Shares in Danish pharma group Novo Nordisk soared to a record high on Tuesday after a late-stage trial suggested its obesity drug Wegovy could reduce the risk of heart attacks or stroke by 20 percent.

Preliminary results showed that patients taking Wegovy had a 20 percent lower risk of suffering from a heart attack or stroke compared to those who took a placebo, Novo Nordisk said in a statement.

"We are very excited about the results," the company's executive vice president for development Martin Holst Lange said, adding the drug "has the potential to change how obesity is regarded and treated."

Novo Nordisk's share price closed up by more than 17 percent on the Copenhagen stock exchange on Tuesday.

The medical community also welcomed the results.

While the trials "still need to be confirmed through careful peer review, they demonstrate the urgent need for patients living with obesity to be offered this effective and safe drug to prevent future disease," said Simon Cork, senior lecturer in physiology at Anglia Ruskin University.

"This will not only provide significant financial savings for health bodies, but provide people with a greater quality of life," he said.

Novo Nordisk, the world's biggest insulin maker which manufactures both Wegovy and diabetes drug Ozempic, in May announced a 39 percent rise in its first quarter profit, buoyed by sales of its obesity treatments.

In mid-July, the Amsterdam-based European Medicines Agency said it was reviewing data "on the risk of suicidal thoughts and thoughts of self-harm" with three popular weight-loss drugs, Ozempic and Wegovy – which both have semaglutide as their main ingredient – and Saxenda, whose main ingredient is liraglutide.

The detailed results of the trial will be presented at a scientific conference later this year, Novo Nordisk said, adding that it plans to apply for regulatory approval to expand the uses for Wegovy in the US and the EU in 2023.

Competition among pharmaceutical groups over obesity treatments is fierce, with more than a billion people in the world suffering from obesity, according to the World Health Organisation. (AFP)