Allogeneic transplant after failure of chimeric antigen receptor (CAR) T-cell therapy can be effective for patients with lymphoma, a retrospective study suggests.
Patients with relapsed/refractory large B-cell lymphoma (LBCL) who previously received anti-CD19 CAR T-cell therapy underwent allogeneic hematopoietic stem cell transplant (allo-HSCT) and had durable responses at 1 year, according to Joanna C. Zurko, MD, of the Medical College of Wisconsin in Milwaukee.
Dr Zurko noted that 1-year outcomes in this study were similar to outcomes seen with allo-HSCT for LBCL patients who have not received prior CAR T-cell therapy. She presented these results at the Tandem Meetings 2022.
Dr Zurko and colleagues evaluated allo-HSCT after CAR-T therapy in 88 patients with relapsed/refractory LBCL. The patients’ median age at transplant was 54 years (range, 19-72), 72% of patients were men, and 66% were White.
Most patients (59%) had de novo diffuse large B-cell lymphoma (DLBCL), 26% had transformed indolent DLBCL, 9.1% had primary mediastinal B-cell lymphoma, and 5.7% had high-grade B-cell lymphoma not otherwise specified.
Before CAR T-cell therapy, patients had received a median of 3 prior lines of therapy (range, 1-7), and 25% of patients had a prior autologous transplant. The CAR T-cell therapies patients received included axicabtagene ciloleucel (67%), lisocabtagene maraleucel (12%), tisagenlecleucel (5%), and investigational CAR-T therapy (16%).
The median time between CAR-T therapy and allo-HSCT was 8.4 months (range, 2.1-24.8 months). During this time, patients received a median of 1 line of therapy (range, 0-7).
Right before transplant, 51% of patients had achieved a complete response (CR), 25% had a partial response, and 24% had stable or progressive disease.
Most patients received non-myeloablative conditioning (77%). Donor types included matched unrelated (39%), haploidentical (30%), matched related (26%), mismatched unrelated (3%), and cord blood (2%).
The median follow-up after allo-HSCT was 15.0 months (range, 1-72 months). The cumulative incidence of neutrophil recovery was 94% at 28 days, and the cumulative incidence of platelet recovery was 85% at 100 days. One patient had graft failure.
At 100 days, the cumulative incidence of grade 2-4 acute graft-vs-host disease (GVHD) was 34%, and the incidence of grade 3-4 acute GVHD was 10%. At 1 year, 30% of patients had chronic GVHD.
The median progression-free survival (PFS) was 10 months, and the median overall survival (OS) was 21 months. The 1-year PFS rate was 45%, and the 1-year OS rate was 59%. The 1-year non-relapse mortality rate was 22%, and the rate of relapse or progression was 33%.
On multivariate analysis, inferior PFS was significantly associated with a higher number of treatment lines between CAR-T therapy and allo-HSCT as well as a lack of CR prior to allo-HSCT.
Inferior OS was significantly associated with both aforementioned factors as well as Hispanic ethnicity. Inferior non-relapse mortality was significantly associated with all 3 aforementioned factors as well as receiving a myeloablative conditioning regimen.
“Based on these findings, we believe that transplant-eligible patients, at least those who achieve a CR after CAR-T failure, should be considered for allogeneic transplant at this time,” Dr Zurko said.
She also emphasized the need for long-term follow-up to confirm the durable remission rate and curative potential of allo-HSCT after CAR-T failure.
Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
Zurko JC, Ramdial J, Ahmed S, et al. Allogeneic hematopoietic cell transplantation for relapsed/refractory large B-cell lymphoma after CAR T-cell therapy failure. Tandem Meetings 2022; April 23-26, 2022. Abstract 8.