Ibrutinib improves the efficacy of anti-CD19-CAR T-cell therapy in patients with refractory non-Hodgkin lymphoma

The efficacy and side effects of the second-time humanized CD19 chimeric antigen receptor (CD19-CAR) T-cell therapy after unsuccessful first-time anti-CD19-CAR T-cell therapy and subsequent ibrutinib salvage treatment were observed in patients with refractory B-cell lymphoma. In our study, 3 patients with refractory mantle cell lymphoma (MCL) and 4 patients with refractory follicular lymphoma (FL) reached stable disease (SD), partial remission (PR), or progression of disease (PD) after first-time humanized anti-CD19-CAR T-cell therapy. They received ibrutinib as a salvage treatment and kept an SD in the following 7-16 mo, but their disease progressed again during ibrutinib salvage treatment. All 7 patients received a second-time humanized anti-CD19-CAR T-cell therapy, which was the same as their first-time anti-CD19-CAR T-cell therapy. In total, 3 MCL patients and 3 FL patients reached complete response (CR) with the second-time anti-CD19-CAR T-cell therapy combined with ibrutinib, whereas 1 FL patient reached PR. There were no differences in the transduction efficiency and proliferation between the 2 instances of anti-CD19-CAR T-cell therapy. However, the second-time anti-CD19-CAR T-cell therapy led to higher peaks of anti-CD19-CAR T cells and anti-CD19-CAR gene copies, but also to higher grades of cytokine release syndrome (CRS) and more serious hematological toxicity. The successful outcome of the second-time anti-CD19-CAR T-cell therapy might suggest that the previous ibrutinib treatment improved the activities of anti-CD19-CAR T cells.