European medical experts recommend a third BioNTech/Pfizer or Moderna Covid-19 booster shot for people with a weak immune system, the European Medicines Agency (EMA) announced on Monday.
The announcement came after the agency’s human medicines committee evaluated several studies.
The studies showed that a third dose of these vaccines boosted the ability of organ transplant recipients to produce antibodies against the coronavirus.
According to the EMA, the booster shot should come at least 28 days after the second vaccination.
For those aged 18 years and above with a normally functioning immune system, a booster shot could be considered at least six months later, EMA said, drawing on findings from BioNTech’s vaccine which showed an increase in antibodies for 18 to 55-year-olds.
Comparable studies with Moderna’s vaccine were still under review.
The risk of inflammatory heart disease or other very rare side effects following booster vaccinations were not yet known, EMA said, adding that this was being closely monitored.
As with all medicines, the EMA said it was continuing to monitor the safety and efficacy of the vaccines. The agency also pointed out that the decision on whether to offer additional vaccine doses was up to individual EU member states.