April 23 - Europe's drug regulator reiterated on Friday the benefits of AstraZeneca's COVID-19 vaccine outweigh any risks, delivering an assessment based on continuing reviews into rare blood clots to help countries 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. Denmark has stopped its use altogether, after possible links to clotting issues in combination with low platelet levels 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 the update on Friday 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 gender, the EMA said.

Countries are also in the midst of determining whether to use J&J's vaccine over concerns about blood clots and U.S. regulators were meeting on Friday to consider whether it is safe to resume J&J injections.

Regulators have found these events occurred mostly in the brain and abdomen.

(Reporting by Pushkala Aripaka in Bengaluru, Ludwig Burger in Frankfurt, Alistair Smout and Keith Weir in London; Writing by Josephine Mason; Editing by Saumyadeb Chakrabarty and Sriraj Kalluvila, William Maclean)