Systematic analysis of COVID-19 mRNA vaccines using four orthogonal approaches demonstrates no excessive DNA impurities

systematic-analysis-of-covid-19-mrna-vaccines-using-four-orthogonal-approaches-demonstrates-no-excessive-dna-impurities
Systematic analysis of COVID-19 mRNA vaccines using four orthogonal approaches demonstrates no excessive DNA impurities

Data availability

All data generated or analysed during this study are included in this published article and its supplementary information file. Unmodified short-read sequences were deposited in NCBI under Project ID PRJNA1303864 and are accessible via https://www.ebi.ac.uk/ena/browser/view/PRJNA1303864, or https://www.ncbi.nlm.nih.gov/bioproject/PRJNA1303864/.

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Acknowledgements

This work was funded by the Government of the Slovak Republic via the Ministry of Health of the Slovak Republic, and supported by the Slovak Academy of Sciences. We would like to thank the State Institute for Drug Control and Ministry of Health of the Slovak Republic for arranging the provision of vaccine samples from official repositories at UNIPHARMA and IMUNA PHARM. We are grateful to Roman Dorcik, Director of the State Institute for Drug Control, for his kind advises and support.The funder played no role in the study design, data collection, analysis and interpretation, or the writing of this manuscript.

Author information

Author notes

  1. These authors contributed equally: Tomas Szemes, Boris Klempa, Juraj Kopacek, Silvia Pastorekova.

Authors and Affiliations

  1. Biomedical Research Center, Slovak Academy of Sciences, Institute of Virology, Bratislava, Slovakia

    Adam Achs, Lukas Predajna, Maria Bartosova, Martina Melichercikova, Boris Klempa, Juraj Kopacek & Silvia Pastorekova

  2. Comenius University Science Park, Bratislava, Slovakia

    Tatiana Sedlackova, Jaroslav Budis, Diana Rusnakova & Tomas Szemes

  3. Biomedical Research Center, Slovak Academy of Sciences, Biotechnological and Analytical Laboratories, Sarisske Michalany, Slovakia

    Vladimir Zelnik, Marta Miklosova, Veronika Gencurova & Barbora Cernakova

Authors

  1. Adam Achs
  2. Tatiana Sedlackova
  3. Lukas Predajna
  4. Jaroslav Budis
  5. Maria Bartosova
  6. Vladimir Zelnik
  7. Diana Rusnakova
  8. Martina Melichercikova
  9. Marta Miklosova
  10. Veronika Gencurova
  11. Barbora Cernakova
  12. Tomas Szemes
  13. Boris Klempa
  14. Juraj Kopacek
  15. Silvia Pastorekova

Contributions

S.P., J.K., B.K., and T.Sz. designed the study, A.A., T.Se., L.P., M.B., V.Z., D.R., M.Me., M.Mi., V.G., and B.C. performed the experiments and/or data analysis, J.B. accomplished bioinformatic analysis of sequencing data, S.P. prepared the original manuscript, J.K., B.K., T.Sz., A.A., T. Se., L.P., and J.B. contributed to the writing, reviewing and editing the manuscript. S.P. and J.K. were involved in funding acquisition and project management. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Silvia Pastorekova.

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Competing interests

The authors declare no competing interests.

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Achs, A., Sedlackova, T., Predajna, L. et al. Systematic analysis of COVID-19 mRNA vaccines using four orthogonal approaches demonstrates no excessive DNA impurities. npj Vaccines (2025). https://doi.org/10.1038/s41541-025-01304-9

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  • DOI: https://doi.org/10.1038/s41541-025-01304-9