Secondary Safety Analysis of Different COVID-19 Vaccines and mRNA Products in a Cohort of 46 Million Participants in England

We performed a secondary safety analysis of different COVID-19 vaccines from several large UK data sets. The original published studies did not perform such analyses. We assessed confidence intervals of the ratio of hazard ratios for the following published studies: Ip et al (45.7M participants) [1], Whiteley et al (45.7M) [2], Horne et al (7.6M) [3], Parker et al (427K) [4], and Hulme et al (2.7M) [5]. Our analysis reveals extreme and verifiable increased hazards associated with the Oxford/AstraZeneca ChAdOx1 COVID-19 vaccine (“AstraZeneca Product”) relative to the Pfizer-BioNTech BNT162b2 COVID-19 mRNA product (“Pfizer Product”). Significant increased hazards for the AstraZeneca Product manifested in cardiovascular disease and death. Significant increased hazards for the Pfizer Product manifested in myocarditis and pericarditis. The published primary studies, performed during the active pandemic period, promoted the “cardiovascular safety” of the COVID-19 products. However, they neglected to compare relative safety between products, which would have revealed multiple signals contrary to that narrative. Our secondary study reveals increased hazards in each type of COVID-19 product that contradict prior safety claims. The subsequent removal of the AstraZeneca Product from the market and the now-universal recognition of myocarditis risk from the Pfizer Product are consistent with our findings. The primary studies reached false conclusions that were avoidable by making comparisons of the different products, raising concerns about investigational bias.