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. 2025 Aug 1;8(8):e2536889.
doi: 10.1001/jamanetworkopen.2025.36889.

Risk of Myocarditis or Pericarditis With High-Dose vs Standard-Dose Influenza Vaccine: A Prespecified Secondary Analysis of the Randomized DANFLU-2 Trial

Manan Pareek  1   2 , Niklas Dyrby Johansen  1   2 , Daniel Modin  1   2 , Matthew M Loiacono  3 , Rebecca C Harris  4 , Marine Dufournet  5 , Carsten Schade Larsen  6   7   8 , Lykke Larsen  9 , Lothar Wiese  10 , Michael Dalager-Pedersen  11   12 , Brian L Claggett  13 , Kira Hyldekær Janstrup  1   2 , Katja Vu Bartholdy  1   2 , Katrine Feldballe Bernholm  1   2 , Julie Inge-Marie Helene Borchsenius  1   2 , Filip Søskov Davidovski  1   2 , Lise Witten Davodian  1   2 , Maria Dons  1   2 , Lisa Steen Duus  1   2 , Caroline Espersen  1   2 , Frederik Holme Fussing  1   2 , Anne Marie Reimer Jensen  1   2 , Nino Emanuel Landler  1   2 , Adam Cadovius Femerling Langhoff  1   2 , Mats Christian Højbjerg Lassen  1   2 , Anne Bjerg Nielsen  1   2 , Camilla Ikast Ottosen  1   2 , Morten Sengeløv  1   2 , Kristoffer Grundtvig Skaarup  1   2 , Scott D Solomon  13 , Martin J Landray  14 , Gunnar H Gislason  1   15   16   17 , Lars Køber  15   18 , Pradeesh Sivapalan  15   19 , Cyril Jean-Marie Martel  20 , Jens Ulrik Stæhr Jensen  15   19 , Tor Biering-Sørensen  1   2   18   21
Affiliations

Risk of Myocarditis or Pericarditis With High-Dose vs Standard-Dose Influenza Vaccine: A Prespecified Secondary Analysis of the Randomized DANFLU-2 Trial

Manan Pareek et al. JAMA Netw Open. .
No abstract available

Plain language summary

This prespecified secondary analysis of a randomized clinical trial investigates the risk of myocarditis or pericarditis with high-dose vs standard-dose inactivated influenza vaccine among older adults.

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Conflict of interest statement

Conflict of Interest Disclosures: Dr Pareek reported receiving personal fees from AstraZeneca, Bayer, Boehringer Ingelheim, Janssen-Cilag, and Novo Nordisk and grants from the Danish Cardiovascular Academy and Danish Heart Foundation outside the submitted work. Dr. Harris reported that as an employee of Sanofi, she may hold Sanofi shares outside the submitted work. Dr. Dufournet reported owning stock options from Sanofi outside the submitted work. Dr. Claggett reported receiving personal fees from Alnylam, Cardior, Cardurion, Cytokinetics, CVRx, Intellia, Rocket, Lilly, and Alexion outside the submitted work. Dr. Bartholdy reported receiving grants from the Danish Cardiovascular Academy outside the submitted work. Dr Langhoff reported receiving grants from the Novo Nordisk Foundation and personal fees from Novo Nordisk outside the submitted work. Dr. Skaarup reported receiving personal fees from Sanofi and AstraZeneca outside the submitted work. Dr. Solomon reported receiving grants from Alexion, Alnylam, Applied Therapeutics, AstraZeneca, Bellerophon, Bayer, Bristol Myers Squibb (BMS), Boston Scientific, Cytokinetics, Edgewise, Eidos/BridgeBio, Gossamer, GSK, Ionis, Lilly, the National Institutes of Health/National Heart, Lung, and Blood Institute, Novartis, Novo Nordisk, Respicardia, Sanofi Pasteur, Tenaya, Theracos, and US2.AI and personal fees from Abbott, Action, Akros, Alexion, Alnylam, Amgen, Arena, Askbio, AstraZeneca, Bayer, BMS, Bridgebio, Cardior, Cardurion, Corvia, Cytokinetics, GSK, Intellia, Lilly, Novartis, Roche, Theracos, Quantum Genomics, Tenaya, Sanofi Pasteur, Dinaqor, Tremeau, CellProThera, Moderna, American Regent, Sarepta, Lexicon, Anacardio, Akros, Valo, Synhale, and Recordati outside the submitted work. Dr Landray reported receiving grants from Moderna, Regeneron, GSK, Sanofi, Boehringer Ingelheim, and Novartis to the University of Oxford and Protas outside the submitted work. Dr Køber reported receiving personal fees from Novo Nordisk, Novartis, AstraZeneca, and Boehringer outside the submitted work. Dr Biering-Sørensen reported receiving grants from Sanofi for the DANFLU-2 trial during the conduct of the study and grants from Sanofi Pasteur, Novo Nordisk, Novartis, Pfizer, GSK, AstraZeneca, Boston Scientific, GE HealthCare, and Bayer and personal fees from Sanofi Pasteur, Novo Nordisk, Novartis, GSK, IQVIA, Parexel, Amgen, CSL Seqirus, AstraZeneca, Bayer, and GE HealthCare outside the submitted work.

Figures

Figure.
Figure.. Risk of Myocarditis or Pericarditis Among Patients Receiving High-Dose vs Standard-Dose Influenza Vaccine
HD-IIV indicates high-dose inactivated influenza vaccine; NA, not applicable; rVE, relative vaccine effectiveness; SD-IIV, standard-dose inactivated influenza vaccine.
See this image and copyright information in PMC

References

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