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Extra-ordinary review process

Extra-ordinary review process


Extra-ordinary review

If serious problems arise with a prequalified product that may put vaccine potency at risk, the IMD-PQS Secretariat may deem an extra-ordinary review process to be necessary. the Prequalification Holder must provide all information requested of them. 

An extra-ordinary prequalification review will take place immediately if:

  • major changes have been made to the product
  • the Prequalification Holder has failed to notify WHO of complaints received about the product that may put vaccine potency at risk
  • UN agencies or product users have reported receipt of non-compliant products
  • complaint investigations have indicated significant quality or safety defects.

Additional sources of information during review

The following additional sources of information may be taken into consideration during product re-evaluation:

  • UNICEF Supply Division Quality Assurance Centre reports
  • results of structured field performance monitoring
  • performance feedback from governments and donor agencies
  • Prequalification Holders' change notifications
  • Prequalification Holders' product defect reports
  • questionnaires
  • anecdotal reports from the field
  • relevant policy decisions.