Vaccine safety: MHRA releases surveillance strategy

The rapid detection, characterisation and quantification of safety issues related to Covid-19 vaccines is essential to protecting public safety and ensuring public confidence. 

In view of this, the Medicines and Healthcare products Regulatory Agency (MHRA) released its four-pronged strategy to vaccine safety surveillance on 5 February 2021. The strategy was informed by an Expert Working Group established by the Commission on Human Medicines.

The four prongs of the strategy are as follows:

1. Enhanced passive surveillance - 'observed vs expected analysis': the MHRA will perform enhanced statistical analysis on data generated through the existing Yellow Card scheme (which allows members of the public and healthcare professionals to voluntarily report suspected side effects to the MHRA). A specific Covid-19 interface has been added to the Yellow Card scheme to also allow for more targeted reporting. The MHRA will use various statistical methods to evaluate 'observed' versus 'expected' event reports, to determine whether more events are occurring after vaccination than might be expected ordinarily. This will assist the MHRA in identifying when and where vaccine-related side effects are signalled. 
2.  Rapid Cycle Analysis and Ecological Analysis: to supplement the Yellow Card scheme (which relies on direct reporting), the MHRA will also analyse anonymised electronic healthcare records, particularly by way of the CPRD Aurum dataset, which captures data from 13 million registered GP patients in the UK. The MHRA will perform Rapid Cycle Analysis on this data to track a range of theoretical side effects, in order to detect safety signals. The MHRA will also perform ecological analysis to monitor trends in high priority vaccination population cohorts (e.g. increased trends among the elderly).
3. Targeted active monitoring - Yellow Card Vaccine Monitor: the MHRA has developed a new, voluntary, follow-up platform for a randomly selected group of those vaccinated through the NHS (several thousand in number). This group will be contacted at set intervals to determine the frequency and severity of any vaccine side effects.    
4.  Formal epidemiological studies: The above methods detect signals and patterns, but do not necessarily confirm vaccine causation. As such, where necessary, formal epidemiological studies will be undertaken to solidify causal links identified through other vigilance activities. 

To augment the four-pronged strategy, the MHRA has generally committed to continue to work with Public Health England, vaccine manufacturers and academics. If serious issues are identified by the MHRA, by whatever means, the MHRA states that it will take regulatory action if necessary. In addition, the MHRA will "operate a transparent process" and will produce up to date safety data on its website.