A new obesity drug, Wegovy, slashed the risk of serious heart problems by 20 percent in a large trial, the drug’s maker said on Tuesday, a finding that could challenge the perception of weight loss drugs as nothing more than cosmetic medicines and put pressure on insurers to cover them.
The trial was the first to demonstrate that the new class of obesity drugs could bring lasting benefits to heart health for people who were overweight but did not have diabetes.
With obesity affecting 100 million adults in the United States and accounting for nearly $150 billion in annual health care spending, the new treatments could help address some of the most significant and costly afflictions in American medicine.
The results “demonstrate the urgent need for patients living with obesity to be offered this effective and safe drug to prevent future disease,” said Simon Cork, an obesity expert at Anglia Ruskin University in England who has no ties to the drug.
Many details were missing from the announcement on Tuesday by Wegovy’s maker, Novo Nordisk. The company said that the drug reduced the overall risk of heart attacks, strokes and cardiovascular deaths by 20 percent. But it did not break out the effects of the drug on each of those outcomes individually.
The company also did not describe how much weight patients lost or provide details on side effects of the drug and how many patients decided to stop taking it. The data has not yet been published in a peer-reviewed journal; the company said it would present more detailed results at a scientific conference later this year.
Still, the trial included nearly 18,000 adults with previous cardiovascular disease and tracked them for up to five years. It bolstered the idea that obesity drugs can deliver long-term health benefits in addition to helping patients lose weight, experts said, undermining the argument that they are merely vanity drugs with little bearing on patients’ underlying health.
That could prompt more insurers to pay for the drug, at least for patients who, like the trial participants, already had evidence of heart disease.
“It’s going to make it much harder to deny coverage and not pay for these products for a non-diabetic population,” said Craig Garthwaite, a health economist at Northwestern University’s Kellogg School of Management. “It’s going to make it very difficult to make the argument that this isn’t part of an essential health benefit when there are cardiovascular benefits.”
Medicare does not cover weight loss medications and some employer insurance plans have refused to pay for them, owing to the view that the drugs are not essential medical remedies. The drug’s high list price of $1,349 a month puts it out of reach for most whose insurance will not cover it.
Reducing the risk of heart attacks or strokes could not only spare many Americans years of suffering and medical complications but also bring other economic benefits, restoring productivity losses from heart disease and reducing spending on less effective obesity treatments, Dr. Garthwaite said.
Even so, he said, the benefits for patients’ heart health are far enough down the road that insurers themselves may not see direct cost savings. If other drugs from the new class of obesity treatment also prove able to reduce cardiovascular disease, he said, that could create competition between products that eventually drives down their prices.
Wegovy is currently approved for chronic weight management in the United States. Novo Nordisk said it would ask regulators in the United States and Europe to clear the drug for additional medical indications as well, but did not say which ones.
Another version of the same drug made by Novo Nordisk, Ozempic, is approved for lowering blood sugar levels in adults with type 2 diabetes. A smaller trial found that Ozempic also reduced the risk of heart complications in diabetes patients.
Martin Holst Lange, the company’s executive vice president for development, said that the latest trial demonstrated the drug “has the potential to change how obesity is regarded and treated.”
Scientists said that it was not clear precisely how the drug cut people’s risk of heart complications.
The new class of obesity drugs has been shown to have some direct effects on blood vessels and the heart, including in studies finding that animals given the drugs are better able to survive heart attacks, said Dr. Daniel Drucker, a senior scientist at the Lunenfeld Tanenbaum Research Institute at Mt. Sinai Hospital in Toronto who helped identify the hormone that gave rise to the new drugs and been paid consulting or speaking fees by Novo Nordisk.
But they may also indirectly lower the risk of heart disease by reducing body weight, blood pressure or inflammation.
The new class of obesity drugs “has two shots on goal to improve cardiovascular health,” he said.
Further details from the new trial will allow researchers to study the relationship between how much weight patients lost and their cardiovascular benefits, potentially making clearer how Wegovy was improving people’s heart health.
“It’s really the beginning of a new chapter in improving the health of people with obesity,” Dr. Drucker said.
Even so, he said that the trial would also help researchers understand the incidence of side effects, especially given the size and duration of the study. Patients have reported nausea, diarrhea, vomiting, constipation and stomach pain, and some have stopped taking the medication because of these effects.
Experts said the trial could also change an approach to obesity that has long emphasized the responsibility of patients for fighting their own weight gains.
“Obesity’s not a personal choice — it’s not behavioral, it’s not something that people choose,” said Dr. Ania Jastreboff, an endocrinologist and obesity-medicine specialist at Yale University who was an investigator on the Wegovy trial and consults for makers of obesity drugs. “Medications like this, we believe, are potentially treating that underlying biology.”
The latest results, she said, “underscore the need to treat obesity as we treat any other disease.”