U.S. FDA gives emergency use authorization to Novavax's COVID-19 vaccine

Study: Old antibodies no longer effective Study co-lead Igor Stagljar discusses says older antibodies either from vaccination or prior infection are not effective against Omicron.

The U.S. Food and Drug Administration on Wednesday authorized Novavax's COVID-19 vaccine for emergency use in adults. It is the fourth coronavirus vaccine available in the United States, and it uses a different type of vaccine technology than the shots already available.

Novavax's vaccine will be available as two-dose primary series for people 18 and older. The FDA's independent Vaccines and Related Biological Products Advisory Committee voted in favor of authorization of the vaccine June 7, saying that the benefits of the vaccine outweigh its risks for adults.

It is a protein-based vaccine, and such vaccines use harmless protein fragments of the virus to teach the immune system how to spot the virus and fight it off. The vaccine was created out of a genetic sequence of the first strain of the coronavirus.

Late-stage trials found that the efficacy of the vaccine against mild, moderate and severe disease is 90.4%, according to the company. There is not sufficient evidence to evaluate the impact of the vaccine on transmission of the virus.

Novavax also announced in early July that its vaccine shows "broad" immune response to currently circulating variants, including Omicron subvariants BA.4/5.

The shots can't be administered until the US Centers for Disease Control and Prevention's independent vaccine advisers weigh in on whether to recommend the vaccine and the CDC director has signed off on the recommendation. The CDC's Advisory Committee on Immunization Practices is scheduled to meet on July 19.

On Monday, the Biden administration announced that it had secured 3.2 million doses of the Novavax vaccine.