ZUMA-1 demonstrated a high rate of durable response and a manageable safety profile with axicabtagene ciloleucel (axi-cel), an anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, in patients with refractory large B-cell lymphoma. As previously reported, prespecified clinical covariates for secondary end point analysis were not clearly predictive of efficacy; these included Eastern Cooperative Oncology Group performance status (0 vs 1), age, disease subtype, disease stage, and International Prognostic Index score. We interrogated covariates included in the statistical analysis plan and an extensive panel of biomarkers according to an expanded translational biomarker plan. Univariable and multivariable analyses indicated that rapid CAR T-cell expansion commensurate with pretreatment tumor burden (influenced by product T-cell fitness), the number of CD8 and CCR7+CD45RA+ T cells infused, and host systemic inflammation, were the most significant determining factors for durable response. Key parameters differentially associated with clinical efficacy and toxicities, with both theoretical and practical implications for optimizing CAR T-cell therapy. This trial was registered at www.clinicaltrials.gov as #NCT02348216.

ZUMA-3 is a phase 1/2 study evaluating KTE-X19, an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, in adult relapsed/refractory (R/R) B-ALL. We report the phase 1 results. Following fludarabine/cyclophosphamide lymphodepletion, patients received a single infusion of KTE-X19 at 2, 1, or 0.5×106 cells/kg. The rate of dose-limiting toxicities (DLTs) within 28 days following KTE-X19 infusion was the primary endpoint. KTE-X19 was manufactured for 54 enrolled patients and administered to 45 (median age: 46 years [range, 18-77]). No DLTs occurred in the DLT-evaluable cohort. Grade ≥3 cytokine release syndrome (CRS) and neurologic events (NE) occurred in 31% and 38% of patients, respectively. To optimize the benefit-risk ratio, revised adverse event (AE) management for CRS and NE (earlier steroid use for NE and tocilizumab only for CRS) was evaluated at 1×106 cells/kg KTE-X19. In the 9 patients treated under revised AE management, 33% had grade 3 CRS and 11% had grade 3 NE, with no grade 4/5 NE. The overall complete remission rate correlated with CAR T-cell expansion and was 83% in patients treated with 1×106 cells/kg and 69% in all patients. Minimal residual disease was undetectable in all responding patients. At 22.1 months (range, 7.1-36.1) median follow-up, the median duration of remission was 17.6 months (95% CI, 5.8-17.6) in patients treated with 1×106 cells/kg and 14.5 months (95% CI, 5.8-18.1) in all patients. KTE-X19 treatment provided a high response rate and tolerable safety in adults with R/R B-ALL. Phase 2 is ongoing at 1×106 cells/kg with revised AE management.

In phase 2 of ZUMA-1, a single-arm, multicenter, registrational trial, axicabtagene ciloleucel (axi-cel) autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy demonstrated durable responses at 2 years in patients with refractory large B-cell lymphoma (LBCL). Here, we aimed to assess survival and safety in ZUMA-1 after 5 years of follow-up. Eligible adults with refractory LBCL (diffuse large B-cell lymphoma, primary mediastinal B-cell lymphoma, and transformed follicular lymphoma) received lymphodepleting chemotherapy followed by axi-cel infusion targeted at 2×106 cells/kg. Investigator-assessed response, updated survival, safety, and pharmacokinetic outcomes were assessed in treated patients. The objective response rate in the 101 treated patients was 83% (58% complete response rate), and with a median follow-up of 63.1 months, responses were ongoing at data cutoff in 31%. Median overall survival (OS) was 25.8 months and the estimated 5-year OS rate was 42.6%. Disease-specific survival (excluding deaths unrelated to disease progression) estimated at 5 years was 51.0%. No new serious adverse events or deaths related to axi-cel were observed after additional follow-up. Peripheral blood B cells were detectable in all evaluable patients at 3 years with polyclonal B-cell recovery in 91%. Ongoing responses at 60 months were associated with early CAR T-cell expansion. In conclusion, this 5-year follow-up analysis of ZUMA-1 demonstrates sustained overall and disease-specific survival, with no new safety signals in patients with refractory LBCL. Protracted B-cell aplasia was not required for durable responses. These findings support the curative potential of axi-cel in a subset of patients with aggressive B-cell lymphomas. ClinicalTrials.gov, number NCT02348216

Neelapu and colleagues report a post hoc subgroup analysis from the ZUMA-1 trial of chimeric antigen receptor T-cell therapy for relapsed or refractory diffuse large B cell lymphoma. In comparison with younger patients, those ≥65 years old have similar rates of complete response and durable response at 2 years, but higher rates of neurological toxicity.

The SCHOLAR-1 international retrospective study highlighted poor clinical outcomes and survival among patients with refractory large B-cell lymphoma (LBCL) treated with conventional chemotherapy. Axicabtagene ciloleucel (axi-cel), an autologous anti-CD19 chimeric antigen receptor T-cell therapy, demonstrated durable responses in patients with refractory LBCL in the pivotal phase 1/2 ZUMA-1 study (NCT02348216). Here, we compared SCHOLAR-1 with the 2 year outcomes of ZUMA-1. Prior to comparison of clinical outcomes, propensity scoring (based on a broad set of prognostic covariates) was used to create balance between ZUMA-1 and SCHOLAR-1 patients. In the pivotal phase 2 portion of ZUMA-1, 101 patients received axi-cel and were evaluable for response and survival. In SCHOLAR-1, 434 and 424 patients were evaluable for response and survival, respectively. ZUMA-1 patients were more heavily pretreated than SCHOLAR-1 patients. The median follow-up was 27.1 months in ZUMA-1. The objective response rate and complete response rate were 83% and 54% in ZUMA 1 vs 34% and 12% in SCHOLAR-1, respectively. The 2-year survival rate was 54% in ZUMA-1 and 20% in SCHOLAR-1, and a 73% reduction in the risk of death was observed in ZUMA-1 vs SCHOLAR-1. These results were consistent with those of an additional standardization analysis in which strata were limited to 2 prognostic factors (refractory categorization and presence/absence of stem cell transplant after refractoriness to chemotherapy) to conserve sample size. Despite the limitations of a nonrandomized analysis, these results indicate that axi-cel produces durable responses and a substantial survival benefit versus non-CAR T-cell salvage regimens for patients with refractory LBCL.