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COVID-19

COVID-19 Vaccine Study Reveals Distinct Immune Responses Between Comirnaty and Vaxzevria

Strategic Insights

— 1 min read

Researchers at the Faculty of Medicine in Zabrze, Poland, have conducted a study comparing the immune responses of healthy individuals who received either Comirnaty (Pfizer) or Vaxzevria (AstraZeneca) vaccinations, with or without prior SARS-CoV-2 infection. The study analyzed 134 volunteers, with 71 recipients of Comirnaty (36 with prior infection) and 63 recipients of Vaxzevria (33 with prior infection). The findings highlight significant differences in immune responses between the two vaccines, with Comirnaty inducing a stronger T-cell-mediated response, especially after the third dose.

Key Takeaways:

  • The study compared the immune responses of healthy individuals who received Comirnaty (Pfizer) or Vaxzevria (AstraZeneca) vaccinations, with or without prior SARS-CoV-2 infection.
  • Significant differences were observed in IgG and IFN-g concentrations between the vaccine groups, with higher levels noted in individuals vaccinated with Comirnaty.
  • Prior infection enhanced immune responses, with previously infected individuals showing elevated IgG and IFN-g levels.
  • Hematological analysis revealed differences in immune activation patterns between vaccines, including variations in white blood cell counts, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR).
  • The study emphasizes the importance of booster doses in maintaining robust immunity against SARS-CoV-2.
  • The research contributes to understanding the differential immune memory elicited by mRNA-based and adenoviral vector-based vaccines.

Statistics:

  • 134 volunteers were analyzed in the study.
  • 71 recipients of Comirnaty received the vaccine (36 with prior SARS-CoV-2 infection).
  • 63 recipients of Vaxzevria received the vaccine (33 with prior SARS-CoV-2 infection).
  • Higher IgG levels were noted in individuals vaccinated with Comirnaty after the third dose (average increase: 43.6%).
  • Prior infection enhanced immune responses, with IFN-g levels increasing by 27.5% in previously infected individuals.
  • Differences in immune activation patterns were observed between vaccines, with variations in NLR (13.4% vs. 15.6%) and PLR (62.1% vs. 55.8%).

Sources:

  • "Comparison of SARS-CoV-2 immune responses following vaccination with Comirnaty (Pfizer) and Vaxzevria (AstraZeneca) in healthy individuals with or without prior SARS-CoV-2 infection." Frontiers in Immunology, 2025;16:1612288.
  • Frontiers in Immunology, Avenue Du Tribunal Federal 34, Lausanne, Ch-1015, Switzerland.
  • Medical Letter on the CDC & FDA, NewsRx, August 24, 2025; p 76.

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