p = 0.0099). Logistic regression analysis showed that none of the examined covariates, including prior autologous stem cell transplant, ECOG PS score, and receipt of bridging therapy, were associated with severe neutropenia likelihood. G-CSF was associated with a higher CRS incidence (89.6% vs 79.9%, p = 0.0343), but grade 3 CRS or higher (4.7% vs 3.7%, p = 0.6675) was no different. No difference in complete response rates (66% vs 61.1%, p = 0.4707) or 2-year OS (p = 0.523) was observed between the 2 groups. Conclusion: G-CSF within 30 days was associated with reduced duration and incidence of profound neutropenia without a significant impact on incidence of neutropenic fever or documented infections. There was a signal of association between G-CSF and increased incidence of low-grade CRS and delayed cytopenias (day 30-100) that warrants confirmation in larger studies. Citation Format: Lay She Ng, Claire I. Yee, Radhika Bansal, Mohamed A. Kharfan-Dabaja, Grzegorz S. Nowakowski, Allison C. Rosenthal, Javier Munoz, Januario Castro, Wern Lynn Ng, Hemant S. Murthy, Yi Lin, Matthew R. Buras, Madiha Iqbal, Yucai Wang, Talal Hilal. Impact of G-CSF on safety and efficacy of CAR T-cell therapy in non-Hodgkin lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6327.