Comparative Effectiveness of BNT162b2 and NVX-CoV2373 Vaccines in Korean Adults

Background Various types of vaccines against SARS-CoV-2 have reduced the burden of coronavirus diseases 2019 (COVID-19) across the world. We conducted an observational study to evaluate the effectiveness of NVX-CoV2373 and BNT162b2 in providing protection in Korean adults. Methods This study was a retrospective matched cohort study to emulate a target trial of three doses of NVX-CoV2373 (N-N-N) versus three doses of BNT162b2 (B-B-B) vaccines in presumed immune-naive adults. We used data from the Korea COVID-19 Vaccine Effectiveness (K-COVE) cohort, combining all COVID-19 laboratory-confirmed cases and all COVID-19 immunization registry, between February and November 2022. We calculated 40-week risk differences and risk ratios between the two vaccines. Results A total of 3,019 recipients of NVX-CoV2373 vaccine and 3,027 recipients of BNT162b2 vaccine were eligible for the study. The 40-week risk ratios for recipients of the NVX-CoV2373 vaccine as compared with recipients of the BNT162b2 vaccine were 1.169 (95% CI, 1.015 to 1.347) for laboratory-confirmed SARS-CoV-2 infection, and 0.504 (95% CI, 0.126 to 2.014) for severe SARS-CoV-2 infection. Estimated risk of severe infection was 0.001 events per 1000 persons (95% CI, 0 to 0.003) for the NVX-CoV2373 vaccine and 0.002 events per 1000 persons (95% CI, 0.001 to 0.006) for BNT162b2 vaccine. Conclusion This study identifies reduced risk of SARS-CoV-2 infection and severe infection after receipt of three doses of either NVX-CoV2373 or BNT162b2 vaccines in Korean adults. Direct, vaccine-conferred protection may be of importance among high risk persons to mitigate from serious clinical outcome from COVID-19. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study was conducted as a legally mandated public health investigation under the authority of the Korean Infectious Diseases Control and Prevention Act. The study was approved by the Korea Disease Control and Prevention Agency Institutional Review Board (IRB No. 2021-12-03-PE-A). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors.