French health authorities have advised against the use of Moderna’s Spikevax COVID-19 vaccine for people under the age of 30 after a large study published on Monday showed the shot carries a slightly higher risk for heart-related diseases after the second dose.
The results from the study that was led by Epi-Phare, an independent group of scientists who act as advisors to the French government, showed that vaccines from both Pfizer and Moderna were associated with an increased risk of hospitalization for myocarditis (inflammation of the heart muscle), and pericarditis (inflammation of the tissue surrounding the heart), within seven days of vaccination.
“This study confirms the existence of a risk of myocarditis and pericarditis within 7 days following vaccination against COVID-19 with an mRNA vaccine (Pfizer BioNTech and Moderna) in people aged 12 to 50 years, particularly young people under 30 years old,” it concluded.
The agency noted that the risk is higher with Moderna, although the “number of cases attributable to vaccines appears infrequent in relation to the number of doses administered.”
According to an opinion published by Haute Autorite de Sante (HAS), the risk was around five times lower with the Pfizer vaccine compared to the jab offered by Moderna for people in this age group.
HAS, which does not have the legal authority to ban or license drugs in the country but acts as an advisor to health officials, did recommend Moderna over Pfizer for people over the age of 30, saying its effectiveness is slightly superior.
The study looked at all hospitalizations of myocarditis or pericarditis that occurred in France between May 15 and Aug. 31 among people aged between 12 and 50. No deaths among patients hospitalized with these illnesses following vaccination have been reported.
France’s advice against the Moderna vaccine comes after regulators in several other countries, including Canada, Finland, Norway, and Sweden, have also taken a more defensive stance on Spikevax over heart-related safety concerns affecting younger people. Denmark halted its distribution of the vaccine to anyone under the age of 18.
The European Union’s drug regulator EMA last month approved Moderna’s booster vaccine for all age groups over 18, at least six months after the second dose.
Earlier this year, the EMA also said that it had found a possible link between the rare inflammatory heart condition and COVID-19 vaccines from both Pfizer’s and Moderna’s vaccines.
Reuters contributed to this report.