Los Angeles, July 21 : The US Centers for Disease Control and Prevention (CDC) has endorsed recommendation that Novavax's Covid-19 vaccine be used as another primary series option for adults ages 18 years and older. The recommendation came on Tuesday following a meeting of the CDC Advisory Committee on Immunization Practices, Xinhua news agency reported. The Novavax vaccine will be available as two-dose primary series for adults, three weeks apart. It is the fourth Covid-19 vaccine available in the US, and it uses a different type of vaccine technology than the other three approved vaccines. "Novavax's Covid-19 vaccine, which will be available in the coming weeks, is an important tool in the pandemic and provides a more familiar type of Covid-19 vaccine technology for adults," said the CDC in a statement. Last week, the US Food and Drug Administration issued an emergency use authorisation for the Novavax Covid-19 vaccine in individuals 18 years of age and older. /IANS