Novo Nordisk's U.S. shares plummeted Tuesday after the company said it sees sales and profit growth declining this year, hit by lower prices in the U.S. and loss of exclusivity for its blockbuster Wegovy and Ozempic in China, Brazil and Canada.

Novo's American depositary shares fell as much as 14% in afternoon trading, after a trading halt. The results were published after the closing bell in Copenhagen, where the company has its primary listing, and ahead of the scheduled release early Wednesday.

For 2026, the drugmaker sees sales and operating profit both declining between 5% and 13% at constant exchange rates, far worse than analysts had expected.

It comes as the Danish drugmaker is fighting to regain its footing in the weight-loss space amid fierce competition.

"In 2026, Novo Nordisk will face pricing headwinds in an increasingly competitive market," CEO Mike Doustdar. "However, we are very encouraged by the promising early uptake from the US launch of Wegovy pill, and we remain confident in our ability to drive volume growth over the coming years."

The outlook reflects expectations for a sales decline in the U.S., its biggest market, but sales growth ex-U.S. Novo said. "In 2026, the global GLP-1 market expansion is assumed to continue, enabling Novo Nordisk to increase patient reach and expand volumes," the company said in a statement.

In 2025, sales increased by 10% and operating profit increased by 6%, in line with the company's latest guidance, which it lowered throughout 2025, citing challenges in the U.S. market.

Novo also said that it will roll out Wegovy in more markets in 2026 and expects to introduce the higher 7.2 mg dose in a number of countries.

The Ozempic maker is banking on its Wegovy pill and next-generation weight-loss injectable CagriSema to recapture market share in the U.S. – and revive its slumping stock price. 

Novo stock fell 46.5% last year, driven by a series of guidance cuts, leadership shakeups and intensifying competition, but has regained some ground after becoming the first company to launch an oral GLP-1 treatment for obesity in the U.S. market.

Novo launched the oral version of the blockbuster weight-loss medicine Wegovy in the U.S. early January, and, despite its promising start, the market is closely watching how Novo Nordisk will fare along with U.S. rival Eli Lilly, which is expected to launch its own weight loss pill in the first half of 2026.

"Investors want to see they are making the most of this lead, particularly in the direct to patient (mostly self-pay or cash pay) channel, closing some of the large gap that widened between them and Lilly in this channel in 2025," said Morningstar analyst Karen Andersen.

Semaglutide, the active ingredient in Wegovy and Ozempic, is losing exclusivity in markets like Canada, Brazil and China in 2026. Together with significant pricing pressure in its largest market, the U.S., analysts had forecast sales growth to moderate this year to single digits after several years of much higher growth.

Coming into the print, Barclays analyst James Gordon said the Novo guide was expected to crystalize further downgrades, however could also act as a clearing event given the "significant investor concern" about this year's outlook.

"[Guidance] cuts could be at least partly mitigated by investors taking the opportunity to then buy into the Oral Wegovy US launch and Injectable Wegovy potential US volume inflection this year."

Novo has faced pressure for the past 18 months as rival U.S.-based Eli Lilly's rival weight-loss drug tirzepatide – sold as Mounjaro and Zepbound – resulted in more pronounced weight loss than Novo's medicine, and surpassed Novo in U.S. market share.

Novo and Lilly in November announced a deal with the Trump administration to cut prices for their best-selling drugs, which are expected to increase volumes but ultimately hurt total sales.

The agreements involved cutting prices of their GLP-1 drugs for Medicare and Medicaid in 2026 as well as offering them directly to consumers at a discount through the forthcoming TrumpRx.gov website, expected to launch in January.

In the fourth quarter, Novo net sales amounted to 79.1 billion Danish kroner ($12.5 billion), slightly ahead of analysts' expectations of 77.8 billion kroner, according to LSEG estimates. Operating profit in the quarter was largely in line with estimates at 31.7 billlion kroner, down 14% year-on-year.

Ozempic, its best-selling medicine, brought in 31.8 billion in the quarter, up 1% from the same period last year at constant exchange rates. Wegovy sales were 21.9 billion kroner, up 17%.

- CNBC's Annika Kim Constantino contributed to this report