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Gagelmann, Nico

https://orcid.org/0000-0002-0891-1744

Mayo Clinic

University Medical Center Hamburg-Eppendorf

Citations 5

Molecular-Based Ecosystem to Improve Personalized Medicine in Chronic Myelomonocytic Leukemia
Lanino, Luca , Hunter, Anthony M. , Gagelmann, Nico, Robin, M., Dall'Olio, Daniele , Flamigni, Alice, Gurnari, Carmelo, Wang, Yu‐Hung , Pleyer, Lisa , Xicoy, B., Montalban-Bravo, Guillermo, Shih, Lee-Yung, Alsugair, Ali, Gregorio, Caterina, Platzbecker, Anne Sophie, Sallman, David A., Fariselli, Piero, Garcia-Manero, Guillermo, Platzbecker, U, Solé, Francesc Gessé, Díez-Campelo, María, Maciejewski, Jaroslaw, Bejar, Rafael, Thol, Felicitas, Kroger, N., Fenaux, Pierre, Sanz, G. F., Kordasti, S., Santini, Valeria, Zeidan, Amer M., Komrokji, Rami S., Haferlach, Torsten, Germing, Ulrich, Castellani, Gastone, D'Amico, Saverio, Patnaik, M., Ieva, F., Tefferi, Ayalew, Padron, Eric , Porta, Matteo Giovanni Della, Alliance, for the iCPSS, Haque, Tamanna, Abdel-Wahab, Omar, Geissler, Klaus, Bataller, Alex, Bazinet, Alexandre , Meggendorfer, Manja , Quintavalla, Mirco, Bruseghini, Alessandro , Carota, Luciana , Dall'Olio, Lorenzo, Travaglino, Erica , Zamora, Lurdes López, Quintela, David, Jerez, Andrés , Cornejo, Elena, Martín, Paloma García, Díaz-Beyá, Marina, Pita, Alejandro Avendano, Roldán, Verónica , Suarez, Dolly Viviana Fiallo, Velasco, Estefania Cerezo, Calabuig, Marisa , Such, Esperanza, Castilla-Llorente, Cristina, Bulabois, Claude Eric, Souchet, Laëtitia, Bernardi, Massimo, Chiusolo, Patrizia, Borin, Lorenza, Follo, Matilde Yung, Consagra, Angela , Passamonti, Francesco, Diral, Elisa , Vucinic, Vladan, Bergonzi, Gregorio Maria , Hou, Hsin-An, Russo, Antonio, Tentori, Cristina Astrid , Buizza, Alessandro , Ferrari, Ivan, Matteo, Maria Di, Crespi, Alessandra, Figini, Giulia , Delponte, Camilla, Zampini, Matteo, Riva, Elena, Delleani, Mattia , Iascone, Eleonora, Ficara, Francesca , Ventura, Denise, Pinocchio, Nicole, Santoro, Armando, Kiwan, Ahmad , Ali, Najla H. Al, Zeidan, Amer M. , Robin, Marie , Dall’Olio, Daniele , Riva, Elena , Gagelmann, Nico , Robin, Marie , Sala, Claudia , Gurnari, Carmelo , Wang, Yu-Hung , Shih, Lee‐Yung , Alsugair, Ali , Fathima, Saubia , Gregorio, Caterina , Rollo, Cesare , Platzbecker, Anne Sophie , Asti, Gianluca , Itzykson, Raphael , Sallman, David A , Fariselli, Piero , Kern, Wolfgang , Garcia-Manero, Guillermo , Platzbecker, Uwe , Solé, Francesc , Diez-Campelo, Maria , Maciejewski, Jaroslaw P , Bejar, Rafael , Thol, Felicitas , Savona, Michael R , Sanz, Guillermo F , Kordasti, Shahram , Santini, Valeria , Zeidan, Amer M , Komrokji, Rami S , Castellani, Gastone , D'Amico, Saverio , Patnaik, Mrinal , Ieva, Francesca , Solary, Eric , Padron, Eric , Della Porta, Matteo Giovanni , Buizza, Alessandro , Ficara, Francesca , Lanino, Luca , Gagelmann, Nico , Gurnari, Carmelo , Xicoy, Blanca , Montalban‐Bravo, Guillermo , Fathima, Saubia , Gregorio, Caterina , Palomo, Laura , Itzykson, Raphaël , Sallman, David A. , Kern, Wolfgang , Garcia‐Manero, Guillermo , Platzbecker, Uwe , Solé, Françesc , Díez‐Campelo, María , Thol, Felicitas , Kröger, Nicolaus , Savona, Michael R. , Fenaux, Pierre , Sanz, Guillermo , Santini, Valeria , Fontenay, Michaëla , Komrokji, Rami S. , Haferlach, Torsten , Germing, Ulrich , Solary, Éric , Tefferi, Ayalew , Haque, Tamanna , Bataller, Alex , Sauta, Elisabetta , Sanavia, Tiziana , Dall'Olio, Lorenzo, Díaz‐Beyá, Marina , Roldan, Veronica, Fiallo, Dolly Viviana , Such, Esperanza , Castilla‐Llorente, Cristina , Bulabois, Claude‐Eric , Awada, Hussein , Chiusolo, Patrizia , Curti, Antonio , Giaccone, Luisa , Finelli, Carlo , Casetti, Ilaria Carola , Onida, Francesco , Passamonti, Francesco , Vučinić, Vladan , Voso, Maria Teresa , Hou, Hsin-An, Chou, Wen‐Chien , Yao, Chi‐Yuan , Lin, Chien‐Chin , Tien, Hwei‐Fang , Campagna, Alessia , Ubezio, Marta , Todisco, Gabriele , Maggioni, Giulia , Matteo, Maria Di, Pesce, Francesco , Zampini, Matteo , Crisafulli, Laura , Ventura, Denise , Pinocchio, Nicole , Brindisi, Matteo , VanOudenhove, Jennifer , Ali, Najla H. Al, Graubert, Timothy Aaron , Thota, Swapna , Griffiths, Elizabeth A.

Journal of Clinical Oncology | March 27, 2026 | Volume: 44 | Issue: 17 | Pages: 1608-1623

10.1200/jco-25-02116 Get It

PURPOSE Chronic myelomonocytic leukemia (CMML) is a rare myeloid neoplasm characterized by clinical heterogeneity and is associated with poor outcomes. To date, limited molecular information has been incorporated into disease classification and risk stratification. We aimed to integrate genomic features into the clinical decision-making process for CMML. PATIENTS AND METHODS We analyzed a retrospective cohort of 3013 patients with CMML (training set) and a prospective population of 516 patients (validation set). Using an innovative framework for multimodal data analysis, we developed molecular-based disease taxonomy and prognostication. RESULTS Unsupervised clustering identified nine entities with distinct genomic features and outcomes ( P < .001), including splicing machinery, transcription factors, signal transduction and tyrosine kinase pathways aberrations, and high-risk molecular signatures. Notably, 15% of patients showed molecular/clinical overlap with other myeloid neoplasms. We integrated molecular and clinical information to build the international CMML Prognostic Scoring System (iCPSS), incorporating mutations in nine genes together with hematologic parameters and cytogenetic abnormalities. The iCPSS identified five groups with distinct probability of overall and leukemia-free survival in both training and validation cohorts ( P < .001), outperforming existing prognostic models. Importantly, 55% of patients were reassigned to higher or lower risk groups by the iCPSS. Decision analysis demonstrated that iCPSS could refine the optimal timing of allogeneic transplantation at the individual level; compared with conventional prognostic tools, iCPSS-based decision modeling changed transplantation strategy in 31% of cases, resulting in a significant gain-in-life expectancy for eligible patient population ( P < .001). A federated learning platform was implemented to enable continuous, privacy-preserving model update across multiple centers. CONCLUSION Molecular information improves CMML classification and prognostication, supports more effective clinical decision making, and potentially refines the design of clinical trials.
Sequential targeting in multiple myeloma: talquetamab, a GPRC5D bispecific antibody, as a bridge to BCMA CAR-T therapy
Dhakal, Binod , Akhtar, Othman Salim , Jensen, Alexandria , Banerjee, Rahul , Friend, Reed, Martinez, Mariola Alejandra Vazquez, Wagner, Charlotte B , Davis, James A. , Afrough, Aimaz , Bhutani, Manisha , Freeman, Ciara L. , Mikkilineni, Lekha , Raza, Shahzad , Anderson, Larry D. , Kapoor, Prashant , Hosoya, Hitomi , Gaballa, Mahmoud , Midha, Shonali , Alsina, Melissa , Sborov, Douglas W. , Patel, Krina K. , Lin, Yi , Ferreri, Christopher J. , Kumar, Anupama, Cowan, Andrew J., Sidana, Surbhi , Jensen, Alexandria , Banerjee, Rahul , Friend, Reed , Vazquez-Martinez, Mariola A , Wagner, Charlotte , Davis, James A , Castaneda Puglianini, Omar , Dima, Danai , Bhutani, Manisha , Parrondo, Ricardo D , Freeman, Ciara L , Anderson, Larry D , Hosoya, Hitomi , Chhabra, Saurabh , Grajales-Cruz, Ariel F , Sborov, Douglas W , Patel, Krina , Hansen, Doris K , Costa, Luciano J , Merz, Maximilian , Sidana, Surbhi , Raza, Shahzad , Dhakal, Binod , Fandrei, David , Pan, Darren , Richard, Shambavi , Rees, Matthew J. , Costello, Patrick , Vazquez‐Martinez, Mariola , Pasvolsky, Oren , Puglianini, Omar Castañeda , Reshef, Ran , Dima, Danai , Nadeem, Omar , Chhabra, Saurabh , Grajales‐Cruz, Ariel , Gagelmann, Nico , Hansen, Doris K. , Costa, Luciano J. , Merz, Maximilian

Blood | August 1, 2025 | Volume: 146 | Issue: 17 | Pages: 2063-2072

10.1182/blood.2025029773 Get It

Abstract Ciltacabtagene autoleucel (cilta-cel) and idecabtagene vicleucel (ide-cel), 2 B-cell maturation antigen (BCMA)–directed chimeric antigen receptor T-cell (CAR-T) therapies, have transformed outcomes for relapsed/refractory multiple myeloma; however, the 6 to 8 weeks manufacturing time risks disease progression or death in up to 10% of patients. Talquetamab, a G-protein–coupled receptor, family C, group 5, member D (GPRC5D)–targeting bispecific antibody, represents a promising option. We performed a multi-institutional retrospective analysis across 20 centers (18 United States, 2 Germany) evaluating talquetamab as a bridging therapy prior to cilta-cel or ide-cel. Among 134 patients receiving talquetamab, 119 proceeded to CAR-T (n = 98 cilta-cel, n = 21 ide-cel). Reasons for not proceeding (n = 15) included progression (n = 7), manufacturing failure (n = 6), or patient decision (n = 2). Median age was 65 years and had median 5 prior lines of therapy. Notably, 85% would not have met CARTITUDE-1/KarMMa eligibility criteria. Talquetamab was administered for a median 23 days. Toxicity was manageable: no grade ≥3 cytokine release syndrome (CRS), 2% grade 3 immune effector cell–associated neurotoxicity syndrome (ICANS) and grade 1 to 2 talquetamab unique toxicities (70% oral, 38% skin, and 17% nail; 60% resolved). Talquetamab achieved 71% response rate. After CAR-T, 88% responded (54% complete response), with low-grade toxicities (2 grade ≥3 CRS, 1 grade 3 ICANS, and 5% grade ≥3 infections). Two cases of facial palsy and 1 acute myeloid leukemia occurred. Talquetamab correlated with sustained soluble BCMA decline and peak CAR-T expansion around day 14. Talquetamab bridging appears safe, enabling the majority of difficult-to-treat patients to successfully proceed to BCMA CAR-T therapy.
Role of allo-HCT in “nonclassical” MPNs and MDS/MPNs: recommendations from the PH&G Committee and the CMWP of the EBMT
Hernández‐Boluda, Juan Carlos , Raj, Kavita , Kenyon, Michelle , Robin, Marie , Sockel, Katja , Sánchez‐Ortega, Isabel , Arcaini, Luca , Battipaglia, Giorgia , Ciceri, Fabio , Drozd‐Sokołowska, Joanna , Funke, Vaneuza Araújo Moreira , Gangat, Naseema , Harrison, Claire , Khoury, Joseph D. , Padron, Eric , Patnaik, Mrinal M. , Pemmaraju, Naveen , Radia, Deepti , Reiter, Andreas , Tefferi, Ayalew , Vannucchi, Alessandro M., Polverelli, Nicola , Hernández-Boluda, Juan Carlos , Gurnari, Carmelo , Raj, Kavita , Czerw, Tomasz , Kenyon, Michelle , Robin, Marie , Sánchez-Ortega, Isabel , Arber, Daniel A , Battipaglia, Giorgia , Chalandon, Yves , Cross, Nicholas C P , Drozd-Sokolowska, Joanna , Funke, Vaneuza , Gangat, Naseema , Hobbs, Gabriela S , Jain, Tania , Khoury, Joseph , Kiladjian, Jean-Jacques , Kröger, Nicolaus , Malcovati, Luca , Martino, Massimo , Mesa, Ruben , Palandri, Francesca , Patnaik, Mrinal , Pemmaraju, Naveen , Scheid, Christof , Wiseman, Daniel H , Yakoub-Agha, Ibrahim , Arcaini, Luca , Polverelli, Nicola , Onida, Francesco , Gurnari, Carmelo , Ruggeri, Annalisa , Arber, Daniel A. , Duarte, Fernando Barroso , Battipaglia, Giorgia , Chalandon, Yves , Cross, Nicholas C.P. , Gagelmann, Nico , Gotlib, Jason , Guglielmelli, Paola , Hobbs, Gabriela , Jain, Tania , Kiladjian, Jean‐Jacques , Kröger, Nicolaus , Malcovati, Luca , Martino, Massimo , Mesa, Ruben A. , Orazi, Attilio , Palandri, Francesca , Passamonti, Francesco , Russo, Domenico , Scheid, Christof , Wiseman, Daniel H. , Yakoub‐Agha, Ibrahim , McLornan, Donal P.

Blood | March 19, 2025 | Volume: 145 | Issue: 22 | Pages: 2561-2573

10.1182/blood.2024028000 Get It

Abstract “Nonclassical” myeloproliferative neoplasms (MPNs) and myelodysplastic/myeloproliferative neoplasms (MDS/MPNs) represent a heterogeneous group of malignancies characterized by a wide range of clinical manifestations. Unlike classical MPNs, there is no standardized management approach for these conditions, particularly concerning the indications for and management of allogeneic hematopoietic cell transplantation. To address this gap, the European Society for Blood and Marrow Transplantation (EBMT) Practice Harmonization and Guidelines (PH&G) Committee and the Chronic Malignancies Working Party (CMWP) have collaborated to develop shared guidelines aimed at optimizing the selection and management of patients with these rare forms of neoplasms. A comprehensive review of the literature from the publication of the revised fourth edition of the (2016) World Health Organization classification onward was conducted. A multidisciplinary group of experts in the field convened to produce this document, which was developed through multiple rounds of draft circulation. Key recommendations include the early identification of potential transplant candidates, particularly in cases of chronic neutrophilic leukemia, chronic eosinophilic leukemia (CEL)/CEL, not otherwise specified (CEL-NOS), myeloid/lymphoid neoplasm with eosinophilia and tyrosine kinase gene fusions with FGFR1, JAK2, ABL1, and FLT3 rearrangements, MDS/MPN with neutrophilia/atypical chronic myeloid leukemia, and MDS/MPN, NOS. For patients with MPN, NOS/MPN unclassifiable, standard recommendations for myelofibrosis should be applied. Similarly, in MDS/MPN with thrombocytosis, transplantation is recommended on the basis of established MDS guidelines. Given the current lack of robust evidence, this document will serve as a valuable resource to guide future research activities, providing a framework for addressing critical unanswered questions and advancing the field.
A Molecular-Based Ecosystem to Improve Personalized Medicine in Patients with Chronic Myelomonocytic Leukemia (CMML)
Dall'Olio, Lorenzo, Pleyer, Lisa , Montalban‐Bravo, Guillermo , Bazinet, Alexandre , Meggendorfer, Manja , Sauta, Elisabetta, Travaglino, Erica , Quintela, David, Jerez, Andrés , Cornejo, Elena, Martín, Paloma García, Roldán, Verónica , Suarez, Dolly Viviana Fiallo, Velasco, Estefania Cerezo, Calabuig, Marisa , Souchet, Laëtitia, Borin, Lorenza, Diral, Elisa , Vučinić, Vladan , Russo, Antonio , Tentori, Cristina Astrid , Buizza, Alessandro, Delleani, Mattia , Consagra, Angela , Kiwan, Ahmad , Ali, Najla H. Al, Sallman, David A. , Garcia-Manero, Guillermo, Follo, Matilde Y. , Maciejewski, Jaroslaw P. , Bejar, Rafael, Thol, Felicitas , Fenaux, Pierre , Haferlach, Torsten, Germing, Ulrich, Patnaik, Mrinal M. , Padron, Eric , Lanino, Luca , Hunter, Anthony M. , Gagelmann, Nico , Robin, Marie , Sala, Claudia , Dall’Olio, Daniele , Gurnari, Carmelo , Dall'Olio, Lorenzo, Wang, Yu‐Hung , Xicoy, Blanca , Shih, Lee‐Yung , Haque, Tamanna Zohra , Abdel‐Wahab, Omar , Geissler, Klaus H. , Bataller, Alex , Casetti, Ilaria Carola , Sauta, Elisabetta , Palomo, Laura , Zamora, Lurdes , Díaz‐Beyá, Marina , Pita, Alejandro Avendaño, Roldan, Veronica, Such, Esperanza , Sanz, Guillermo , Platzbecker, Anne Sophie , Castilla‐Llorente, Cristina , Bulabois, Claude‐Eric , Awada, Hussein , Bernardi, Massimo , Chiusolo, Patrizia , Curti, Antonio , Giaccone, Luisa , Onida, Francesco , Passamonti, Francesco , Bergonzi, Gregorio Maria , Voso, Maria Teresa , Hou, Hsin‐An , Chou, Wen‐Chien , Yao, Chi‐Yuan , Lin, Chien‐Chin , Tien, Hwei‐Fang , Campagna, Alessia , Ubezio, Marta , Todisco, Gabriele , Maggioni, Giulia , Asti, Gianluca , Zampini, Matteo , Riva, Elena , Ficara, Francesca , Santoro, Armando , Carota, Luciana , Sanavia, Tiziana , Rollo, Cesare , VanOudenhove, Jennifer , Fariselli, Piero , Kern, Wolfgang , Garcia‐Manero, Guillermo , Thota, Swapna , Griffiths, Elizabeth A. , Finelli, Carlo , Platzbecker, Uwe , Solé, Françesc , Díez‐Campelo, María , Bejar, Rafael , Kröger, Nicolaus , Itzykson, Raphaël , Graubert, Timothy Aaron , Fontenay, Michaëla , Zeidan, Amer M. , Komrokji, Rami S. , Santini, Valeria , Haferlach, Torsten , Germing, Ulrich , D'Amico, Saverio , Castellani, Gastone , Solary, Éric , Porta, Matteo Giovanni Della

Blood | December 5, 2024 | Volume: 144 | Issue: Supplement 1 | Pages: 1003-1003

10.1182/blood-2024-200104 Get It

Background. Study of myeloid neoplasms (MN) has been rapidly transformed by genome characterization. Gene mutations have been reported to influence disease phenotype and risk of disease progression, and the evaluation of mutational status can provide valuable insights to improve the decision-making process. In this international study, we evaluated the clinical impact of mutational screening in patients with CMML, which is characterized by significant clinical and genomic heterogeneity, including a substantial proportion of patients with poor outcomes and unmet needs. Currently, only limited molecular information has been incorporated into CMML classification and prognostication. Methods. We retrospectively collected 3182 CMML patients. We used MOSAIC, an AI-based framework for multimodal analysis in rare cancers (PMID: 38875514) to develop innovative, molecular-based tools for classification and prognostication. An independent validation of the results on 516 prospectively collected patients was performed. Results. Bayesian Networs and Hierarchical Dirichlet Processes were used to identify genomic associations and define a CMML molecular classification. We identified 11 clusters with distinct clinical and genomic features, including splicing machinery, signal transduction and tyrosine kinase pathways aberrations, and high-risk molecular signatures (i.e., AML-like and TP53 mutations). Up to 15% of patients showed clear genomic overlap with other MN. Importantly, extensive multi-color flow cytometry on T lymphocytes, NK and myeloid cells (BD FACSymphony A5 Cell Analyzer) revealed specific immunologic and inflammation signatures associated with molecular subgroups. We then integrated molecular and clinical information to build an international CMML Prognostic Scoring System (iCPSS). We assessed the performance of different statistical and AI-based methods; L1-penalized Cox Model resulted as the best performing method. Selected features included hematological parameters (WBC, Hb, PLT and marrow blasts), cytogenetic abnormalities, and mutations in 10 genes (ASXL1, DNMT3A, EZH2, NRAS, RUNX1, SETBP1, STAG2, TET2, TP53, U2AF1). By Bayesian thresholds optimization, we identified 5 risk classes (i.e., very-low, low, intermediate, high and very-high) with median overall survival (OS) ranging from 99 to 9 months (P&lt;.001), and median leukemia-free survival (LFS) ranging from 210 to 18 months (P&lt;.001). iCPSS provided better patient discrimination across all clinical endpoints compared to currently available prognostic tools, with a Concordance Index (CI) for OS of 0.75 versus 0.62-0.64, respectively. Notably, compared to available scoring systems, up to 40% of patients were reassigned to higher or lower risk classes by the iCPSS. External validation on an independent prospective cohort confirmed that the performance of iCPSS is superior to existing prognostic models (CI for OS 0.71 vs 0.54-0.61, respectively) To demonstrate the clinical utility of iCPSS, we focused on 753 patients who underwent allogeneic stem cell transplantation (HSCT). In multivariable analysis, iCPSS stratified the probability of OS post-HSCT (P&lt;.001) and identified groups of patients with different probabilities of disease relapse, ranging from 9% to 62% (P&lt;.001). We employed a clinical- and genomic-based decision support system (PMID: 38723212) to determine the optimal timing of HSCT. Preliminary analyses indicated that higher-risk patients according to iCPSS (i.e., intermediate, high, and very high) benefit from an immediate HSCT strategy. Lower-risk patients (i.e., very low and low) had life expectancy maximized with delayed HSCT. Modeling decision analysis using iCPSS compared to conventional scores, resulted in a change in transplantation policy for a significant proportion of patients (up to 25%). Conclusion. Molecular information significantly improves the classification of CMML patients, providing a basis for refining diagnostic boundaries with other MN and for a more rational inclusion of patients in clinical trials. The iCPSS demonstrated superior performance over currently available scoring systems and improved HSCT decision making process.
Role of allogeneic transplantation in chronic myelomonocytic leukemia: an international collaborative analysis
Robin, Marie , Wreede, Liesbeth C. de , Padron, Eric , Bakunina, Katerina , Fenaux, Pierre , Köster, Linda, Nazha, Aziz , Rampal, Raajit K. , Sockel, Katja , Gagelmann, Nico , Eikema, Dirk‐Jan, Potter, Victoria , Killick, Sally , Legrand, Faézeh, Broom, Angus, Garcia‐Manero, Guillermo , Rizzoli, Vittorio, Hayden, Patrick , Patnaik, Mrinal M. , Yakoub‐Agha, Ibrahim , Itzykson, Raphaël , de Wreede, Liesbeth C , Komrokji, Rami S , Gagelmann, Nico , Finke, Jürgen , Solary, Eric , Patnaik, Mrinal , Yakoub-Agha, Ibrahim , Itzykson, Raphael , Robin, Marie , Beelen, Dietrich Wilhelm , Komrokji, Rami S. , Radujkovic, Aleksandar , Solary, Éric , Onida, Francesco

Blood | June 6, 2022 | Volume: 140 | Issue: 12 | Pages: 1408-1418

10.1182/blood.2021015173 Get It

Abstract To determine the survival benefit of allogeneic hematopoietic cell transplantation (allo-HCT) in chronic myelomonocytic leukemias (CMML), we assembled a retrospective cohort of CMML patients 18-70 years old diagnosed between 2000 and 2014 from an international CMML dataset (n = 730) and the EBMT registry (n = 384). The prognostic impact of allo-HCT was analyzed through univariable and multivariable time-dependent models and with a multistate model, accounting for age, sex, CMML prognostic scoring system (low or intermediate-1 grouped as lower-risk, intermediate-2 or high as higher-risk) at diagnosis, and AML transformation. In univariable analysis, lower-risk CMMLs had a 5-year overall survival (OS) of 20% with allo-HCT vs 42% without allo-HCT (P &lt; .001). In higher-risk patients, 5-year OS was 27% with allo-HCT vs 15% without allo-HCT (P = .13). With multistate models, performing allo-HCT before AML transformation reduced OS in patients with lower-risk CMML, and a survival benefit was predicted for men with higher-risk CMML. In a multivariable analysis of lower-risk patients, performing allo-HCT before transformation to AML significantly increased the risk of death within 2 years of transplantation (hazard ratio [HR], 3.19; P &lt; .001), with no significant change in long-term survival beyond this time point (HR, 0.98; P = .92). In higher-risk patients, allo-HCT significantly increased the risk of death in the first 2 years after transplant (HR 1.46; P = .01) but not beyond (HR, 0.60; P = .09). Performing allo-HCT before AML transformation decreases life expectancy in lower-risk patients but may be considered in higher-risk patients.