Europe's drug regulator has reiterated that the benefits of AstraZeneca's Covid-19 vaccine outweigh any risks, as part of a detailed guidance from ongoing reviews into rare blood clots to help individual nations determine the shot's use.
The renewed backing comes after several countries in the European Union and worldwide have limited the use of the vaccine, known as Vaxzevria, while Denmark has stopped its use altogether, after possible links to clotting issues were confirmed.
The interim analysis by a committee of the European Medicines Agency (EMA) determined that serious side effects of rare blood clots are likely to occur in 1 out of 100,000 vaccinated people, the regulator said in a statement.
EMA officials said in a briefing that today's update was aimed at putting into context the data it has collected and analysed to help 27 EU member states work out how to use the shot based on their local situations.
The advantages of getting the vaccine increase with age and with any rise in infections rates, but the benefits were for now evident across all scenarios and ages, the officials said.
They said the recommendation may be subject to change because more data is being collected, and for instance not all EU member states had included the sex of the vaccine recipients in their data.
But Peter Arlett, head of EMA's data analytics and methods task force, said: "The benefit risk balance of the AstraZeneca vaccine is positive. It's preventing serious disease and saving lives."
Earlier this month, the EMA said it had found a possible link between AstraZeneca's coronavirus vaccine and a similar, rare blood clotting problem connected to the one from Johnson & Johnson which led to a small number of deaths.
There was not enough data on Vaxzevria from Europe to determine if blood clot risks with low blood platelets would differ with each dose of the vaccine, or to provide context on its benefits and risks with regards to sex, the EMA said.
Countries are also in the midst of determining whether to use J&J's vaccine over concerns of blood clots.
Regulators have found these events occurred mostly in the brain and abdomen.
We need your consent to load this rte-player contentWe use rte-player to manage extra content that can set cookies on your device and collect data about your activity. Please review their details and accept them to load the content.Manage Preferences
The EMA's report on the AstraZeneca vaccine said this may guide EU member states when they adjust their vaccination strategies, depending on the infection rates and the age groups of people who still need to receive a vaccine.
The new detailed analysis will provide plenty of food for thought for NIAC who this weekend will be finalising their advice about using the very similar Johnson & Johnson vaccine.
It shows that people in their 40s have the greatest risk of experiencing the rare blood clotting events at 2.1 cases for every 100,000 people in that age group vaccinated.
Next riskiest are those in their 20s followed by the 30-somethings.
The analysis also shows the risk-benefit trade-off for each age group.
For instance, for every 100,000 people in their 50s who receive the AstraZeneca vaccine there are likely to be 1.1 cases of the rare blood clots compared to the savings of up to 208 hospitalisations, 28 ICU admissions, and 14 deaths in that age group.
For those in their 60s, the trade-off is one rare blood clot for every 100,000 people vaccinated, compared to the saving of up to 324 hospitalisations, 50 admissions to ICU, and 45 deaths.
Additional reporting George Lee