Effectiveness Over Time of a Primary Series of the Original Monovalent COVID-19 Vaccines in Adults in the United States

With data from 2 US claims databases (Optum, CVS Health) supplemented with Immunization Information System COVID 19 vaccine records, we evaluated overall and time-specific vaccine effectiveness (VE) of an initial primary series for 3 monovalent COVID 19 vaccines—BNT162b2, mRNA-1273, and JNJ-7836735—in adults (18-64 years). Vaccinated individuals were matched to unvaccinated comparators, and we estimated VE against any medically diagnosed COVID 19 and hospital/emergency department (ED)-diagnosed COVID 19. Additionally, we estimated VE by era of predominant variants, in subgroups, and compared across vaccine brands. The cohorts consisted of 341,097 (Optum) and 1,151,775 (CVS Health) matched pairs for BNT162b2; 201,604 (Optum) and 651,545 (CVS Health) for mRNA-1273; and 49,285 (Optum) and 149,813 (CVS Health) for JNJ-7836735. Summary VE estimates from meta-analysis against hospital/ED-diagnosed COVID 19 were: BNT162b2, 77% (95% CI, 76%-78%); mRNA-1273, 84% (95% CI, 83%-85%), JNJ-7836735 66% (95% CI, 63%-68%). VE estimates were higher for hospital/ED-diagnosed COVID 19 than for medically diagnosed COVID-19, and VE estimates were highest in adults receiving mRNA-1273 for both outcomes. VE was sustained for approximately 7 months for medically-diagnosed and up to 9 months for hospital/ED-diagnosed COVID 19. VE differed by brand and variant era. Additional real-world research is needed as new variants and recommendations for updated vaccines have evolved.