Larrea, Carlos Fernández de

ABSTRACT Talquetamab is a GPRC5D × CD3 bispecific antibody approved for relapsed/refractory multiple myeloma (RRMM). This is the first real‐world study to comprehensively report muco‐cutaneous toxicities, infections, and efficacy of talquetamab in 151 patients across five countries with the longest follow‐up reported enabling better efficacy and toxicity estimates. The median age was 64 years; high‐risk cytogenetics were present in 42%; ECOG ≥ 2 in 22%; 12% had creatinine clearance < 30; and 55% would not have met MonumenTAL‐1 eligibility. Patients received a median of 6 prior lines of therapy, 53% were penta‐refractory, and 75% received prior BCMA therapy. Talquetamab was associated with skin toxicity in 39.7%, nail toxicity in 75.5%, dysgeusia in 60.4%, and oral toxicities in 62.9%, with grade ≥ 3 events uncommon (≤ 4%) and dose interruptions infrequent (9.6% for skin toxicity, 6.9% for dysgeusia, and 4.0% for oral toxicities). These findings underscore the need for improved supportive care for muco‐cutaneous toxicities. In multivariate analysis, only platelet count < 50 (HR 1.8, 95% CI 1.15–2.83) was associated with inferior PFS, while penta‐refractory status, absolute lymphocyte count < 0.4, and prior BCMA‐targeted therapy were not statistically significant. With a median follow‐up of 12.7 months, the overall response rate was 67.6%, median progression‐free survival was 7 months, and 12‐month overall survival was 65%. This study shows that talquetamab efficacy is maintained in a heavily pretreated real‐world population with high prior BCMA exposure and notable comorbidity burden.

Background Emerging evidence has demonstrated rare subacute to late neurological toxicities (NTs) after BCMA CAR T-cell therapy (CAR-T) in multiple myeloma (MM). These adverse events can be categorized as: 1) Parkinsonism (PD), 2) cranial nerve (CN) palsies, and 3) peripheral neuropathies/Guillan Barré syndrome (GBS). These toxicities can cause significant morbidity, but given their relative rarity in clinical trials, there is limited data regarding evaluation and treatment. To our knowledge, this is the largest and only global registry of delayed NTs after BCMA CAR-T. Methods We retrospectively established a registry of NTs via the Immune Therapy Working Committee of the International Myeloma Working Group (IMWG). We gathered data pertaining to demographics, MM characteristics, MM response, NT signs/symptoms, diagnostic workup, and treatment. Result A total of 52 patients with delayed neurotoxicity were included from 14 institutions and 6 countries; 92% received ciltacel, 4% idecel, and 4% investigational CAR-T. Median age at CAR-T infusion was 65 years; 69% were male and 88% were Caucasian. Median bone marrow plasma cell (PC) burden was 15% prior to CAR-T (range 0-95%). Patients received a median of 4 prior lines of therapy (LOT), with 67% progressing on last LOT. Seventeen percent had pre-existing neurological diagnoses (including stroke, epilepsy, migraines). We identified sixteen cases of PD (94% with movement disorder, 69% with cognitive impairment, 75% with personality changes), occurring at a median of 26 days (range: 15-87) after CAR-T. Ninety four percent had CRS (grade (G)1 50%, G2 38%, G3 6%, G4 0%), while 19% had ICANS (G1 13%, G2 6%, G3-G4 0%). Median peak absolute lymphocyte count (ALC) was 9.5 x 109/L, peak C-reactive protein (CRP) 60.9 mg/L, and peak ferritin 1893.5 ug/L within the first 30 days. Concurrently, 3 upper respiratory infections (URIs) and 2 low-level HHV7 in the cerebrospinal fluid (CSF) were detected. A median of 73% of T-cells in the CSF were CAR-T, based on a flow cytometry assay. Ten patients received steroids (median 19 days after symptoms, 70% partial response, 20% no response, 10% unknown), 2 received intrathecal (IT) methotrexate-based therapy (median 32 days after symptoms, 1 with no response, 1 unknown), 5 received intravenous (IV) cyclophosphamide (median 31 days after symptoms, 40% full response, 20% partial response, 40% no response), 4 received high-dose IVIG ≥1g/kg for one or more dose (50% partial response, 50% no response), and 6 received dopamine agonists. There were 37 CN palsies (76% CN7, 15% CN6, 7% CN5, 2% CN3), occurring at a median of 37.5 days (range: 7-482) after CAR-T. Eighty one percent had CRS (G1 68%, G2 14%, G3-G4 0%); 11% had G1 ICANS (G2-G4 0%). Median peak ALC was 4.1 x 109/L, CRP 25.4 mg/L, and ferritin 543 ug/L within the first 30 days. We identified 2 concurrent URIs, 4 CMV viremia (50% with viral load &gt;1500 IU/mL), 1 HHV6 viremia, and 1 HSV in the CSF. Thirty-two (86%) received steroids for a median duration of 12 days, 50% with full response, 3% with no response, and 47% with partial response (of which 43% had later full recovery without further intervention). One received IT methotrexate and another received IV cyclophosphamide without response. Thirteen (41%) received IVIG, of which 38% was high-dose IVIG. Four patients with CN palsies developed peripheral neuropathy/GBS. Eight patients (15%) in this cohort were not heavily pre-treated (≤1 prior LOT); 7 developed CN palsies (6 after ciltacel, 1 after investigational CAR-T) and 1 PD (after idecel). These patients had median &lt;5% PC; none had extramedullary disease. Median ALC was 4.14 x 109/L, CRP 33 mg/L, and ferritin 448.5 ug/L within the first 30 days. Conclusions Delayed NT requires prompt recognition, evaluation for alternative causes, and treatment. In our cohort, the majority of patients were male and Caucasian, suggesting that sex and race may impact the likelihood of developing NT. Individuals with PDs had greater inflammatory response (CRS, ALC, CRP, ferritin) compared to those with CN palsies. CN palsies responded to steroids and/or IVIG, whereas PD had at best partial response to steroids, prompting additional therapy. These toxicities notably did occur in less heavily pre-treated patients, perhaps driven by immune fitness and greater circulating T-cells rather than MM burden. At the time of the annual meeting, data will be updated with additional NTs from less heavily pre-treated patients.

Introduction: Waldenström macroglobulinemia (WM)remains incurable with current therapies. Treatment options for patients beyond initial therapy are limited, underscoring the need for new agents with novel mechanisms of action. Iopofosine I 131 is a novel radiopharmaceutical composed of a lipid raft-targeting phospholipid ether covalently bound to 131I, a beta-emitting radioisotope. Herein, we report the results of the CLOVER-WaM study [NCT02952508] in patients with previously treated WM. Methods: Eligible WM patients had received &gt;2 prior therapies and had symptomatic disease requiring therapy according to consensus recommendations for WM. Treatment consisted of 2 cycles of iopofosine I 131 administered at 15 mCi/m2 on days 1 and 15 of each 57-day cycle. Dose reduction to 10 mCi/m2 was allowed in the second cycle in patients with incomplete hematologic recovery or if the expected total dose exceeded 132 mCi. Supportive care with growth factors and transfusions was permitted per treating physician discretion. The primary endpoint was major response rate (MRR, defined as partial response or better) as determined by the modified VIth International Workshop on Waldenström Macroglobulinemia Response Criteria. Secondary endpoints included overall response rate (ORR), treatment-free survival (TFS), duration of response (DOR), and clinical benefit rate (CBR, defined as stable disease or better). Efficacy endpoints were assessed in the modified intent-to-treat (mITT) population, defined as all patients who received ≥60 mCi total administered dose of iopofosine I 131. MRR was analyzed with a 95% 2-sided confidence interval (CI) using the Clopper-Pearson interval method. In this population, MRR &gt;20% was considered statistically significant. Time-dependent efficacy endpoints were analyzed using the Kaplan-Meier method. Safety was evaluated using CTCAE v4.03 in patients who received &gt;1 dose of iopofosine I 131. The data cut-off for this analysis was May 31, 2024. Results: In 65 patients enrolled (safety population), the median age was 70 (range, 50-88) years; 48 (73.8%) were male, and 17 (26.2%) were female. Sixty-one (93.8%) were White, 1 (1.5%) was Black/African American, and 3 (4.6%) were other or unknown. Fifty-five patients met mITT criteria and were evaluable for efficacy. The median number of prior therapies was 4 (range, 2-15). Bruton's tyrosine kinase inhibitor (BTKi) exposure was noted in 39 (71%) patients, of whom 31 (56%) were BTKi-refractory. Sixteen (29%) patients had MYD88-wild type, and 5 (9%) had CXCR4-mutated disease. The MRR was 56.4% (95% CI, 42.3-69.7). ORR was 80%; among MYD88-wild type patients, ORR was 81%, and among post-BTKi patients, ORR was 72%. CBR was 98%. The median DOR and TFS were not reached at a median follow-up of 8.8 months, with an estimated 72% of responding patients remaining progression-free at 18 months. In the safety population, any-grade adverse events, regardless of causality, were reported in 57 (87%) patients. Grade 3 or higher treatment-emergent adverse events (TEAEs) occurring in &gt;10% of patients included thrombocytopenia (80%), neutropenia (69.2%), anemia (44.6%), lymphopenia (13.8%), infections (12.3%), and febrile neutropenia (10.8%). Adverse event-related death occurred in 1 patient due to bacterial sepsis. Conclusion: Iopofosine I 131 demonstrated durable efficacy in previously treated WM patients, with no current standard of care therapy. The treatment was well-tolerated with a manageable toxicity profile across broad biologic and clinical subgroups, irrespective of risk stratification. Based on the results of this trial, iopofosine I 131 shows promise as a novel treatment for WM patients.

Introduction: BCMA-directed CAR-T and Bispecific T-cell engager (BiTE) therapies have shown remarkable overall response rates in heavily pretreated patients with relapsed/refractory multiple myeloma (RRMM). This has led to the approval of idecabtagene vicleucel, ciltacabtagene autoleucel and teclistamab by the FDA, EMA and other regulatory agencies. We performed a global survey on accessibility, practice patterns, and toxicity management of commercially available CAR-T and BiTE therapies. Methods: An online survey was completed by clinicians attending the International Myeloma Society's Immune Effector Cell Therapies in Multiple Myeloma Workshop, in-person or virtually, made available for 30 days after the meeting held in March 2023, Boston, MA. Results: 87 clinicians from 16 countries completed the survey, most practicing in an academic practice (86%) and in an urban environment (89%). Sixty-four percent of the respondents practice in North America followed by Europe (25.3%) including Germany, United Kingdom, Ireland, Italy, Netherlands, Spain, France, Greece, and Cyprus, and 6.9% from Asia and 3.4% from Australia. Seventy-seven percent reported CAR-T cell therapy was approved in their country with 44.8% treating 1-5 patients and 14.9% treating &gt;5 patients per month; 67% reported BiTE therapy was approved in their country with 14.9% treating &gt;5 patients per month. Of evaluable responses (n = 40), 62% administered CAR-T therapy inpatient and 15% administered CAR-T therapy outpatient ≥ 50% of the time. Length of time between decision to treat with CAR-T therapy to infusion was 6-12 weeks for 42% of responders and &lt;6 weeks for only 20%. Most (75%) reported inpatient administration of BiTE therapy step-up dosing; 17.5% reported outpatient step-up dosing administered ≥ 50% of the time. Use of institutional or practice SOPs for CAR-T and BiTE therapy patient selection was reported by 85% and 58%, respectively, with the factors influencing SOP outlined in Table 1. Of available CAR-T therapies, 53% prefer cilta-cel and 23% reported CAR-T therapy preference depended most on patients' co-morbidities/frailty (89%), timing of next available apheresis (67%), age (56%), CNS disease (44%) and other factors. Maintenance therapy after CAR-T therapy was reportedly used by 25% and 5% of respondents in 1-10% and 11-50% of their patients, respectively, to “maintain level of response achieved” (50%) or “achieve a deeper level of response” (25%). About half (43%) of the respondents reported using an SOP or particular criteria for secondary Hemophagocytic Lympho-Histiocytosis/Macrophage Activation Syndrome/CAR-related-HLH (sHLH/MAS/CarHLH) management that varied between the use of ASTCT Working Group IEC associated HLH-like syndrome Criteria (47%) (Hines 2023), CARTOX HLH Criteria (24%) (Neelapu 2017) and HLH-2004 criteria (6%). Tocilizumab was used as cytokine release syndrome (CRS) prophylaxis only by one responder. Keppra neurologic prophylaxis was used by 47.5% and 15% of responders for CAR-T and BiTE therapy, respectively. Delayed neurotoxicity with CAR-T was reported in 1-5% of patients by 57.5% of responders and 6-10% of patients by 15% of responders; most common manifestations were other movement/neuromuscular disorder (62%), nerve palsy (55%), and Parkinsonism (45%). Infectious prophylaxis was used to protect against HSV (92.5%), PJP (90%), bacterial pathogens (55%), fungal pathogens (60%), and IVIG (77.5%). However, criteria for infectious prophylaxis use varies widely incorporating IgG levels, infectious history, CD4+ count, B-cell aplasia and cytopenias (48.1 - 88.9%). Most respondents (46.3 - 86.5%) reported completing an infectious work-up including CMV, EBV, Hep B/C, and HIV ( Table 2). Conclusions: Trends of CAR-T and BiTE therapy use and patterns of concurrent prophylactic and supportive care in MM vary widely among academic centers across the globe, demonstrating a need for further understanding of toxicity pathogenesis, toxicity management and consistent guidelines. This survey also demonstrates the great unmet need for access beyond urban centers among the international myeloma community. Prospective studies and claims data analysis should be utilized to evaluate the longitudinal cost of care, quality of life, duration of response and management of infectious disease, neurological or related complications of CAR-T and bispecific TCE therapies.

Abstract Background: Initial studies with venetoclax, a BCL-2 inhibitor, alone or in combination with either dexamethasone or bortezomib and dexamethasone has shown considerable anti-tumor activity in t(11;14) MM with relapsed disease. Based on preclinical studies suggesting synergy when combined with bortezomib and phase 1 data showing efficacy for venetoclax, this combination was compared with bortezomib and dexamethasone (BortDex) in relapsed MM. While the BELLINI (NCT02755597) trial did demonstrate improved PFS with the combination, there were limited number of patients with t(11;14) treated with BortDex. The objective of this study was to assess real-world effectiveness of BortDex in patients with t(11;14) positive relapsed/refractory MM. Patients and methods: This non-interventional, retrospective observational cohort study included patients with t(11;14) MM from the International Myeloma Working Group (IMWG) retrospective study of t(11;14) MM. From the overall cohort, patients with t(11;14) MM receiving BortDex in ≥2 nd and ≤4 th line were initially selected. The cohort was further limited to patients with no evidence of allogeneic SCT within 16 weeks or autologous SCT within 12 weeks prior to BortDex initiation. Finally, patients non-refractory to prior PI regimen and not receiving BortDex regimen as part of a clinical trial were included in the study. Patient demographic and clinical characteristics along with real-world effectiveness outcomes including best response, overall survival (OS), and time to next therapy (TTNT) as a surrogate measure for progression-free survival (PFS) were assessed. All analyses were descriptive in nature and were conducted using the SAS 9.4 (SAS Institute Inc., Cary, NC, USA). Results: Overall, 144 patients who met the inclusion criteria were analyzed. Median age was 62.5 years, 62% were male. Patients had a median of 1 prior line (range 1-3) at start of BortDex, at a median of 18.4 months (range, 1-100) from diagnosis; 29% had a prior transplant. A PR or better was observed in 53% of patients with BortDex. The median TTNT for this cohort was 8.4 months and median OS was 46.1 months. Conclusions: This retrospective study of non-trial patients with t(11;14) MM provides a benchmark for newer therapies in this patient population for comparison with both venetoclax dexamethasone as well as combinations using the -BortDex backbone. Disclosures Emechebe: AbbVie: Current Employment, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company; Pharmaceutical/Biotech Companies: Current holder of stock options in a privately-held company. Kumar: Tenebio: Research Funding; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Oncopeptides: Consultancy; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Carsgen: Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche-Genentech: Consultancy, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Research Funding; Beigene: Consultancy; Antengene: Consultancy, Honoraria; Bluebird Bio: Consultancy; Merck: Research Funding; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; BMS: Consultancy, Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Research Funding. Goldschmidt: Takeda: Consultancy, Research Funding; Novartis: Honoraria, Research Funding; Mundipharma: Research Funding; MSD: Research Funding; Molecular Partners: Research Funding; Dietmar-Hopp-Foundation: Other: Grant; Sanofi: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Janssen: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Incyte: Research Funding; GSK: Honoraria; Chugai: Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; BMS: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Celgene: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Adaptive Biotechnology: Consultancy; Amgen: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Johns Hopkins University: Other: Grant. Mateos: Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Regeneron: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria; Sea-Gen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies: Honoraria, Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene - Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bluebird bio: Honoraria; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria; Oncopeptides: Honoraria. Kim: Janssen, BMS: Research Funding. Dimopoulos: Janssen: Honoraria; Takeda: Honoraria; Beigene: Honoraria; BMS: Honoraria; Amgen: Honoraria. Ludwig: Janssen, Celgene-BMS, Sanofi, Seattle Genetics: Consultancy, Speakers Bureau; Amgen, Takeda: Consultancy, Research Funding, Speakers Bureau. Handa: Kyowa Kirin: Research Funding; Chugai: Research Funding; Celgene: Honoraria, Research Funding; Daiichi Sankyo: Research Funding; Janssen: Honoraria; BMS: Honoraria; Ono: Honoraria; Sanofi: Honoraria, Research Funding; Abbvie: Honoraria; MSD: Research Funding; Shionogi: Research Funding; Takeda: Honoraria, Research Funding. Fernandez de Larrea: Janssen: Consultancy, Honoraria, Research Funding; BMS: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Takeda: Honoraria, Research Funding; GSK: Honoraria; Sanofi: Consultancy. Reece: Amgen: Consultancy, Honoraria; GSK: Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Sanofi: Honoraria; Millennium: Research Funding; Karyopharm: Consultancy, Research Funding; BMS: Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding. Raje: Celgene, Amgen, Bluebird Bio, Janssen, Caribou, and BMS: Other. Karve: AbbVie: Current Employment, Current equity holder in publicly-traded company. Arriola: AbbVie: Current Employment, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company. Ross: AbbVie: Current Employment, Current equity holder in publicly-traded company, Current holder of individual stocks in a privately-held company. Durie: Amgen: Other: fees from non-CME/CE services ; Amgen, Celgene/Bristol-Myers Squibb, Janssen, and Takeda: Consultancy.

Purpose The aim of the International Myeloma Working Group was to develop practical recommendations for the diagnosis and management of multiple myeloma–related renal impairment (RI). Methods Recommendations were based on published data through December 2015, and were developed using the system developed by the Grading of Recommendation, Assessment, Development, and Evaluation Working Group. Recommendations All patients with myeloma at diagnosis and at disease assessment should have serum creatinine, estimated glomerular filtration rate, and electrolytes measurements as well as free light chain, if available, and urine electrophoresis of a sample from a 24-hour urine collection (grade A). The Chronic Kidney Disease Epidemiology Collaboration, preferably, or the Modification of Diet in Renal Disease formula should be used for the evaluation of estimated glomerular filtration rate in patients with stabilized serum creatinine (grade A). International Myeloma Working Group criteria for renal reversibility should be used (grade B). For the management of RI in patients with multiple myeloma, high fluid intake is indicated along with antimyeloma therapy (grade B). The use of high-cutoff hemodialysis membranes in combination with antimyeloma therapy can be considered (grade B). Bortezomib-based regimens remain the cornerstone of the management of myeloma-related RI (grade A). High-dose dexamethasone should be administered at least for the first month of therapy (grade B). Thalidomide is effective in patients with myeloma with RI, and no dose modifications are needed (grade B). Lenalidomide is effective and safe, mainly in patients with mild to moderate RI (grade B); for patients with severe RI or on dialysis, lenalidomide should be given with close monitoring for hematologic toxicity (grade B) with dose reduction as needed. High-dose therapy with autologous stem cell transplantation (with melphalan 100 mg/m 2 to 140 mg/m 2 ) is feasible in patients with RI (grade C). Carfilzomib can be safely administered to patients with creatinine clearance > 15 mL/min, whereas ixazomib in combination with lenalidomide and dexamethasone can be safely administered to patients with creatinine clearance > 30 mL/min (grade A).