Bal, Susan

Patients with plasma cell leukemia (PCL) are generally excluded from pivotal T-cell redirecting bispecific antibody (BsAb) trials. We evaluated real-world outcomes in a multicenter retrospective study of 122 patients with primary or secondary PCL across 15 academic centers, categorized as 'active' (≥5% circulating plasma cells within 30 days of BsAb initiation) or 'historical'. In a heavily pretreated population, patients received teclistamab (37%), elranatamab (11%), talquetamab as a line of therapy (Tal LOT, 42%), or talquetamab as bridging therapy to CAR-T (Tal Bridge, 11%). Cytokine release syndrome (CRS) was grade 1-2 in 56% and grade 3-4 in 4%, whereas neurotoxicity was grade 1-2 in 16% and grade 3-4 in 5%. Among 110 evaluable patients, the overall response rate (ORR) was 55%, including 61% with Tal LOT, 58% with Tal Bridge, 46% with elranatamab, and 33% with teclistamab. With a median follow-up of 8.3 months, talquetamab demonstrated superior survival. Tal LOT showed a median progression-free survival (mPFS) of 5.5 months and a median overall survival (mOS) of 11.5 months, and both were unreached in the Tal Bridge cohort. In contrast, teclistamab and elranatamab showed a mPFS of 1.2 and 1.6 months and mOS of 8.1 and 3.6 months, respectively (P=0.007, P=0.023). In active PCL, Tal LOT achieved mPFS/mOS of 6.9/12.2 months versus 0.7/1.4 months with teclistamab and 1.0/3.1 months with elranatamab, respectively (P<0.001, P=0.002). Multivariable analysis associated active PCL with worse survival and Tal LOT with improved outcomes. BsAbs were safe in PCL, with talquetamab showing superior outcomes compared with BCMA-directed BsAbs.

Abstract Recent therapeutic advances, including bispecific antibodies (bsAbs), have improved outcomes for patients with relapsed/refractory multiple myeloma (RRMM). However, early mortality (EM) remains a significant challenge, even in the era of novel immunotherapies. We conducted a multicenter, retrospective analysis of real-world patients with RRMM treated with commercial bsAbs to evaluate the incidence and causes of EM. Between May 2022 and June 2025, a total of 441 patients were treated across 7 countries. EM, defined as death within 12 months of therapy initiation, occurred in 148 patients (34%), with a median time from bsAb initiation to death of 2.87 months (interquartile range, 1.38-6.85). The leading cause of EM was progressive disease (72%), followed by infection (13%); regardless of the cause of death, 82% had active disease at the time of death. Our findings highlight that despite encouraging efficacy, EM remains high among real-world bsAb recipients, emphasizing the need for improved disease control strategies and supportive care interventions.

This guideline has been updated. This ASCO Living Guideline is reviewed on an eight-week cycle. Please see the online dynamic version for the latest updates. ASCO Guidelines provide recommendations with comprehensive review and analyses of the relevant literature for each recommendation, following the guideline development process as outlined in the ASCO Guidelines Methodology Manual . ASCO Guidelines follow the ASCO Conflict of Interest Policy for Clinical Practice Guidelines . Clinical Practice Guidelines and other guidance (“Guidance”) provided by ASCO is not a comprehensive or definitive guide to treatment options. It is intended for voluntary use by clinicians and should be used in conjunction with independent professional judgment. Guidance may not be applicable to all patients, interventions, diseases or stages of diseases. Guidance is based on review and analysis of relevant literature, and is not intended as a statement of the standard of care. ASCO does not endorse third-party drugs, devices, services, or therapies and assumes no responsibility for any harm arising from or related to the use of this information. See complete disclaimer in Appendix 1 and Appendix 2 (online only) for more . PURPOSE To provide updated guidance regarding the therapy for multiple myeloma. METHODS ASCO and Ontario Health (Cancer Care Ontario) convened a joint Expert Panel and conducted an updated systematic review of the literature. RESULTS The updated review identified a total of 161 relevant randomized trials. UPDATED RECOMMENDATIONS Daratumumab therapy may be offered to patients with high-risk smoldering myeloma. Quadruplet therapy with daratumumab or isatuximab, combined with bortezomib, lenalidomide, and dexamethasone, should be offered as initial therapy for transplant eligible patients. They should also be offered at least lenalidomide maintenance, with or without daratumumab, carfilzomib, and/or dexamethasone. Quadruplet therapy with daratumumab or isatuximab, combined with bortezomib, lenalidomide, and dexamethasone, should be offered as therapy for suitable transplant-ineligible patients. Patients with relapsed or refractory multiple myeloma should be offered triplet therapy or T-cell redirecting therapies according to a set of recommended principles. Additional information is available at www.asco.org/hematologic-malignancies-guidelines .