Photo of the former North American headquarters of Novo Nordisk, Inc., in Plainsboro, N.J. taken on April 24, 2008. (AP)

In a statement released on Tuesday that sent the firm's shares leaping to a record high, Danish pharmaceutical giant Novo Nordisk claimed that the obesity medicine Wegovy reduces the risk of heart attacks and strokes by a fifth.

Even though it is preliminary, this is the first study to imply that this class of weight-loss drugs, which has garnered substantial public interest, can impart long-lasting improvements to cardiovascular health.

17,604 overweight or obese adults aged 45 participated in the research, and they were randomly assigned to receive either the injectable medication or a placebo over the course of five years.

Strokes, heart attacks, and cardiovascular deaths all decreased by 20%, according to a statement from Novo Nordisk, though the company did not provide a breakdown for each category.

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It added that it planned to file for regulatory approval to broaden the usage for Wegovy in the US and the EU in 2023. The trial's comprehensive results will be published at a scientific meeting later this year.

On Tuesday, Novo Nordisk's stock price increased by more than 17% at market closing in Copenhagen.

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

The results were also welcomed by the medical community.

Even though the trials "still need to be confirmed through careful peer review," they still show "the urgent need for patients living with obesity to be offered this effective and safe drug to prevent future disease," according to Simon Cork, senior lecturer in physiology at Anglia Ruskin University, who did not participate in the research.

According to Naveed Sattar, a professor of metabolic medicine, the University of Glasgow, the results "are exciting as preventing heart attacks and stroke with a drug that also lowers weight is very important for many patients." He also did not take part in the research but has previously consulted for Novo Nordisk.

Wegovy and the diabetes medication Ozempic are both produced by Novo Nordisk, the largest producer of insulin in the world. In May, the company reported a 39 percent increase in first-quarter earnings, helped by sales of its obesity therapies.

The European Medicines Agency, which has its headquarters in Amsterdam, announced in mid-July that it was examining data "on the risk of suicidal thoughts and thoughts of self-harm" with respect to three well-known weight-loss medications: Saxenda, Wegovy, and Ozempic. The last two both contain the active ingredient semaglutide.

Among more than a billion people worldwide suffering from obesity, according to the World Health Organization, there is intense competition among pharmaceutical companies to develop effective therapies.