Layton JB, Peetluk LS, Lloyd PC, Jiao Y, Djibo DA, Deng J, Gruber JF, Ogilvie RP, Parambi R, Miller M, Song J, Weatherby LB, Bell EJ, Lo AC, Hervol JR, Wernecke M, Cho S, Wong H-L, Clarke TC, Bui CL, Stone A, Tarazi W, Deshazo J, Forshee RA, Anderson SA, Seeger JD, Amend KL, MaMahill-Walraven CN, Chillarige Y, Yang GW, Anthony MS, Shoaibi A. Effectiveness over time of a complete primary series of the original, monovalent COVID-19 vaccines among adults aged 18-64 years in the United States. Poster presented at the 2024 ISPE Annual Meeting; August 27, 2024. Berlin, Germany.

BACKGROUND: Although several COVID-19 vaccines are approved or authorized in the United States (US), early real-world studies have shown waning vaccine effectiveness (VE) against SARS-CoV-2 infection over time. Changes in circulating variants may also complicate assessments of waning VE over time.

OBJECTIVES: We evaluated the overall VE and VE over time of receiving a complete primary series for the first 3 US-approved/authorized monovalent COVID-19 vaccines—BNT162b2 (Pfizer-BioNTech), mRNA-1273 (Moderna), and JNJ-7836735 (Janssen)—in adults (18-64 years).

METHODS: Using data from 2 US health insurance claims databases (Optum, CVS Health) and Immunization Information Systems (study period 11 December 2020 to 15 January 2022 [Optum] and 11 December 2020 to 31 March 2022 [CVS Health]), we identified vaccinated individuals at their first dose and matched them to unvaccinated comparators on calendar date and personal characteristics to reduce selection bias, immortal person-time bias, and confounding. Follow-up began on the dose 1 or matching date; the vaccinated group was censored if they failed to receive a complete primary series. We estimated VE overall and by time since vaccination with 95% confidence intervals (CIs) against COVID-19 diagnosis from any medically attended setting, or specifically from a hospital/emergency department (ED). Analyses were performed separately by data source and meta-analyzed. We also estimated VE in different variant eras (pre-Delta, Delta, Omicron), and compared VE between vaccine brands.

RESULTS: The cohorts consisted of 341,097 (Optum) and 1,151,775 (CVS) matched pairs for BNT162b2; 201,604 (Optum) and 651,545 (CVS) for mRNA-1273; and 49,285 (Optum) and 149,813 (CVS) for JNJ-7836735. Meta-analyzed overall VE estimates against medically diagnosed and hospital/ED-diagnosed (respectively) COVID-19 for BNT162b2 were 50% (95% CI, 50%-51%) and 77% (95% CI, 76%-78%); for mRNA-1273, 59% (95% CI, 58%-60%) and 84% (95% CI, 83%-85%); and for JNJ-7836735, 38% (95% CI, 36%-40%) and 66% (95% CI, 63%-68%). VE estimates were generally sustained for approximately 200 days for medically diagnosed COVID-19 and 300 days for hospital/ED-diagnosed COVID-19 before waning. Overall VE estimates were highest for mRNA-1273, and era-specific VE was lowest during the Omicron era.

CONCLUSIONS: Observed VE estimates for all brands indicated the vaccines were protective against COVID-19 and that effectiveness was sustained for at least 7 months. VE estimates were higher for hospital/ED-diagnosed COVID-19 than for any medically diagnosed COVID-19 and were highest in adults receiving mRNA-1273. In the rapidly changing dynamics of the COVID-19 pandemic, additional real-world research is needed as new variants emerge and vaccines are updated.