The TGA, like other regulatory agencies around the world, monitors the safety of medicines, including vaccines, to contribute to a better understanding of their possible adverse effects when they are used outside the controlled conditions of clinical trials. This is known as 'pharmacovigilance'.
Adverse event reports provide important information for the medicine safety monitoring program.
The TGA monitors the safety of medicines marketed in Australia using:
- reports of adverse events
- Risk Management Plans (RMPs) and Periodic Safety Update Reports (PSURs)
- reviews of literature
- sharing of information with other regulatory agencies
- sharing of information with Australian state and territory health authorities.
The TGA also works with the National Centre for Immunisation Research & Surveillance (NCIRS) on adverse events relating to immunisation.
Adverse event reports
Anyone can report an adverse event:
- reports by consumers and health professionals are voluntary
- sponsors are obliged to report any serious adverse events to medicines of which they are aware.
Adverse event reports made to the TGA are analysed regularly by scientific and medical experts.
The TGA provides medicine adverse event data to the World Health Organization database (VigiBase), and the TGA uses the data in VigiBase in its investigation of safety signals associated with medicines supplied in Australia.
Signal detection
Signal detection involves identifying patterns of adverse events associated with a particular medicine, or combination of medicines, that warrant further investigation.
A medicine safety signal may arise from:
- a previously unrecognised safety issue
- a change in the frequency or severity of a known safety issue, or
- identification of a new at risk group.
Steps following the identification of a potential safety concern
Once a safety signal has been detected it is assessed to determine the nature, magnitude and significance of the concern, and the impact on the overall benefit-risk profile of the medicine.
The information in adverse event reports is insufficient to calculate the incidence of any particular adverse event (that is, how often the adverse event has occurred in patients taking a particular medicine). Other information is necessary to assess the impact of reported adverse events on the benefit-risk profile of the medicine.
The TGA has to consider the balance between the benefits offered by any medicine and the potential risks associated with its use for the Australian population as a whole (or individual patient groups where the risks may be higher) before it makes a decision on the response to the signal. There are a range of actions that can follow when a potential safety issue is identified. These include:
- informing health professionals and consumers through alerts and articles in the Medicines Safety Update
- requiring changes to product labelling, such as adding warnings, precautions and adverse reaction information to the Product Information or Consumer Medicine Information
- withdrawing the market approval of the product, or narrowing the population in which it can be used
- recalling the medicine or particular batches of the medicine
- requiring the sponsor to undertake post-marketing studies to investigate the safety concern if more information is needed before a judgment can be made about the need for further action
- requiring no further action at this stage, but continuing to monitor the signal.
The Advisory Committee on Medicines (ACM)
The ACM provides independent medical and scientific advice on issues relating to the safety, quality and efficacy of medicines supplied in Australia including issues relating to pre-market and post-market functions for medicines.
The Advisory Committee on Vaccines (ACV)
The ACV provides independent medical and scientific advice on issues relating to the safety, quality and efficacy of vaccines supplied in Australia including issues relating to pre-market assessment, post-market monitoring and safe use in national immunisation programs.
Consultations with health professionals
The TGA cannot give medical advice to individuals and strongly encourages consumers to talk with a health professional if they think they might be experiencing an adverse event related to a medicine.
The benefits and the risks of a medicine to an individual need to be considered, along with the risks involved if no treatment occurs. The decision to use a particular medicine should be made between the patient and the patient's health professional, and should entail informed consent.