An initial analysis by the EMA found the AstraZeneca jab safe after several countries suspended its use. The agency also said it could not "definitively" rule out a link between the shot and blood clots.
The European Medicines Agency (EMA) on Thursday declared the AstraZeneca COVID-19 vaccine safe for use after it was suspended by 13 EU member states.
The EMA held a special meeting to look into the connection between unusual blood clot disorders discovered in several cases after people had received the AstraZeneca vaccine.
Germany, France, Spain and others temporarily halted vaccinations with the British-Swedish shot after EU member states reported 30 cases of blood clot disorders, including a rare and difficult-to-treat condition called cerebral venous thrombosis (CVT).
Some 5 million people have so far been administered the AstraZeneca COVID-19 vaccine in the EU.
Emer Cooke, the executive director of the EMA, said the AstraZeneca vaccine is a "safe and effective option to protect citizens from COVID-19." The EMA said the benefits of the vaccine far outweigh the risks after coming to a "clear scientific conclusion."
At the same time, Cooke said the EMA could not "definitively rule out a link" between the vaccine and blood clots.
The EMA will conduct additional scientific studies into the matter and recommended that leaflets about the vaccine include information about blood clot risks to raise public awareness.
Following the initial assessment, several other European countries said they would soon re-start vaccinations with AstraZeneca doses.
Germany plans to restart its vaccinations on Friday, Health Minister Jens Spahn said.
Italy and France will also resume administering the vaccine starting on Friday, both countries' prime ministers announced. Their plans mirror those of Latvia, Lithuania and Bulgaria.
Sweden said it would make a decision next week on whether to resume administering the vaccine.
British Prime Minister Boris Johnson and French Prime Minister Jean Castex both said that they will be given the AstraZeneca vaccine on Friday.
The EMA meeting comes after Britain's health regulators said they found no direct link between the AstraZeneca shot and blood clots. The UK has continued to use the AstraZeneca jab, administering over 11 million doses to the British population.
"The available evidence does not suggest that blood clots in veins (venus thromboembolism) are caused by COVID-19 vaccine AstraZeneca," the Medicines and Healthcare products Regulatory Agency (MHRA) said on Thursday.
AstraZeneca's chief medical officer, Ann Taylor, welcomed the positive assessments by EU and UK regulators.
"Vaccine safety is paramount and we welcome the regulators' decisions which affirm the overwhelming benefit of our vaccine in stopping the pandemic," Taylor said in a statement.
The German Health Ministry described its suspension of the vaccine on Monday as a "precaution" on the basis of advice from the state health regulator, the Paul Ehrlich Institute (PEI).
Seven people aged between 20 and 50 were diagnosed with CVT up to 16 days after vaccination, the PEI reported on Monday. They would have expected just one case among the 1.6 million who have been given the jab.
Earlier this week, the EMA said there was no connection between the shot and the blood clots reported in some vaccine recipients. The EMA also at the time stressed the importance of building trust in the safety of the vaccines.
On Wednesday, the World Health Organization (WHO) said that it was also carrying out an investigation into the blood clots in AstraZeneca vaccine recipients but recommended that countries continue to administer jabs as they deemed the benefits to outweigh the costs.
The AstraZeneca vaccine is one of the cheaper options on the market. The WHO vaccine sharing initiative COVAX has relied heavily on the jab — which is being produced not-for-profit during the pandemic.
Unlike the BioNTech-Pfizer or Moderna vaccines, the AstraZeneca shot does not need to be kept at ultra-low temperatures, making it easier to store in less developed countries or less accessible areas.
Some 25 African countries have already been given doses of the AstraZeneca vaccine through the COVAX program. However, some of them have now joined the growing list of countries to suspend its use.
Experts have warned that this may hamper the battle against the virus in countries where people are already skeptical of the virus or of vaccines in general.