PERTH, Australia – With the first COVID-19 vaccine ready to be launched in Australia, the Therapeutic Goods Administration (TGA) has released guidance on its pharmacovigilance plan to track real-world safety data and adverse events following immunization.

To date, the TGA has approved two COVID-19 vaccines – Astrazeneca Pty Ltd.’s recombinant adenovirus vaccine and Pfizer Australia Pty Ltd.’s COVID-19 mRNA vaccine, branded Comirnaty.

The Pfizer vaccine will begin to be administered on Feb. 22, and the Astrazeneca vaccine will be rolled out in March. First groups will be frontline workers and the elderly who are in nursing care facilities.

Although clinical studies provide extensive information about the safety of the vaccines, they may not detect very rare adverse events that can only be identified when a product is used in very large numbers of patients, the TGA said.

Similarly, clinical trials may not fully characterize the safety profile of a product in certain population groups, such as the elderly, pregnant women, or people with other medical conditions, because these people may not have been included in the trials.

The rapid development of COVID-19 vaccines has meant that the typical regulatory approval and production processes are being expedited. Most sponsors of COVID-19 vaccines will apply for registration using the TGA’s provisional approval pathway, which allows for temporary registration of new therapies where the need for early access outweighs the risks.

Information from ongoing clinical trials and safety studies will continue to be collected and analyzed after provisional approval. The TGA has requested that vaccine sponsors submit additional safety monitoring reports and monthly safety summaries. The agency will prioritize its staffing levels to ensure that resources are available to analyze safety study reports.

The TGA, along with other international regulators, and vaccine sponsors will continuously review safety and effectiveness information collected from use in mass vaccination programs worldwide.

Safety at the fore

As part of its vaccine safety plan, the TGA will be publishing a weekly safety alert that will include information about reported suspected side effects as well as other safety alerts.

The aim of the TGA’s vaccine safety monitoring plan is to strengthen the existing vaccine vigilance system to allow for early detection and investigation of suspected adverse events. The key objectives of the COVID-19 vaccine safety monitoring plan are:

  • timely collection and management of reports of COVID-19 vaccine adverse events following immunization;
  • timely detection and investigation of COVID-19 vaccine safety signals;
  • timely action to address any COVID-19 vaccine safety concerns;
  • timely communications to inform the public of emerging COVID-19 vaccine safety information and to support public confidence in vaccines; and
  • close collaboration and coordination with other vaccine safety stakeholder groups.

Every adverse event following immunization is valuable and contributes to safety monitoring, the TGA said. To that end, the agency is ensuring that its adverse event reporting forms capture information that is specific to COVID-19 vaccines and that reports are shared between the TGA and states and territories in a timely manner.

Signal detection involves identifying patterns of adverse events that may identify a new at-risk group. When such a safety signal is identified, the agency will conduct a thorough investigation to determine what action is needed.

Part of the work for the agency involves understanding COVID-19 safety profiles, such as background adverse event rates for the vaccines that are informed by premarket evaluations of safety data and the risks associated with the new types of vaccines.

By accessing the Australian Immunization Register and vaccine distribution data, the TGA will be able to calculate COVID-19 immunization rates to help it quickly analyze adverse event rates to detect, confirm or disprove emerging safety signals.

For example, background rates of certain health events such as heart problems in the general population will be calculated for comparison against COVID-19 vaccine adverse events.

The agency will collaborate with Ausvaxsafety to receive active surveillance information and coordinate safety signal detection activities. Ausvaxsafety will be using SMS messaging to survey people who receive the vaccine as part of their active surveillance activities.

The TGA aims to improve mechanisms for sharing information on COVID-19 safety signals between international regulators. It currently co-chairs a group that facilitates the sharing of COVID-19 vaccine-specific safety information through the International Coalition of Medicines Regulatory Authorities.

A standing COVID-19 expert advisory committee is being established to provide advice on COVID-19 vaccine safety issues, and the TGA will draw on members of the Advisory Committee on Vaccines and the Australian Technical Advisory Group on Immunization.