(Reuters) - Shares of Novavax (NASDAQ:NVAX) Inc surged nearly 20% on Wednesday after advisers to the Food and Drug Administration overwhelmingly backed the use of its COVID-19 vaccine, bringing the shot a step closer to a U.S. launch.
The stock tumbled about 20% on Friday after the heath regulator's reviewers flagged concerns of a type of heart inflammation following the vaccination, adding uncertainty over the outcome of Tuesday's meeting.
However, the voting by the outside advisers - 21 for, none against and 1 abstention - indicates that the FDA could soon authorize the fourth vaccine in the United States, where Novavax hopes it would become the shot of choice among vaccine skeptics.
The positive vote "acknowledges the strength of our data and the importance of a protein-based Covid-19 vaccine", Novavax Chief Executive Officer Stanley Erck said on Tuesday.
The FDA panel voting is a positive development for Novavax, analysts said, as it reduces uncertainty around a vaccine that has had a long path to authorization.
Jefferies analyst Roger Song said the cases of a type of heart inflammation, though concerning, would result in a warning very similar to that of rival mRNA vaccines from Moderna (NASDAQ:MRNA) Inc and Pfizer (NYSE:PFE).
The vote marks a "challenge to the dominance of mRNA vaccines in the COVID-19 market," said SVB Securities analyst Mani Foroohar in a note.
If the FDA authorizes the vaccine, the U.S. Centers for Disease Control and Prevention will need to endorse it before becoming available in the country.
Novavax's shares were up 19% at $56.59 before the bell.