Moderna, Pfizer Stocks Fall After CDC Panel Flags Heart Inflammation Risk In Young Adults Receiving COVID-19 Vaccine

Shares of COVID-19 vaccine companies Moderna Inc MRNA, Pfizer Inc. PFE and BioNTech SE - ADR BNTX are moving sharply lower Wednesday.

What Happened: Administering of mRNA vaccines, the class of vaccines developed by Moderna and Pfizer-BioNTech, resulted in higher observed vs. expected myocarditis/pericarditis cases in 16 to 24 years olds following dose two of mRNA vaccines, CDC's COVID-19 Vaccine Safety Technical Work Group said in a report.

The report was prepared for discussion by CDC's Advisory Committee on Immunization Practices, which is being held Wednesday to look into a possible link between mRNA vaccines and a heart condition.

Since April, there have been increased reports of cases of inflammation of the heart — myocarditis and pericarditis — after being administered either Pfizer-BioNTech or Moderna's mRNA vaccines, the panel said in the report.

The report also said CDC and its partners are actively monitoring reports, by reviewing data and medical records, to see if there is any relationship to the vaccination.

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The panel also issued recommendations for clinicians that include reporting of all cases of myocarditis and pericarditis to the Vaccine Adverse Event Reporting System, being in the know of symptoms in young adults, initial evaluation and follow-up.

CDC also puts the rate per million cases at 12.6 following dose two of mRNA vaccines, with Pfizer's numbers at 8 per million cases and Moderna's at 19.8 per million cases.

Why It's Important: Both Pfizer-BioNTech and Moderna recently received authorizations for use of their vaccines in adolescents.

When initial reports of heart inflammation came about, the companies denied any link between their vaccine and the condition. The CDC report also observed that the affected individuals generally recovered from the symptoms and are doing well.

COVID-19 vaccine revenues have provided a shot in the arm of these companies, augmenting their topline substantially.

At last check, Moderna shares were down 5.24% at $209.76, Pfizer was down 1.10% at $39.17 and BioNTech shares dropped 3.10% to $229.17.

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