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Dispenzieri, Angela

0000-0001-8780-9512

Mayo Clinic

Mayo Clinic.

Citations 260

The enigma of rapid response vs safety in AL amyloidosis
Dispenzieri, Angela

Blood | October 15, 2026 | Volume: 148 | Issue: 16 | Pages: 1948-1950

10.1182/blood.2026035095 Get It

Chromosome 1q Gain Defines a Plasma Cell–Dominant Adverse‐Risk Subtype in AL Amyloidosis With Inferior Long‐Term Survival
Hellou, Tamer , Gauto‐Mariotti, Estefania , Alnughmush, Ahmed , Baughn, Linda B. , Kapoor, Prashant , Zanwar, Saurabh , Suzuki, Shinichiro , Steinhardt, Maximilian , Packard, Daniel George , Kourelis, Taxiarchis , Hayman, Suzanne R. , Hwa, Yi L. , Fonder, A., Hobbs, Miriam, Warsame, Rahma, Abdallah, Nadine , Kyle, Robert A., Kumar, Shaji , Mariotti, Estefania Gauto , Steinhardt, Maximilian , Packard, Daniel G , Kourelis, Taxiarchis V, Buadi, Francis K , Dingli, David , Leung, Nelson , Hwa, Yi L , Cook, Joselle M , Binder, Moritz , Abdallah, Nadine H , Lin, Yi , Go, Ronald S , Rajkumar, S Vincent , Gonsalves, Wilson , Kumar, Shaji K , Gertz, Morie A , Dispenzieri, Angela , Muchtar, E , Baughn, Linda B , Hellou, Tamer , Buadi, Francis K. , Dingli, David , Leung, Nelson , Fonder, Amie , Hobbs, Miriam, Warsame, Rahma , Cook, Joselle , Binder, Moritz , Lin, Yi , Go, Ronald S. , Kyle, R., Rajkumar, S. Vincent , Gonsalves, Wilson I. , Gertz, Morie A. , Dispenzieri, Angela , Muchtar, Eli

American Journal of Hematology | August 25, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1002/ajh.70484 Get It

ABSTRACT The prognostic relevance of multiple myeloma (MM)‐defined high‐risk (HR) cytogenetic abnormalities in AL amyloidosis is incompletely defined. We retrospectively evaluated 517 newly diagnosed AL amyloidosis patients seen at Mayo Clinic between 2012 and 2021 who had baseline plasma cell FISH. HR cytogenetics were defined as t (4;14), t (14;16), t (14;20), del(17p), or 1q gain/amplification (+1q). HR abnormalities were identified in 151 patients (29%); +1q accounted for most HR cases (122/151, 81%). Compared with standard‐risk (SR), patients harboring +1q demonstrated a greater clonal disease burden, including higher dFLC and bone marrow plasma cells, greater intact immunoglobulin secretion, higher plasma cell proliferative index, and enrichment for modified SLiM‐CRAB features. Hematologic and organ response patterns of +1q patients were generally comparable to SR patients, whereas non‐1q HR patients had a higher proportion of early hematologic responses. Patients harboring +1q demonstrated significantly inferior overall survival (OS) compared with both non‐1q HR patients and SR patients (median OS 57 months vs. not reached vs. 120 months, p = 0.02). In multivariable piecewise Cox analysis, the adverse prognostic impact of +1q was most evident beyond 24 months from diagnosis (HR 2.89, 95% CI 1.64–5.09, p < 0.001), whereas non‐1q HR lesions were not independently prognostic. These findings suggest that +1q identifies a biologically distinct AL amyloidosis subset characterized by plasma cell–dominant features and inferior long‐term disease control. In contrast, other MM‐defined HR cytogenetic abnormalities appear to have limited prognostic relevance in AL amyloidosis.
Utility of Prognostic Staging Systems in Transthyretin Amyloidosis Cardiomyopathy in the Era of Available Disease‐Modifying Treatment
Skov, Jens Kæstel , Clemmensen, Tor Skibsted , Scott, Christopher G. , AbouEzzeddine, Omar F. , CHANG, IAN C., Poulsen, Steen H., Grogan, Martha , Skov, Jens K , Clemmensen, Tor S , AbouEzzeddine, Omar F , Dispenzieri, Angela , Grogan, Martha , Scott, Christopher , Dispenzieri, Angela , Poulsen, Steen Hvitfeldt

Journal of the American Heart Association | August 8, 2026 | Volume: 15 | Issue: 16 | Pages: No page available

10.1161/jaha.125.048585 Get It

Background Prognostic staging systems in transthyretin amyloid (ATTR) cardiomyopathy were developed before the introduction of disease‐modifying treatment. We therefore evaluated contemporary risk stratification according to different staging systems in patients with ATTR cardiomyopathy. Methods All patients with newly diagnosed ATTR cardiomyopathy and baseline biomarker measurements from 2019 to 2023 were included from Mayo Clinic, Rochester, MN. Prognostic outcomes were calculated with Kaplan–Meier analysis for 3e staging systems in the main analysis: the National Amyloidosis Centre (NAC) staging system; a modified Mayo staging system using hsTNT (high‐sensitivity troponin T) cutoff >65 ng/L; the extended NAC model with a fourth stage (NT‐proBNP [N‐terminal pro‐B‐type natriuretic peptide] >10 000 ng/L). Results The study population consisted of 441 patients with a median age of 76 years, 93% were men, 85% were initiated on tafamidis, and 94% had wild‐type ATTR. Median follow‐up was 3.4 years, and 109 deaths occurred during follow‐up. The 3‐year survival for the Mayo stages were 92.3% (88.7–95.9) for stage I, 71.6% (63.0–81.3) for stage II, and 43.5% (32.4–58.5) for stage III. For the NAC system, 3‐year survival were 92.0% (89.0–95.7), 67.5% (59.0–77.3), and 47.0% (34.7–63.5) for stages I, II, and III, respectively. The 3‐year survival by the extended NAC system was 92.0 (69.0–79.2), 69.0% (60.1–79.2), 53.2% (39.9–70.8) and 34.4% (17.4–68.0) for stages I, II, III, and IV, respectively. Conclusions In a contemporary cohort of patients with ATTR cardiomyopathy, the NAC and modified Mayo staging systems remained equally effective in delineating clinically meaningful prognostic groups, whereas the extended NAC system identified a stage IV subgroup with high mortality.
Self-reported geriatric impairments and treatment toxicity in older patients with multiple myeloma
Abdallah, Nadine , Marar, Rosalyn, Yee, Claire , Bodily, Anna, Truman, Mia, Wildes, Tanya, Weivoda, Megan , Aug, Sarah, Smith, Byron, Kapoor, Prashant , Hayman, Suzanne R. , Dingli, David, Gonsalves, Wilson I, Zanwar, Saurabh , Kourelis, Taxiarchis , Warsame, Rahma , Lin, Yi, Rajkumar, S Vincent, Kumar, Shaji , Yee, Claire , Menser, Terri , Weivoda, Megan , Buadi, Francis K , Dispenzieri, Angela , Cook, Joselle M , Zanwar, Saurabh S , Binder, Moritz , Kourelis, Taxiarchis , Gertz, Morie A , Warsame, Rahma , Dueck, A. C. , Kumar, Shaji K , Wildes, Tanya M. , Buadi, Francis K. , Dispenzieri, Angela , Dingli, David , Gonsalves, Wilson I. , Cook, Joselle , Binder, Moritz , Gertz, Morie A. , Rajkumar, S. Vincent , Dueck, Amylou C.

Blood Advances | July 28, 2026 | Volume: 10 | Issue: 20 | Pages: 6957-6967

10.1182/bloodadvances.2026020579 Get It

Abstract Frailty influences treatment outcomes in older patients with multiple myeloma (MM), yet existing frailty tools capture limited geriatric domains and are incompletely studied in the context of contemporary therapies. We prospectively evaluated patient-reported comprehensive geriatric assessment (CGA) domains and their associations with treatment toxicity and patient-reported outcomes (PRO) in older adults with MM. Patients aged ≥60 years with newly diagnosed or relapsed/refractory MM initiating a new therapy completed electronic CGA and PRO questionnaires at baseline and 4 months. Outcomes included clinician- and patient-reported treatment toxicity, treatment adaptations, health care use, and health-related quality of life (HRQOL). A cumulative deficit frailty index (FI) was derived from CGA and HRQOL domains. Among 90 patients (mean age, 72 years), geriatric impairments were common, particularly physical function domains. High-grade nonhematologic toxicities were significantly associated with older age, comorbidities, patient-reported functional limitations, and anxiety. Toxicity rates on the PRO version of the Common Terminology Criteria for Adverse Events (CTCAE) were higher than on CTCAE, highlighting a discordance between physician- and patient-reported treatment toxicity. Frailty was present in 22% and associated with worse baseline HRQOL and increased high-grade nonhematologic toxicity but not treatment adaptations or health care use. Average CGA and HRQOL scores remained stable over 4 months, although individual trajectories varied. Patient-reported geriatric impairments are prevalent in older adults with MM and strongly associated with nonhematologic toxicities even in the contemporary treatment era. Physician-reported CTCAE may not fully reflect patients' symptom burden. Heterogeneity in individual geriatric trajectories during treatment emphasize the need for longitudinal assessment. This study was registered at www.clinicaltrials.gov as NCT05918185.
Predictors of posttransplant measurable residual disease negativity and impact on clinical outcomes in multiple myeloma
Bolarinwa, Abiola , Zanwar, Saurabh , Abdallah, Nadine , Nagaraj, Madhu , Seth, Sukriti, Buadi, Francis K. , Hayman, Suzanne R. , Gertz, Morie A. , Muchtar, Eli , Kapoor, Prashant , Gonsalves, Wilson I, Kourelis, Taxiarchis , Dingli, David, Warsame, Rahma , Lin, Yi, Hwa, Y., Rogers, Michelle Genevieve, Hobbs, Miriam A, Fonder, Amie , Jevremovic, Dragan, Rajkumar, S Vincent, Kumar, Shaji , Zanwar, Saurabh S , Dispenzieri, Angela , Muchtar, E , Kourelis, Taxiarchis , Warsame, Rahma , Leung, Nelson , Cook, Joselle M , Binder, Moritz , Hwa, Yi Lisa, Fonder, Amie , Kumar, Shaji K , Gertz, Morie A , Buadi, Francis K , Bolarinwa, Abiola B , Dispenzieri, Angela , Gonsalves, Wilson I. , Dingli, David , Leung, Nelson , Cook, Joselle , Binder, Moritz , Hobbs, Miriam, Jevremović, Dragan , Rajkumar, S. Vincent

Blood Advances | July 28, 2026 | Volume: 10 | Issue: 19 | Pages: 6694-6702

10.1182/bloodadvances.2026020294 Get It

Abstract Measurable residual disease (MRD) is a powerful prognostic tool in multiple myeloma, but predictors of achieving MRD negativity after autologous stem cell transplantation (ASCT) are not well defined. We studied 814 patients who achieved at least a very good partial response after ASCT between January 2016 and January 2023 and underwent MRD assessment by next-generation flow cytometry. Overall, 387 (48%) achieved MRD negativity after ASCT. The presence of t(11;14) (odds ratio [OR], 2.1; 95% confidence interval [CI], 1.4–3.2; P&lt; .01) and pretransplant response less than complete remission (OR, 2.1; 95% CI, 1.2-3.7; P&lt; .01) independently predicted MRD positivity. Patients who were MRD positive had inferior progression-free survival (PFS; hazard ratio [HR], 1.99; 95% CI, 1.53-2.58; P&lt; .001) and overall survival (HR, 1.62; 95% CI, 1.10-2.28; P = .009). Despite lower MRD-negative rate, 5-year PFS was similar among t(11;14) MRD positive (58%) and patients who were MRD negative (63%; P = .12). In patients who were MRD negative, the 5-year PFS was 73% in those without ≥2 HRCA compared with 55% in those with ≥2 HRCA (HR 1.9, 95% CI 1.2–3.3; P = .01). In the MRD-positive cohort, 5-year PFS was 53% in patients without ≥2 HRCA vs 17% in those with ≥2 HRCA (HR, 2.4; 95% CI, 1.6-3.6; P&lt; .01). In addition, higher residual clonal plasma cell burden within MRD-positive disease was associated with inferior PFS (HR, 2.4; 95% CI, 1.2-6.9; P = .002). This study highlights that the presence of t(11;14) independently predicts MRD positivity after ASCT, although it does not significantly affect prognosis in this subgroup.
Pathology-Based Validation of Quantitative SPECT/CT in Patients With Suspected Transthyretin Amyloid Cardiomyopathy
Tersalvi, Gregorio , Bois, Melanie C. , Scott, Christopher G. , Carey, Patricia , Garmany, Armin , Davies, Daniel R. , HOFFMAN, Andrew C., Zhang, Jun , Hruska, Carrie B. , Jouni, Hayan, Rodriguez-Porcel, Martin G., Askew, J. Wells , Bois, John P. , Young, Kathleen A. , Anavekar, Nandan S., CHANG, IAN C., Grogan, Martha , Maleszewski, Joseph J. , Homb, Andrew, Redfield, Margaret M. , Dispenzieri, Angela , Maleszewski, Joseph J , Homb, Andrew C, Redfield, Margaret M , Chareonthaitawee, Panithaya , Johnson, Geoffrey B , AbouEzzeddine, Omar F , Hruska, Carrie B , Scott, Christopher , Tersalvi, Gregorio , Carey, Patricia , Rodriguez‐Porcel, Martin , Anavekar, Nandan S., Dispenzieri, Angela , Chareonthaitawee, Panithaya , Johnson, Geoffrey B. , AbouEzzeddine, Omar F.

Circulation: Cardiovascular Imaging | July 23, 2026 | Volume: 19 | Issue: 8 | Pages: No page available

10.1161/circimaging.126.019832 Get It

BACKGROUND: Technetium-based cardiac amyloid radionuclide imaging enables noninvasive diagnosis of transthyretin amyloid cardiomyopathy (ATTR-CM), but conventional planar and visual semiquantitative approaches have important limitations. We developed the quantitative 3-dimensional Mayo 3D Score, defined as the ratio of mean left ventricular myocardial radiotracer uptake to right atrial blood-pool uptake using computed tomography (CT)-fused single-photon emission CT (SPECT) volumes of interest, and sought to validate its diagnostic performance against myocardial pathology. METHODS: Consecutive patients who underwent 99m Tc-pyrophosphate SPECT/CT at Mayo Clinic for suspected ATTR-CM between June 2017 and January 2025 with archived myocardial tissue were included. Baseline characteristics, including demographics, echocardiogram, biomarkers, visual semiquantitative, and Mayo 3D Score metrics, were collected. Myocardial specimens underwent histopathologic confirmation of amyloid, with amyloid subtype determination and further semiquantitative grading of amyloid burden and deposition patterns. RESULTS: Among 230 patients (median age, 72 years; 78% male), 107 (47%) had ATTR-CM, of whom 9 had hereditary ATTR-CM. The Mayo 3D Score showed excellent discrimination against pathology (area under the receiver operating characteristic curve, 0.92 [0.88–0.96]), exceeding planar Perugini (0.87 [0.83–0.92]; P =0.006), and heart-to-contralateral lung ratio (0.86 [0.81–0.91]; P =0.004) and comparable to SPECT Perugini (0.90 [0.86–0.94]; P =0.12). A cutoff ≥1.0 yielded 86.0% sensitivity, 92.7% specificity, 91.1% positive predictive value, and 88.4% negative predictive value. Among ATTR-positive cases, the Mayo 3D Score correlated strongly with semiquantitative amyloid burden (Spearman ρ=0.69), was higher in pericellular than nodular deposition patterns ( P <0.001), and was not associated with vascular involvement ( P =0.42). CONCLUSIONS: In patients with suspected ATTR-CM undergoing 99m Tc-pyrophosphate SPECT/CT, the Mayo 3D Score demonstrated superior diagnostic performance compared with planar metrics and comparable to SPECT Perugini, while correlating with myocardial ATTR burden and deposition patterns on pathology. These findings support its integration as a quantitative adjunct within clinical diagnostic ATTR-CM workflows.
POEMS Syndrome: 2026 Update on Diagnosis, Risk‐Stratification, and Management
Dispenzieri, Angela, Dispenzieri, Angela , Dispenzieri, Angela

American Journal of Hematology | July 7, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1002/ajh.70438 Get It

ABSTRACT Disease Overview POEMS syndrome is a life‐threatening syndrome due to an underlying plasma cell neoplasm. The major criteria for the syndrome are polyneuropathy, clonal plasma cell disorder (PCD), sclerotic bone lesions, elevated vascular endothelial growth factor, and the presence of Castleman disease. Minor features include organomegaly, endocrinopathy, characteristic skin changes, papilledema, extravascular volume overload, and thrombocytosis. Diagnosis The diagnosis of POEMS syndrome is made with three of the major criteria, two of which must include polyneuropathy and clonal plasma cell disorder, and at least one of the minor criteria. Risk Stratification Because the pathogenesis of the syndrome is not well understood, risk stratification is limited to clinical phenotype rather than specific molecular markers. Risk factors include low serum albumin, age, pleural effusion, pulmonary hypertension, and reduced eGFR. Risk‐Adapted Therapy For those patients with a dominant plasmacytoma, first line therapy is irradiation. Patients with diffuse sclerotic lesions or disseminated bone marrow involvement should receive systemic therapy. Corticosteroids are temporizing, but alkylators and lenalidomide are the mainstays of treatment, the former either in the form of low dose conventional therapy or as high‐dose conditioning for stem cell transplantation. Thalidomide and bortezomib also have activity, but their benefit needs to be weighed against their risk of exacerbating the peripheral neuropathy. Daratumumab combinations also appear promising based on case series. Prompt recognition and institution of both supportive care measures and therapy directed against the plasma cell result in the best outcomes.
Clinical course, risk factors, and therapeutic response in multiple myeloma with central nervous system involvement
Xiao, Alexander , Zanwar, Saurabh , Lin, Yi, Kapoor, Prashant , Abdallah, Nadine , Baudi, Francis, Dingli, David, Gertz, Morie A. , Gonsalves, Wilson I, Hayman, Suzanne R. , Kourelis, Taxiarchis , Tan, Melinda SY, Warsame, Rahma , Rajkumar, S Vincent, Kumar, Shaji , Dingli, David , Buadi, Francis K. , Lin, Yi , Lin, Yi , Buadi, Francis K , Binder, Moritz , Dispenzieri, Angela , Dingli, David , Gertz, Morie A , Gonsalves, Wilson , Kourelis, Taxiarchis , Leung, Nelson , Muchtar, E , Siddiqui, Mustaqeem A , Tan, Melinda , Warsame, Rahma , Rajkumar, S Vincent , Kumar, Shaji K , Xiao, Alexander H , Binder, Moritz , Dispenzieri, Angela , Gonsalves, Wilson I. , Leung, Nelson , Muchtar, Eli , Siddiqui, Mustaqeem , Rajkumar, S. Vincent

Blood Advances | June 25, 2026 | Volume: 10 | Issue: 17 | Pages: 5828-5833

10.1182/bloodadvances.2026020668 Get It

Abstract Extramedullary disease (EMD) is increasingly recognized in relapsed/refractory multiple myeloma (MM), with central nervous system involvement (CNS-MM) representing a rare but highly aggressive manifestation associated with dismal outcomes. Data on its incidence and optimal management, particularly in the era of cellular and bispecific therapies, remain limited. We conducted a retrospective analysis of patients with MM with pathology-confirmed EMD treated at our institution between January 2000 and December 2023. CNS-MM was defined by parenchymal or leptomeningeal involvement. Clinical features, cytogenetics, treatments, and outcomes were analyzed, with predictors of CNS involvement evaluated among patients with EMD. Among 304 patients with EMD, 20 (6.5%) had CNS-MM. CNS involvement occurred a median of 19.2 months after MM diagnosis, though 15% presented at diagnosis. CNS-MM was strongly associated with high-risk cytogenetics (odds ratio [OR], 3.7) and additional visceral EMD (OR, 4.6). Median overall survival (OS) from CNS-MM diagnosis was 4.2 months. Outcomes were significantly improved in patients receiving chimeric antigen receptor T-cell therapy or bispecific antibodies, with a median OS of 19.2 months vs 1.2 months in those who did not receive immune effector therapies. Intrathecal (IT) chemotherapy demonstrated limited and transient benefit. In conclusion, CNS-MM is an aggressive complication enriched in high-risk, multifocal EMD with extremely poor prognosis. Cellular and bispecific therapies show promising activity and may meaningfully improve survival, whereas IT therapy appears to have limited efficacy. Prospective studies are needed to define optimal treatment strategies for CNS-MM.
Efficacy and Safety of Anselamimab in Immunoglobulin Light Chain Amyloidosis: Results From the Randomized CARES Trials
Wechalekar, Ashutosh , Sanchorawala, Vaishali , Zepeda, Victor H. Jimenez-, Suzuki, Kenshi, Lentzsch, Suzanne , Huart, Antoine , Carpinteiro, Alexander , Swenson, Eugene , Khan, Zilehuma, Catini, Julia, Kulkarni, Hrishikesh, Meltzer, Brian, Lake, Stephen, Liedtke, Michaela , Investigators, for the CARES, Ting, Stephen Bek Ngie, Mollee, Peter Norman, Meuleman, Nathalie, Delforge, Michel, Zepeda, Victor Jimenez, Zhang, Shuyang, Du, Xin, Wang, Jianan, Qian, Honglan, Sun, Chunyan, Belhadj, Karim , Arnulf, Bertrand, Karlin, Lionel, Macro, Margaret, Colella, Jean-Marc Schiano De, Stoppa, Anne-Marie, Viallard, Jean-Francois, Fenk, Roland, Hansen, Timon, Girke, Vera, Nogai, Axel, Gatt, Moshe, Lavi, Noa, Magen, Hila , Palladini, Giovanni, Pane, Fabrizio, Buda, Gabriele , Ishida, Tadao, Iida, Shinsuke, Jamroziak, Krzysztof, Byun, Jamin, Koh, Youngil, Kim, Kihyun, Villamediana, Ramón Lecumberri, Lopez, Maria Teresa Cibeira, Martínez, Irene Romera, Duarte, Rafael , Castello, Isabel Angela Krsnik, Garcia, Maria Esther Gonzalez , Chacon, Eusebio Narciso Martin, Martínez, Javier Alberto Rojas , Valent, Jason , Rosenzweig, Michael A., Chung, Alfred, Wong, Sandy, Bumma, Naresh , Comenzo, Raymond, Gaballa, Mahmoud, Lee, Hans C., Kaufman, Gregory P., Passero, Frank, Stockerl-Goldstein, Keith, Waxman, Adam, D'Souza, Anita, Cowan, Andrew, Lee, Sarah, Libby, Edward, Godara, Amandeep , Kovacsovics, Tibor, Sengsayadeth, Salyka, Goodman, Stacey , Chaulagain, Chakra, Wechalekar, Ashutosh D. , Dispenzieri, Angela , Sanchorawala, Vaishali , Kastritis, Efstathios , Lentzsch, Suzanne , Meltzer, Brian , Liedtke, Michaela , Dispenzieri, Angela , Kastritis, Efstathios , Bhutani, Divaya , Bianchi, Giada , Suzuki, Kenshi , Khan, Zilehuma, Kulkarni, Hrishikesh, Lake, Stephen, Ting, Stephen B. , Mollee, Peter , Agis, Hermine , Straßl, Irene , Meuleman, Nathalie , Delforge, Michel , Sedlák, František , Jaccard, Arnaud , Arnulf, Bertrand , Karlin, Lionel , Macro, Margaret , Stoppa, Anne‐Marie, Bridoux, Frank , Chalopin, Thomas , Viallard, Jean‐François , Fenk, Roland , Symeonidis, Argiris , Annibali, Ombretta , Iida, Shinsuke, Ikezoe, Takayuki , Jamroziak, Krzysztof , Koh, Youngil, López, Maria Teresa Cibeira, Rios, Rafael, Garcia, Maria Esther Gonzalez, Chacón, Eusebio Martín, Valent, Jason Neil , Rosenzweig, Michael, Comenzo, Raymond L. , Gaballa, Mahmoud , Kaufman, Gregory P., Medvedova, Eva , Passero, Frank Charles , Stockerl-Goldstein, Keith , Chaulagain, Chakra P.

Journal of Clinical Oncology | May 29, 2026 | Volume: 44 | Issue: 20 | Pages: 1899-1910

10.1200/jco-26-00755 Get It

PURPOSE In immunoglobulin light chain (AL) amyloidosis, amyloid fibrils cause organ dysfunction. Anselamimab, a monoclonal antibody, selectively binds to amyloid fibrils, accelerating their clearance. METHODS Newly diagnosed patients with European modification of Mayo 2004 stage IIIa or IIIb AL amyloidosis were randomly assigned to receive anselamimab or placebo with cyclophosphamide, bortezomib, and dexamethasone (with or without daratumumab). The primary end point was a hierarchical composite of time to all-cause mortality (ACM) and frequency of cardiovascular hospitalizations (CVHs), analyzed using the Finkelstein-Schoenfeld test and win ratio estimation. RESULTS Among 406 randomly assigned patients, the primary end point win ratio for anselamimab versus placebo was 1.11 (95% CI, 0.83, 1.50; P = .332) and the hazard ratio (HR) for ACM was 0.80 (95% CI, 0.57, 1.13; P = .290). CVH rates in the anselamimab and placebo groups were 0.59 (95% CI, 0.42, 0.83) and 0.89 (95% CI, 0.55, 1.43), respectively ( P = .145). Among patients with kappa isotype (n = 72), the win ratio was 2.06 (95% CI, 0.98, 4.31; P = .100) and anselamimab reduced ACM by 62% versus placebo (HR, 0.38; 95% CI, 0.17 to 0.86; nominal P = .012), and CVH by 71% (IRR, 0.29; 95% CI, 0.10 to 0.87; nominal P = .028) with improvements in Kansas City Cardiomyopathy Questionnaire-Overall Score. There was no clinical benefit observed in the lambda population. Anselamimab was generally well-tolerated; safety data were comparable between treatment arms overall. CONCLUSION Treatment with anselamimab, an antifibril antibody used alongside antiplasma cell dyscrasia therapy, while not meeting the primary end point in the overall population, significantly improved ACM and CVH in patients with kappa AL, potentially offering a new therapeutic option for this isotype.