The U.S. Food and Drug Administration plans to add a warning about rare cases of heart inflammation in adolescents and young adults to fact sheets for the Pfizer/BioNTech (PFE.N), and Moderna (MRNA.O) Covid-19 vaccines. It is reported by Reuters.
U.S. Centers for Disease Control and Prevention (CDC) advisory groups found the inflammation in adolescents and young adults is likely linked to the vaccines, but that the benefits of the shots appeared to clearly outweigh the risk. Patients with heart inflammation following vaccination generally recover from the symptoms and do well.
Pfizer, whose vaccine has been authorized for use in Americans as young as 12, said in a statement that it is aware of the reports of myocarditis and pericarditis after mRNA vaccination. It said that the benefit risk profile of the Pfizer/BioNTech vaccine "remains positive".
Moderna is aware of reports of heart inflammation cases following administration of mRNA vaccines and is working with regulators.
Following the news, Moderna shares closed down 4.2%, while Pfizer fell 1.4%.
Health regulators in several countries have been investigating whether the Pfizer/BioNTech and Moderna shots using new mRNA technology present a risk and, if so, how serious.
Meanwhile, Ukraine holds talks with two American pharmaceutical companies on supplies of the vaccines against coronavirus.