ABCL-366: Mosunetuzumab (Mosun) Monotherapy for Elderly/Unfit Patients with First-Line Diffuse Large B-Cell Lymphoma (DLBCL) Continues to Show Promising Safety and Efficacy with Durable Complete Responses

Autor: Ron McCord, Adam J. Olszewski, Matthew S McKinney, Dariusz Woszczyk, Gila Sellam, Netanel A. Horowitz, Houston Holmes, Naseer Qayum, Carol O'Hear, Wojciech Jurczak, Itai Levi, Krzysztof Giannopoulos, Herbert Eradat, Abraham Avigdor, Uri Abadi, Yuying Xie, Mingzhu Zhou, Sunil Babu
Rok vydání: 2021
Předmět:
Zdroj: Clinical Lymphoma Myeloma and Leukemia. 21:S395-S396
ISSN: 2152-2650
DOI: 10.1016/s2152-2650(21)01896-6
Popis: Context Mosun, a full-length, humanized, IgG1 CD20×CD3 bispecific antibody, demonstrated efficacy/safety in relapsed/refractory DLBCL (NCT02500407; Schuster, et al. ASH 2019). The phase I/II multicenter GO40554 (NCT03677154) study showed similar results for elderly/unfit patients with first-line DLBCL intolerant of full-dose chemoimmunotherapy (CIT) (Olszewski, et al. ASH 2020). Objective To describe updated GO40554 study data. Methods Two safety-evaluation cohorts were assessed (Mosun 13.5 mg and 30 mg), then a 30 mg expansion phase. Patients were aged ≥80 years; 60–79 years with impairment in ≥1 activity of daily living (ADL); instrumental ADL; or impaired cardiac, renal, or liver function. Patients received optional pre-treatment with prednisone (+/– vincristine), then intravenous mosun in step-up doses on days (D)1 (1 mg), 8 (2 mg), and 15 (full-dose: 13.5/30 mg) of cycle (C)1, and full (C1D15) dose on D1 of each 21-day cycle for eight cycles, continuing for ≤17 cycles. Results As of January 15, 2021, 40 patients received mosun (13.5 mg safety cohort, n=8; 30 mg safety cohort, n=7; 30 mg expansion, n=25). Median age: 84 (range 67–100) years; 50% with Ann Arbor Stage III–IV, 80% with IPI score ≥2. Of 40 treated patients, 27 (67.5%) had ≥1 mosun-related adverse event (AE); 15 (37.5%) had a grade 3–4 AE. Most common treatment-emergent AE: cytokine release syndrome (CRS; n=9, 22.5%); five patients had neutropenia (12.5%). Six (15%) patients had grade 1 CRS per ASTCT (Lee, et al. Biol Blood Marrow Transplant 2019); three (7.5%) had grade 2 CRS, all managed with supportive care, fluids for hypotension, steroids, or low-flow oxygen, as required (no tocilizumab, vasopressors, high-flow oxygen, or intensive care). 14 (35%) patients discontinued due to progressive disease (PD). Overall response rate for efficacy-evaluable patients (n=31): 67.7%; complete response (CR) rate: 41.9%. Responses with 13.5 mg mosun: CR: 37.5%; PR: 37.5%; PD: 25%; with 30 mg mosun: CR: 43.5%; PR: 21.7%; stable disease/PD: 34.8%. Four durable responses were observed ≥12 months from start of therapy in 13 patients with CR (11 ongoing). Conclusions Mosun showed promising efficacy, including durable responses, and tolerable safety for elderly/unfit patients with 1L DLBCL; it should be further evaluated as a chemotherapy-free backbone for patients unable to tolerate standard CIT.
Databáze: OpenAIRE