Kennedy won Senate confirmation to his job, in part, by promising not to change the nation’s vaccine schedule. Since taking office, he’s promised to “investigate” children’s shots, canceled meetings of expert vaccine advisers and directed officials to look again for connections between vaccines and autism, a link long-ago debunked.

Novavax is working with the FDA to meet additional requirements and hopes to secure full approval as soon as possible. However, the uncertainty surrounding the approval process highlights the ongoing challenges in navigating the pandemic and the vaccines that are crucial to ending it.