Post-licensure vaccine safety

Key point

Spontaneous reporting is the cornerstone of most post-licensure safety monitoring systems because of its relative ease of implementation and ability to capture unexpected events.

Post-licensure surveillancePost-licensure surveillance (also known as post-marketing surveillance)Pharmacovigilance conducted after a product has been licensed and introduced for use in a population. of vaccine safety is critical. The conditions and reasons for safety monitoring change following licensureLicensureThe granting of a license to conduct a regulated procedure, for example, to conduct a trial of a new vaccine or to approve a vaccine for routine delivery to the public in a vaccination programme. and introduction of a new vaccine:

Passive surveillance systems

Passive surveillance systems
  • Spontaneous reporting system is the corner stone of vaccine pharmacovigilance system because of its relative ease of implementation, its cost and ability to monitor all vaccines and capture all events.

    These reporting systems monitor events reported by health care providers and consumers and do not actively seek out and collect data or measure outcomes using study protocols.

Active surveillance systems

Post-licensure clinical trials and phase IV surveillance studies
Large linked databases (LLDBs)
Clinical centers, including the Clinical Immunization Safety Assessment (CISA) centers
  • Tertiary clinical centers have been used to conduct research on immunization-associated health risks.
  • More recently, WHO piloted the establishment of a global network of hospital-based sentinel sites in LMICs across the WHO regions for vaccine safety signal verification and hypothesis testing the Global Vaccine Safety Multi Country collaboration project.81
  • The USA's Clinical Immunization Safety Assessment (CISA) Network is a national network of six medical research centers with expertise in immunization safety conducting clinical research on immunization-associated health risks. Established in 2001 as a collaborative project between the CDC, six medical research centers and American Health Insurance Plans, CISA conducts clinical research on vaccine adverse events and the role of individual variation.21