104435 - Post-Authorization Safety Study (PASS) of Post-Marketing Surveillance for Intussusception Following Rotarix Introduction into the Instituto Mexicano del Seguro Social (IMSS) in Mexico

Study type

• Study topic:
  Disease /health condition

  Human medicinal product
• Study type:
  Non-interventional study
• Scope of the study:
  Assessment of risk minimisation measure implementation or effectiveness
• Data collection methods:
  Secondary use of data

Non-interventional study

• Non-interventional study design:
  Other
• Non-interventional study design, other:
  Self-controlled case series

Study drug and medical condition

• Name of medicine:
  ROTARIX
• Medical condition to be studied:
  Intussusception

Population studied

• Short description of the study population:
  Children younger than one year of age among Instituto Mexicano del Seguro Social (IMSS) members who has received Rotarix.
• Age groups:
  • Paediatric Population (< 18 years)

    • Neonate

      • Preterm newborn infants (0 – 27 days)
      • Term newborn infants (0 – 27 days)
    • Infants and toddlers (28 days – 23 months)
• Estimated number of subjects:
  789

Study design details

• Main study objective:
  To assess the temporal association between Rotarix administration and definite IS occurrence within 31 days (Day 0 to Day 30) following vaccination.
• Outcomes:
  Occurrence of definite IS episodes within Day 0 to Day 30 following vaccination. Occurrence of definite IS episodes within Day 0 to Day 15 following vaccination.Yearly occurrence of definite IS episodes (regardless of vaccination status).
• Data analysis plan:
  SCCS methodology with adjustment by one month age interval was used to assess temporal associations between Rotarix administration and IS.Risk periods: 30 days (primary) and 16 days (secondary objectives) risk period after each dose.Control period: started at 31 days after each Rotarix dose and continued up to one year of age.Alpha was adjusted similar to the O’Brien-Fleming adjustment. For an overall alpha of 0.05, the interim analysis was performed with an alpha of 0.01 while the final analysis was performed with an alpha of 0.045.Primary objective was considered reached if upper limit (UL) of 95.5% CI (alpha = 0.045) of the relative incidence (RI) of the IS episode after each Rotarix dose is less than the RI corresponding to the consensus risk estimate of Rotashield of 1/10 000: Dose 1 RI=2.67, Dose 2 RI=1.59.Yearly (2008-2010) incidence of IS, with its exact 95% CIs was calculated for the entire population <1 year of age with membership in the IMSS system.