Effectiveness of heterologous and booster Covid-19 vaccination in 5 European countries, using a cohort approach in children and adults with a full primary Covid-19 vaccination regimen (Covid Vaccines Effectiveness (CoVE))

Study type

• Study topic:
  Disease /health condition

  Human medicinal product
• Study type:
  Non-interventional study
• Scope of the study:
  Effectiveness study (incl. comparative)
• Data collection methods:
  Secondary data collection

Non-interventional study

• Non-interventional study design:
  Cohort

  Other
• Non-interventional study design, other:
  Retrospective multi-database study

Study drug and medical condition

• Anatomical Therapeutic Chemical (ATC) code:
  (J07BX03) covid-19 vaccines
• Medical condition to be studied:
  SARS-CoV-2 test positive
• Additional medical condition(s):
  Severe Covid-19 (i.e. admitted to hospital or intensive care units) Covid-19-related death, all Covid-19 infections, all-cause mortality (secondary objective)

Population studied

• Short description of the study population:
  The study population comprised of all children, adolescents, and adults, had at least 2 years of available healthcare data registered in the 6 electronic health care databases for the study period of December 2020 to February 2022.; The study also included vaccinated individuals with at least two recorded vaccinations since the start of the study period.
• Age groups:
  Children (2 to < 12 years)

  Adolescents (12 to < 18 years)

  Adults (18 to < 46 years)

  Adults (46 to < 65 years)

  Adults (65 to < 75 years)

  Adults (75 to < 85 years)

  Adults (85 years and over)
• Special population of interest:
  Other
• Special population of interest, other:
  COVID-19 patients
• Estimated number of subjects:
  67271319

Study design details

• Main study objective:
  The goal of this study is to assess the effectiveness and waning of immunity of primary Covid-19 vaccinations and the booster in preventing different covid-19 outcomes.
• Outcomes:
  covid-19 (positive test and/or diagnosis) severe covid-19 covid-19 related death, all-cause mortality
• Data analysis plan:
  Distributions of baseline and Covid-19 vaccination characteristics at time0 will be assessed in all-Covid-19 vaccinated population and matched populations. Incident rates differences (95% confidence intervals) of each Covid-19 outcome for both primary vaccination matched and booster/non-booster matched cohorts estimated by overall, age groups, brands, and time since (booster-)time0 will be estimated. IPW-weight Kaplan-Meier curves will be generated to depict the cumulative incidence of the outcomes by matched cohorts over time after (booster-)time0. Cox proportional hazards regression (95% confidence intervals) to derive the average hazard ratio (HR) of Covid-19 related outcomes will be produced. The adjusted vaccine effectiveness for all the outcomes and all-cause death will be estimated as 1 minus the adjusted HR (and 1-95% confidence intervals) for age groups, overall matched cohorts, and brands.Random-effects meta-analyses will be performed in subpopulations reduced in number.

Documents

Study, other information

ROC12_CoVE_Abstract