The US drug regulator on Thursday denied market authorization to a number of vaping products after finding they failed to show that smoking cessation benefits to adults outweigh risks posed to youth.

The products included flavors, such as "Apple Crumble," "Dr Cola" and "Cinnamon Toast Cereal" by companies JD Nova Group, Great American Vapes, and Vapor Salon.

It comes as the Food and Drug Administration (FDA) is nearing a court-ordered September 9 deadline for submission of applications to remain on the market under new stricter rules that are reshaping the industry.

"Congress gave the FDA the authority to regulate tobacco products to protect the public from the harmful effects of tobacco use through science-based regulation," said Acting FDA Commissioner Janet Woodcock.

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"We know that flavored tobacco products are very appealing to young people, therefore assessing the impact of potential or actual youth use is a critical factor in our decision-making about which products may be marketed."

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The products denied authorization may not be delivered to the market, or have to be removed if they have already reached shelves.

In all, the FDA has received applications from over 500 companies.

No decisions have so far been announced about the companies with the leading market share, Juul Labs and Reynolds American which makes Vuse e-cigarettes.

E-cigarettes entered the US market in 2007 and have been the most commonly used tobacco product among American youths since 2014.

To curb youth vaping, the FDA last year barred flavors from smaller e-cigarettes that use pods, such as those made by market leader Juul.

Tank-based rechargeable vaping devices, primarily sold in vape shops, were left exempt.

US lawmakers also raised the federal minimum age for tobacco and e-cigarette sales from 18 to 21 in December 2019.

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About 3.6 million young people in the US were current (in the past 30 days) e-cigarette users in 2020, down from 5.4 million in 2019, according to the National Youth Tobacco Survey.

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