The prognostic value of CAR-hematox in predicting toxic events in patients with relapsed refractory B cell lymphoma receiving 7x19 CAR-T treatment

Abstract Background: The 7×19 CAR-T cell therapy has demonstrated significant efficacy in relapsed/refractory B-cell lymphoma (R/R B-NHL), yet treatment-related toxicities—including cytokine release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), and hematological toxicity—remain clinical challenges. The CAR-HEMATOTOX (HT) score, a prognostic model based on inflammatory markers and baseline blood cell counts, has not been fully validated for predicting outcomes in 7×19 CAR-T treatment. This study evaluates the predictive value of HT scores in predicting adverse effects and survival outcomes among patients receiving 7×19 CAR-T therapy. Method: This study retrospectively analyzed 39 patients with relapsed/refractory B-cell lymphoma (R/R B-NHL) treated with 7×19 CAR-T therapy. Patients were classified into low-risk (≤1 point) and high-risk groups based on the HT score. The incidence and severity of CRS, ICANS, and hematological toxicities (e.g., neutropenia, thrombocytopenia) were evaluated between the two groups. The correlation between HT scores and progression-free survival (PFS) and overall survival (OS) was also analyzed. Results: High-risk patients (n=13) were significantly more likely to experience grade 3 or higher hematological toxicity (100% vs. 30.77%, p<0.01) and severe CRS (15.38% vs. 11.54%, p=0.74)/ICANS (11.54% vs. 15.38%, p=0.72) compared to low-risk patients (n=26). The high-risk group also showed a higher incidence of grade 3 or greater delayed hematological toxicity (30.77% vs. 15.68%, p<0.01). Survival time in the high-risk group was median 19.8+9 months, while in the low-risk group it was median 20.2+10.1 months. The 24-month survival rate was 42% in the low-risk group versus 15% in the high-risk group. Conclusion: CAR-HEMATOTOX score can effectively predict long-term survival, hematological and non-hematological toxicity events after 7×19 CAR T treatment, and help to identify high-risk patients early and optimize supportive therapy strategies. Key words: CAR-T cell therapy; B cell lymphoma; CAR-HEMATOTOX score; treatment-related toxicity; prognostic model