Moderna Stock Slips as FDA Delays RSV Vaccine Approval

Moderna (MRNA) shares lost ground in intraday trading Friday as the biotech’s effort to move beyond just a COVID-19 vaccine was stalled somewhat by U.S. regulators looking at its new shot to treat respiratory syncytial virus (RSV).

Moderna reported that the Food and Drug Administration (FDA) has advised the company that it does not expect to complete its review of the vaccine, known as mRNA-1345, until the end of the month. Previously, it was expected officials would approve it on May 12. 

The company noted that the FDA did not inform it of “any issues related to vaccine safety, efficacy or quality that would prevent the approval.”

Moderna added that despite the delay, it still anticipates mRNA-1345 to be reviewed at the Centers for Disease Control and Prevention’s (CDC) Advisory Committee on Immunization Practices meeting June 26-27. The company pointed out that the review was necessary prior to commercial launch of the treatment.

With the end of the pandemic, Moderna has moved to use its mRNA technology to create vaccines for other diseases. Along with RSV, the company has been working on developing a combination shot that works for both COVID-19 and the flu, and a cancer-fighting treatment to be used along with Merck’s (MRK) blockbuster drug Keytruda. 

Moderna shares fell 3% to $118.93 as of noon ET Friday but are up about 20% in 2024.