ABSTRACT
In June 2022, the FDA extended the indication for lisocabtagene maraleucel (liso-cel) to include adults with large B-cell lymphoma (LBCL) who have refractory disease or relapse within 12 months of first-line chemoimmunotherapy (CIT), as well as transplant-ineligible adults with refractory disease or relapse after first-line CIT. Two clinical trials evaluating a single infusion of liso-cel preceded by lymphodepleting chemotherapy supported the second-line indications. TRANSFORM is a randomized, phase 3, open-label trial comparing liso-cel with standard second-line therapy, including planned autologous hematopoietic stem cell transplantation (HSCT), in 184 transplant-eligible patients. On interim analysis, event-free survival (EFS) by independent review committee (IRC) assessment was statistically significantly improved for the liso-cel arm, with a stratified hazard ratio of 0.34 [95% confidence interval (CI), 0.22-0.51; P < 0.0001]; the estimated median EFS was 10.1 months in the liso-cel arm versus 2.3 months in the control arm. PILOT is a single-arm phase 2 trial of second-line liso-cel in patients who were transplant-ineligible due to age or comorbidities but had adequate organ function for chimeric antigen receptor (CAR) T-cell therapy. Among 61 patients who received liso-cel (median age, 74 years), the IRC-assessed complete response rate was 54% (95% CI, 41-67). Among patients achieving complete response, the estimated 1-year rate of continued response was 68% (95% CI, 45-83). Of the 268 patients combined who received liso-cel as second-line therapy for LBCL, cytokine release syndrome occurred in 45% (Grade 3, 1.3%) and CAR T-cell-associated neurologic toxicities occurred in 27% (Grade 3, 7%), warranting a continued risk evaluation and mitigation strategy.
Subject(s)
Drug Approval , Immunotherapy, Adoptive , Lymphoma, Large B-Cell, Diffuse , United States Food and Drug Administration , Humans , United States , Immunotherapy, Adoptive/methods , Immunotherapy, Adoptive/adverse effects , Lymphoma, Large B-Cell, Diffuse/drug therapy , Lymphoma, Large B-Cell, Diffuse/therapy , Aged , Male , Female , Middle Aged , Adult , Hematopoietic Stem Cell Transplantation/adverse effects , Hematopoietic Stem Cell Transplantation/methods , Biological Products/therapeutic useABSTRACT
Obinutuzumab is a novel glycoengineered Type-II CD20 monoclonal antibody. CD20 is expressed in approximately 100% of children and adolescents with Burkitt lymphoma (BL) and 40% with precursor B-cell acute lymphoblastic leukaemia (pre-B-ALL). We evaluated the anti-tumour activity of obinutuzumab versus rituximab against rituximab-resistant (Raji 4RH) and -sensitive (Raji) BL and pre-B-ALL (U698-M) cells in vitro and in human BL or Pre-B-ALL xenografted mice. We demonstrated that obinutuzumab compared to rituximab significantly enhanced cell death against Raji 35·6 ± 3·1% vs. 25·1 ± 2·0%, (P = 0·001), Raji4RH 19·7 ± 2·2% vs. 7·9 ± 1·5% (P = 0·001) and U-698-M 47·3 ± 4·9% vs. 23·2 ± 0·5% (P = 0·001), respectively. Obinutuzumab versus rituximab also induced a significant increase in antibody-dependent cellular cytotoxicity (ADCC) with K562-IL15-41BBL expanded NK cells against Raji 73·8 ± 8·1% vs. 56·81 ± 4·6% (P = 0·001), Raji-4RH 40·0 ± 1·6% vs. 0·5 ± 1·1% (P = 0·001) and U-698-M 70·0 ± 1·6% vs. 45·5 ± 0·1% (P = 0·001), respectively. Overall survival in tumour xenografted mice receiving 30 mg/kg of obinutuzumab was significantly increased when compared to those receiving 30 mg/kg of rituximab in BL; Raji (P = 0·05), Raji4RH (P = 0·02) and U698-M (P = 0·03), respectively. These preclinical data suggest obinutuzumab is significantly superior to rituximab in inducing cell death, ADCC and against rituximab-sensitive/-resistant BL and pre-B-ALL xenografted mice. Taken together, these preclinical results provide evidence to suggest that future investigation of obinutuzumab is warranted in patients with relapsed/refractory CD20(+) BL and/or pre-B-ALL.
