Received: 18 April 2022 Revised: 23 May 2022 Accepted: 26 May 2022 DOI: 10.1002/ajh.26626 CORRESPONDENCE Outcome of infection with omicron SARS-CoV-2 variant in patients with hematological malignancies: An EPICOVIDEHA survey report To the Editor: calculation was not applied in this exploratory study. SPSSv25.0 was Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infec- employed for statistical analyses (SPSS, IBM Corp.). tion has caused high mortality in patients with hematological malig- In total 593 HM patients infected with omicron were included, nancies (HM).1 The newly emerged omicron variants of SARS-CoV-2 whereof 309 patients were admitted to hospital and 284 patients stayed harbor multiple novel spike protein mutations that raise concerns home (eTable 1). Hospitalized patients were older than nonhospitalized about vaccine efficiency and antiviral efficacy of the available thera- patients, had more comorbidities, and had a higher proportion of 2 peutic monoclonal antibodies. The first published clinical data in patients with neutropenia, lymphocytopenia, active hematological malig- immunocompetent patients have found that infection with omicron nancy, and treatment with anti-CD20 antibodies (eTable 1). At least one variants is associated with reduced vaccine efficiency compared to dose of vaccine had been administered to 83.1% of all patients, with a the delta variants, but decreased hospital admission and mortality.3,4 nonsignificant difference between nonhospitalized and hospitalized Preliminary, prepublished, data from a large case–control study have patients, 86.3% compared to 80.3% (p = .157) (eTable 1, eTable 2). shown that the vaccine effect against omicron in immunocompro- Overall mortality among hospitalized patients was 16.5% mised patients, including HM patients, is even more reduced, but data (51/309), of which 61% was classified as attributable to omicron, regarding clinical outcomes are lacking.5 The aim of this study was to 35.3% contributable, and 3.9% unrelated. Factors associated with describe risk factors, antiviral treatment and outcomes of SARS- attributable and contributable mortality in hospitalized patients were CoV-2 omicron variant infection in 593 HM patients included in the older age (analyzed as continuous variable, hazard ratio (HR) 1.05 EPICOVIDEHA registry. (95% confidence interval (CI) 1.02–1.07, p < .001]) and active malig- EPICOVIDEHA is an international open web-based registry for nancy (HR 2.5 [95% CI 1.3–4.8, p = .007]) (Table 1). Having received 1,6 patients with HM infected with SARS-CoV-2. Both hospitalized and at least one dose of SARS-CoV-2 vaccine was protective in univari- nonhospitalized patients are eligible for inclusion. The questionnaire able analysis (HR 0.53 [95% CI 0.29–0.96, p = .036]), but did not includes data on the HM, SARS-CoV-2 vaccination status, risk factors reach statistical significance in multivariable analysis (HR 0.58 [95% CI for severe COVID-19 infection, SARS-CoV-2 virus variant, antiviral 0.32–1.05, p = .074]) (eFigure 2a, Table 1). treatment, and outcomes including mortality (eFigure 1 and eTable 4). Progression to critical infection occurred in 53 (17.0%) of hospi- Classification of attributable, contributable, or nonattributable death talized patients. Risk factor for progression to critical COVID-19 was is made by the reporting physician. All included cases are validated by pre-existent chronic pulmonary disease (odds ratio (OR) 3.2 [95% CI experts with previous experience in research studies of hematological 1.4–7.3, p = .005]) (eTable 3). Baseline lymphocytes of ≥500 cells/ malignancies and infectious diseases at the University Hospital mm3 were protective (OR 0.4 [95% CI 0.18–0.90, p = .027]) while a Cologne, Cologne, Germany. lymphocyte count between 200 and 499 cells/mm3 was protective in Critical infection was defined as admittance to an intermediate uni- but not multivariable analysis (OR 0.44 [95% CI 0.16–1.20, and/or intensive care unit. Independent predictors for mortality were p = .108]). Three doses of vaccine were protective (OR 0.29 [95% CI assed via a Cox proportional hazard model. Risk factors for critical 0.13–0.64, p = .003]), but not two doses (OR 0.73 [95% CI 0.33– SARS-CoV-2 infection were determined with a logistic regression. 1.66, p = .457] (eTable 3). Mortality among patients with critical infec- Variables with a p-value ≤.1 in the univariable models were consid- tion was 39.2% (20/53). Administration of antibody-based antiviral ered for multivariable analysis. Multivariable regression models (both treatment with sotrovimab or tixagevimab/cilgavimab was associated Cox and logistic) were calculated with the Wald backward method, with a lower risk for mortality in critical infection (HR 0.13, [95% CI and only those variables that were statistically significant displayed. 0.02–0.61, p = .010]) (eFigure 2b, Table 1), while administration of Log-rank test was used to compare the survival probability of the other SARS-CoV-2 directed monoclonal antibodies was not (data not patients included in the different models. A priori sample size shown). This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. © 2022 The Authors. American Journal of Hematology published by Wiley Periodicals LLC. E312 wileyonlinelibrary.com/journal/ajh Am J Hematol. 2022;97:E312–E317. TABLE 1 Risk factor analysis for omicron-related mortality in hospitalized patients Hospital CORRESPONDENCE Overall Critical Univariable Multivariable Univariable Multivariable 95% CI 95% CI 95% CI 95% CI p p value HR Lower Upper value HR Lower Upper p value HR Lower Upper p value HR Lower Upper Sex Female — — — — — — — — Male .609 0.866 0.500 1.501 .800 0.894 0.377 2.124 Age <.001 1.047 1.022 1.072 <0.001 1.044 1.020 1.068 0.134 1.029 0.991 1.069 Status of malignancy at COVID-19 onseta Controlled malignancy — — — — — — — — — — — — — — — — Stable malignancy 0.348 1.526 0.632 3.684 0.668 1.215 0.499 2.957 0.014 4.780 1.370 16.676 0.003 8.230 2.026 33.439 Active malignancy 0.003 2.726 1.421 5.229 0.007 2.473 1.284 4.762 0.088 2.511 0.871 7.240 0.055 2.887 0.977 8.529 Baseline malignancy Lymphoproliferative malignancies — — — — — — — — Myeloproliferative malignancies 0.508 0.798 0.409 1.556 0.758 1.153 0.465 2.862 Aplastic anemia 0.974 0.000 0.000 Previous SARS-CoV-2 vaccination 0.036 0.530 0.293 0.959 0.074 0.581 0.320 1.054 0.592 0.780 0.314 1.934 b COVID-19 treatment No treatment — — — — — — — — — — — — Any remdesivir, minus sotrovimab 0.857 0.941 0.487 1.817 0.953 0.967 0.314 2.975 0.200 0.452 0.134 1.521 Any sotrovimab + any tixagevimab/ 0.134 0.531 0.232 1.216 0.021 0.172 0.039 0.766 0.010 0.134 0.029 0.614 cilgavimab Plasma only + molnupiravir only 0.639 1.330 0.404 4.377 0.776 1.242 0.280 5.513 0.604 1.491 0.330 6.738 Previous administration of antiCD20 0.760 1.090 0.626 1.898 0.187 0.528 0.205 1.363 Abbreviations: 95% CI, 95% confidence interval; COVID-19, coronavirus disease 2019, HR, hazard ratio; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2. a Controlled malignancy: Complete remission or partial remission; active malignancy: onset or refractory/resistant. b No treatment: Includes treatment with acyclovir, favipiravir, casivirimab/imdevimab, bamlanvimab/etesivimab and regdanvimab; Any remdesivir, minus sotrovimab: Includes all antiviral treatment which included remdesivir except for sotrovimab and tixagevimab/cilgavimab; Any sotrovimab + any tixagevimab/cilgavimab: Includes all antiviral treatment which included sotrovimab or tixagevimab/cilgavimab; Plasma only + molnupiravir only: Includes single therapy with convalescent plasma or molnupiravir. E313 E314 CORRESPONDENCE This observational study from the EPICOVIDEHA registry is the at least three doses was protective against progression to critical first report on clinical data in a large cohort of omicron-infected HM infection, and treatment with monoclonal antibodies was associated patients. The main finding is that infection with omicron is associated with reduced mortality in patients that had progressed to critical with considerable attributable mortality in HM patients. Additionally, infection. we found factors associated with a potential antibody response, that is, not having severe lymphocytopenia and having received at least FUNDING INF ORMATI ON three doses of SARS-CoV-2 vaccine, and treatment with monoclonal EPICOVIDEHA has received funds from Optics COMMIT (COVID-19 antibodies with in vitro effect against omicron, to be protective Unmet Medical Needs and Associated Research Extension) COVID-19 against progression to critical infection and death. RFP program by GILEAD Science, United States (Project 2020-8223). The mortality among hospitalized HM patients was 16.5% which is lower than during the COVID-19 waves of 2020 and 2021, but con- CONFLIC T OF INT ER E ST siderable higher than previously reported mortality rates in immuno- The authors declare that they have no competing interests for competent patients with omicron infection.1,3,4 Data regarding this work. outcomes in HM patients with omicron are scarce, but our finding is in agreement with a small recent preliminary report on omicron in DATA AVAILABILITY STAT EMEN T chronic lymphoid leukemia patients, where 23% 30-day mortality was The datasets used and/or analyzed during the current study are not reported.7 Thus, as opposed to immunocompetent patients, infection publicly available due to individual privacy reason, but are available with omicron in HM patients is still associated with a considerable from the corresponding author on reasonable request. mortality in hospitalized patients. Due to serological data not being registered consistently by all FUNDING INF ORMATI ON participating centers, the protective effect of vaccination was ana- Optics COMMIT (COVID-19 Unmet Medical Needs and Associated lyzed according to number of doses administrated. For the whole Research Extension) COVID-19 RFP program by GILEAD Science, cohort, the vaccination rate was numerically higher in non- United States, Grant/Award Number: Project 2020-8223 hospitalized patients than hospitalized patients, 86.3% compared to 80.3%, respectively. Administration of at least one dose of vaccine Ola Blennow1 , Jon Salmanton-García2,3 , Piotr Nowak1 , was protective against death in all hospitalized patients in univariable pez-García6 Federico Itri4 , Jaap Van Doesum5 , Alberto Lo , analysis but not in multivariable analysis (p = .074). Three doses of Francesca Farina 7 , Ozren Jaksic 8  Imre Pinczés , Lászlo 9 , vaccine were protective against progression to critical infection in Yavuz M. Bilgin10 , Iker Falces-Romero11,12 , hospitalized patients, while two doses were not, a finding that is well Moraima Jiménez13,14 , Irati Ormazabal-Vélez15 , in line with the additional booster effect against omicron in immuno- Barbora Weinbergerová16 , Rémy Duléry17 , competent patients.3,8 Interestingly, lymphocytopenia, which has been 18 19 20 Zlate Stojanoski , Tobias Lahmer , Noemí Fernández , José- associated with a poor vaccine response, was also associated with Ángel Hernández-Rivas21, Verena Petzer22 , Nick De Jonge23 , progression to critical infection.9 Finally, among patients that pro- Andreas Glenthøj 24  n25,26 , Cristina De Ramo , gressed to critical infection, vaccination was not associated with a pro- Monika M. Biernat27 , Nicola Fracchiolla28 , Avinash Aujayeb29 tective effect against death, contrary to treatment with monoclonal , Jens Van Praet30 , Martin Schönlein31 , antibodies with in vitro effect against omicron.2 These findings raise 32 Gustavo-Adolfo Méndez , Chiara Cattaneo33 , Anna Guidetti34, the hypothesis that while vaccination appears to be protective against Mariarita Sciumè28 , Emanuele Ammatuna5 , Raul Cordoba6 , severe infection and death, lack of response, as manifested by n35 Nicole García-Pouto , Stefanie Gräfe2,3,36 , progression to critical infection despite vaccination, may be at least in 13,14 22 1 Alba Cabirta , Dominik Wolf , Anna Nordlander , part compensated by passive immunization using SARS-CoV- n García-Sanz25,26 Ramo , Mario Delia37 , Caroline Berg 2-antagonizing monoclonal antibodies. This hypothesis is in line with Venemyr24 , Clara Brones38 , Roberta Di Blasi39 , Elizabeth De the findings from a large, randomized treatment study, reporting sig- Kort40 , Stef Meers41 , Sylvain Lamure42 , Laura Serrano43 , nificantly decreased mortality with administration of monoclonal anti- Maria Merelli 44 , Nicola Coppola 45 , Rui Bergantim 46 , bodies in hospitalized seronegative immunocompetent patients.10 Caroline Besson38 , Milena Kohn38 , Jessica Petiti47 , Important limitations of our study include the retrospective Carolina Garcia-Vidal35 , Michelina Dargenio48 , observational design and the accompanying risk for selection bias at François Danion49 , participating sites, lack of serological data, and lack of sequencing data Marina Machado 50 , Rebeca Bailén-Almorox 51 , which would enable distinction between the different omicron vari- Martin Hoenigl52,53,54 , Giulia Dragonetti55 , Louis Yi Ann Chai56, ants. Due to these limitations, caution must be taken in interpretation Chi Shan Kho57, Matteo Bonanni55,58, Raphaël Liévin39 , and generalization of the results. Francesco Marchesi59 , Oliver A. Cornely2,3,60,61,62 , In conclusion, infection with omicron in patients with HM was 55,58 Livio Pagano associated with considerable morbidity and mortality, vaccination with CORRESPONDENCE E315 1 Department of Infectious Diseases, Karolinska University Hospital, 26 n del Cáncer-IBMCC (USAL-CSIC), IBSAL, Centro de Investigacio Stockholm, Sweden Salamanca, Spain 2 27 Faculty of Medicine and University Hospital Cologne, Department I of Department of Haematology, Blood Neoplasms, and Bone Internal Medicine, Excellence Center for Medical Mycology (ECMM), Marrow Transplantation, Wroclaw Medical University, Wroclaw, University of Cologne, Cologne, Germany Poland 3 28 Faculty of Medicine and University Hospital Cologne, Cologne Excellence Hematology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Cluster on Cellular Stress Responses in Aging-Associated Diseases Policlinico, Milan, Italy 29 (CECAD), University of Cologne, Cologne, Germany Respiratory Department, Northumbria Healthcare, Newcastle, UK 4 30 Department of Clinical and Biological Sciences, San Luigi Gonzaga Department of Nephrology and Infectious diseases, AZ Sint-Jan Hospital – Orbassano, Orbassano, Italy Brugge-Oostende AV, Brugge, Belgium 5 31 Department of Hematology, University Medical Center Groningen, Department of Oncology, Hematology and Bone Marrow Groningen, The Netherlands Transplantation with Section of Pneumology, University Medical Center 6 Health Research Institute IIS-FJD, Fundacion Jimenez Diaz University Hamburg-Eppendorf, Hamburg, Germany 32 Hospital, Madrid, Spain Servicio de Infectología y Control de Infecciones, Hospital Escuela de 7 U.O. Ematologia e Trapianto Midollo, Dipartimento di Oncologia Istituto Agudos Dr. Ram on Madariaga, Posadas, Misiones, Argentina 33 Scientifico San Raffaele, Milan, Italy Hematology Unit, ASST-Spedali Civili, Brescia, Italy 8 34 Department of Hematology, University Hospital Dubrava, Zagreb, Division of Hematology and Bone Marrow Transplantation, Fondazione Croatia IRCCS Istituto Nazionale dei Tumori, Milan, Italy 9 35 Division of Hematology, Department of Internal Medicine, Faculty of Department of Infectious Diseases, Hospital Clinic de Barcelona, Medicine, University of Debrecen, Debrecen, Hungary University of Barcelona, IDIBAPS, Barcelona, Spain 10 36 Department of Internal Medicine/Hematology, ADRZ, Goes, Department of Oncology, Hematology, and Bone Marrow Netherlands Transplantation with Section of Pneumology, Universitätsklinikum 11 Microbiology and Parasitology Department, University Hospital La Paz, Hamburg Eppendorf, Hamburg, Germany 37 Madrid, Spain Hematology and Stem Cell Transplantation Unit, AOUC Policlinico, 12 CIBERINFEC, Instituto de Salud Carlos III, Madrid, Spain Bari, Italy 13 38 Department of Hematology, Vall d'Hebron Hospital Universitari, Service d'Hématologie, Centre Hospitalier de Versailles, Le Chesnay, Experimental Hematology, Vall d'Hebron Institute of Oncology (VHIO), France 39 Vall d'Hebron Barcelona Hospital Campus, Barcelona, Spain Hemato-Oncology Department, Hopital Saint Louis, Paris, France 14 40 Departament de Medicina, Universitat Autònoma de Barcelona, Department of Hematology, Radboud University Medical Center, Bellaterra, Spain Nijmegen, The Netherlands 15 41 Department of Haematology, Complejo Hospitalario de Navarra, Department Oncology, AZ KLINA, Brasschaat, Belgium 42 Pamplona, Spain Department of Clinical Hematology, Montpellier University Hospital, 16 Department of Internal Medicine, Hematology and Oncology, Masaryk IGMM UMR5535 CNRS, University of Montpellier, Montpellier, France University and University Hospital Brno, Brno, Czech Republic 43 n, Deparment of Hematology, Hospital Universitario de Cabueñes, Gijo 17 INSERM UMRs 938, Service d'Hématologie Clinique et de Thérapie Spain 44 Cellulaire, Hôpital Saint Antoine, AP-HP, Sorbonne Université, Paris, Infectious Diseas Clinic, ASU FC Udine Hospital, Udine, Italy 45 France Department of Mental Health and Public Medicine, Universitry of 18 University Clinic for Hematology, Medical Faculty, Ss Cyril and Campania, Naples, Italy 46 Methodius University of Skopje, Skopje, North Macedonia Department of Hematology, Centro Hospitalar e Universitário de São 19 Medizinische Klinik II, Klinikum rechts der Isar, TU München, Munich, João, Porto, Portugal 47 Germany Department of Clinical and Biological Sciences, University of Turin, 20 Department of Hematology, Hospital Universitario Marqués de Turin, Italy Valdecilla, Santander, Spain 48 Hematology and Stem Cell Transplant Unit, "Vito Fazzi" Hospital, 21 Deparment of Hematology, Hospital Universitario Infanta Leonor, Lecce, Italy 49 Madrid, Spain Department of Infectious Diseases, CHU de Strasbourg, Strasbourg, 22 Department of Hematology and Oncology, Medical University of France 50 Innsbruck, Innsbruck, Austria Clinical Microbiology and Infectious Diseases Department, Hospital 23 Department of Hematology, Cancer Center Amsterdam, Amsterdam General Universitario Gregorio Marañ on, Madrid, Spain 51 UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands Department of Hematology and Hemotherapy, Hospital General 24 Department of Hematology, Copenhagen University Hospital Universitario Gregorio Marañ on, Madrid, Spain 52 Rigshospitalet, Copenhagen, Denmark Division of Infectious Diseases and Global Public Health, Department of 25 Hematology Department, Hospital Universitario de Salamanca, Medicine, University of California San Diego, San Diego, California, USA Salamanca, Spain E316 CORRESPONDENCE 53 Clinical and Translational Fungal-Working Group, University of n Cristina De Ramo https://orcid.org/0000-0002-8167-6410 California San Diego, La Jolla, California, USA Monika M. Biernat https://orcid.org/0000-0002-5812-8520 54 Nicola Fracchiolla https://orcid.org/0000-0002-8982-8079 Division of Infectious Diseases, Department of Internal Medicine, Medical University of Graz, Graz, Austria Avinash Aujayeb https://orcid.org/0000-0002-0859-5550 55 Jens Van Praet https://orcid.org/0000-0002-7125-7001 Hematology Unit, Fondazione Policlinico Universitario Agostino Gemelli – IRCCS, Rome, Italy Martin Schönlein https://orcid.org/0000-0002-1010-0975 56 Gustavo-Adolfo Méndez https://orcid.org/0000-0003-0514-7004 National University Health System, University Medicine Center, Division of Infectious Diseases, Singapore Chiara Cattaneo https://orcid.org/0000-0003-0031-3237 57 Mariarita Sciumè https://orcid.org/0000-0001-7958-4966 Pamela Youde Nethersole Eastern Hospital, Hong Kong, Hong Kong SAR Emanuele Ammatuna https://orcid.org/0000-0001-8247-4901 58 Raul Cordoba https://orcid.org/0000-0002-7654-8836 Hematology Unit, Università Cattolica del Sacro Cuore, Rome, Italy 59 Hematology and Stem Cell Transplant Unit, IRCCS Regina Elena n Nicole García-Pouto https://orcid.org/0000-0002-0675-2241 National Cancer Institute, Rome, Italy Stefanie Gräfe https://orcid.org/0000-0001-7678-0179 60 Alba Cabirta https://orcid.org/0000-0001-7198-8894 Faculty of Medicine and University Hospital Cologne, Clinical Trials Centre Cologne (ZKS Köln), University of Cologne, Cologne, Germany Dominik Wolf https://orcid.org/0000-0002-4761-075X 61 Faculty of Medicine and University Hospital Cologne, Center for n García-Sanz Ramo https://orcid.org/0000-0003-4120-2787 Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Mario Delia https://orcid.org/0000-0002-6486-8912 Germany Caroline Berg Venemyr https://orcid.org/0000-0003-2461-5395 62 Clara Brones https://orcid.org/0000-0002-0971-5075 German Centre for Infection Research (DZIF), Partner Site Bonn-Cologne, Cologne, Germany Roberta Di Blasi https://orcid.org/0000-0001-9001-573X Elizabeth De Kort https://orcid.org/0000-0003-0125-9543 Correspondence Stef Meers https://orcid.org/0000-0003-1754-2175 Jon Salmanton-García, Faculty of Medicine and University Hospital Sylvain Lamure https://orcid.org/0000-0001-5980-305X Cologne, Department I of Internal Medicine, Excellence Center for Laura Serrano https://orcid.org/0000-0002-0931-1791 Medical Mycology (ECMM), University of Cologne, Cologne, Maria Merelli https://orcid.org/0000-0003-3907-5264 Germany, Nicola Coppola https://orcid.org/0000-0001-5897-4949 Email: jon.salmanton-garcia@uk-koeln.de Rui Bergantim https://orcid.org/0000-0002-7811-9509 Caroline Besson https://orcid.org/0000-0003-4364-7173 Ola Blennow and Jon Salmanton-García contributed equally to this Milena Kohn https://orcid.org/0000-0003-1438-3391 study. Jessica Petiti https://orcid.org/0000-0001-8640-2462 Carolina Garcia-Vidal https://orcid.org/0000-0002-8915-0683 Michelina Dargenio https://orcid.org/0000-0003-0924-4629 ORCID François Danion https://orcid.org/0000-0003-3907-0658 Ola Blennow https://orcid.org/0000-0002-7167-7882 Marina Machado https://orcid.org/0000-0002-8370-2248 Jon Salmanton-García https://orcid.org/0000-0002-6766-8297 Rebeca Bailén-Almorox https://orcid.org/0000-0003-2838-1776 Piotr Nowak https://orcid.org/0000-0003-2747-0734 Martin Hoenigl https://orcid.org/0000-0002-1653-2824 Federico Itri https://orcid.org/0000-0002-3532-5281 Giulia Dragonetti https://orcid.org/0000-0003-1775-6333 Jaap Van Doesum https://orcid.org/0000-0003-0214-3219 Raphaël Liévin https://orcid.org/0000-0002-5097-591X pez-García Alberto Lo https://orcid.org/0000-0002-5354-5261 Francesco Marchesi https://orcid.org/0000-0001-6353-2272 Francesca Farina https://orcid.org/0000-0002-5124-6970 Oliver A. Cornely https://orcid.org/0000-0001-9599-3137 Ozren Jaksic https://orcid.org/0000-0003-4026-285X Livio Pagano https://orcid.org/0000-0001-8287-928X  Imre Pinczés Lászlo https://orcid.org/0000-0003-0453-1709 Yavuz M. Bilgin https://orcid.org/0000-0003-4854-5424 RE FE RE NCE S Iker Falces-Romero https://orcid.org/0000-0001-5888-7706 1. Pagano L, Salmanton-Garcia J, Marchesi F, et al. COVID-19 infection Moraima Jiménez https://orcid.org/0000-0003-1444-8562 in adult patients with hematological malignancies: a European Hema- tology Association survey (EPICOVIDEHA). J Hematol Oncol. 2021; Irati Ormazabal-Vélez https://orcid.org/0000-0003-1141-5546 14(1):168. Barbora Weinbergerová https://orcid.org/0000-0001-6460-2471 2. Bruel T, Hadjadj J, Maes P, et al. Serum neutralization of SARS-CoV-2 Rémy Duléry https://orcid.org/0000-0002-5024-1713 omicron sublineages BA.1 and BA.2 in patients receiving monoclonal Zlate Stojanoski https://orcid.org/0000-0001-7502-8356 antibodies. 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