By Kamal Choudhury (Reuters) -Novavax shares jumped more than 15% on Monday after the company secured a long-awaited U.S. regulatory approval for its COVID-19 vaccine, albeit with new conditions, which helped allay some investor concerns over the future of the shot.

Novavax’s shot is the only protein-based COVID vaccine available in the U.S. Until now, it had only been allowed for emergency use in people 12 and up. Unlike the mRNA vaccines from Pfizer and Moderna,

Late-stage trial data suggest that a new COVID-flu vaccine offers good protection against both infections, but experts expect the shot's approval may be delayed.