Web-based surveys are a feasible way of rapidly collecting drug safety data on novel vaccines when they are rolled out quickly over a large area, according to a new European study involving the UK’s leading drug safety unit.

The study, conducted in seven European countries, aimed to prospectively monitor the safety of the COVID-19 vaccines as they were rolled out at scale.

Participants completed questionnaires for at least six months following the first dose of COVID-19 vaccine. Data on potential adverse reactions to the vaccine was captured, pooled and crucially, made available in near-real time to researchers. This allowed current rates of adverse reactions to be regularly updated as the vaccines were introduced across Europe and in turn provided valuable safety data for healthcare professionals, regulatory authorities, and the general public.

The study's authors believe that this approach to safety monitoring could be used for future vaccine rollouts, providing rapid safety data to support expedited public health decision-making.

The Drug Safety Research Unit was invited to lead the UK arm of the study.

Professor Saad Shakir, Director of the Drug Safety Research Unit, said: “When the first COVID-19 vaccines became available a large scale roll out was needed to ensure people received this vital medication. To ensure this was done safely, the introduction of a monitoring system in multiple countries for rapid data collection, was desperately needed.

“We have shown that online reporting is a feasible way of collecting data from people in real life conditions. These patient reported outcomes are important because they include information on adverse reactions that would not be found in medical records as patients who experience short-term, non-serious reactions would not typically consult a healthcare professional. This approach is well suited to monitoring safety of vaccines at the start of roll-out when large databases suitable for retrospective safety studies are not yet available.”

In the study, published in Drug Safety, 117,791 participants from seven European countries were recruited.

The majority of the respondents received the AstraZeneca vaccine (75.9%), followed by BioNTech/Pfizer (12.4%), Moderna (9.6%), and Janssen (2.1%).

Fatigue, headache and injection-site pain were the most commonly reported adverse reactions.

Rates of adverse events of special interest (AESIs) were 0.1–0.2% across all vaccine brands and serious reactions or AESIs were uncommon, consistent with those reported on product labels.

The study, led by Monika Raethke of Lareb, the Netherlands Pharmacovigilance Centre, had limitations, which include relying on individuals to complete questionnaires and that participants who experienced an adverse rection would be more likely to continue their participation longer than those who experienced no adverse reaction. They also recognise that due to the different speed with which vaccines were deployed in different countries, data collection where vaccines had been rolled out before the study started led to certain populations that were vaccinated early on in the process, not being included.

The collaboration received funding from several sources, including the European Medicines Agency (EMA), with data collection in some countries funded by the country’s government.

Final results and analysis from the study, including data from subsequent vaccine doses, will be published in due course.