Novavax (NVAX) shares plummeted 11.57% in pre-market trading on Monday, as vaccine makers faced a selloff following reports of a top FDA vaccine official's impending resignation.

According to the Wall Street Journal and other media outlets, Peter Marks, a key figure in the U.S. Food and Drug Administration's vaccine division, is set to leave the agency. Marks, who played a crucial role in developing COVID-19 vaccines during former President Donald Trump's first term, has reportedly been given the choice to resign or be fired, with his resignation effective April 5.

The news has sent shockwaves through the vaccine industry, with several major players seeing significant declines. Moderna fell 13.7%, while Pfizer and BioNTech dropped 1.6% and 5.5% respectively. The sector has been under pressure since Trump's re-election and his appointment of well-known vaccine skeptic Robert F. Kennedy Jr. to lead the Department of Health and Human Services, the country's top health agency. This latest development has further intensified concerns about the future of vaccine development and regulation in the United States.