Durability analysis of the highly effective BNT162b2 vaccine against COVID-19

Abstract

SARS-CoV-2 breakthrough infections have been increasingly reported in fully vaccinated individuals. We conducted a test-negative case-control study to assess the durability of protection after full vaccination with BNT162b2, defined as 14 days after the second dose, against polymerase chain reaction (PCR)-confirmed symptomatic SARS-CoV-2 infection, in a national medical practice between February 1, 2021 and August 22, 2021. We fit conditional logistic regression (CLR) models stratified on residential county and calendar time of testing to assess the association between time elapsed since vaccination and the odds of symptomatic infection or non-COVID-19 hospitalization (negative control), adjusted for several covariates. The primary population included 652 individuals who had a positive symptomatic test after full vaccination with BNT162b2 (cases) and 5,946 individuals with at least one negative symptomatic test after full vaccination (controls). The adjusted odds of symptomatic infection were higher 120 days after full vaccination versus at the date of full vaccination (Odds Ratio [OR]: 3.21, 95% confidence interval [CI]: 1.33-7.74). Importantly, the odds of infection were still lower 150 days after the first BNT162b2 dose as compared to 4 days after the first dose (OR: 0.3, 95% CI: 0.19-0.45), when immune protection approximates the unvaccinated status. Low rates of COVID-19 associated hospitalization or death in this cohort precluded analyses of these severe outcomes. The odds of experiencing a non-COVID-19 hospitalization decreased with time since vaccination, suggesting a possible underestimation of waning protection by this approach due to confounding factors. Taken together, these data constitute an early signal for waning protection against symptomatic illness while also providing reassurance that BNT162b2 continues to protect against symptomatic SARS-CoV-2 infection several months after full vaccination. Continued surveillance of COVID-19 vaccine durability, particularly against severe disease, is critical to guide effective and equitable strategies to respond to the pandemic, including distribution of booster doses, development of new vaccines, and implementation of both pharmaceutical and nonpharmaceutical interventions.

Comparative effectiveness of mRNA-1273 and BNT162b2 against symptomatic SARS-CoV-2 infection

“…9 Further, there have been reports of reduced vaccine effectiveness over time and against emerging variants, resulting in more breakthrough infections, which have spurred discussions regarding strategies to boost and prolong immunity in previously vaccinated individuals. [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] With ongoing efforts to distribute initial vaccination series throughout the world and booster doses in the United States and elsewhere, it is important to understand whether one mRNA vaccine confers stronger protection than the other. Here, we begin to address this knowledge gap by retrospectively comparing the rates of symptomatic SARS-CoV-2 infection after full vaccination with mRNA-1273 versus BNT162b2 in the multi-state Mayo Clinic Health System.…”

“…Indeed, we and others have recently found that protection against SARS-CoV-2 infection wanes over time after full vaccination with BNT162b2, and a similar trend has been suggested for mRNA-1273. 16,17,[19][20][21]28,29 Several factors could contribute to the observed differences in effectiveness of mRNA-1273 and BNT162b2. Although both are nucleoside-modified mRNA vaccines encoding the prefusion stabilized SARS-CoV-2 Spike protein, there are differences in the vaccination regimen and formulation.…”

Timely Monitoring COVID-19 Vaccine Protection, Berlin, Germany, April 15th to December 15th, 2021

“…Third, since mid-August, the VP constantly decreased from around 84% in August to around 60% in November. This probably signals waning immunity [ 9 , 12 , 13 ]. Time since vaccination is systematically longer for older age groups ( Figure 2 ), potentially increasing the effect of waning immunity visible in our data.…”

Interplay between risk perception, behaviour, and COVID-19 spread

“…Our model includes the effect of vaccination, where vaccines are for simplicity administered with a singledosage delivery scheme. Vaccinated individuals cannot be infected while being in the vaccinated compartment, but will proceed to the waned immunity compartment W v at a rate Ω [52,53]. The same applies to recovered individuals, who also lose their post-infection immunity at rate Ω [54].…”