Wegovy Gets F.D.A. Approval for MASH

The Food and Drug Administration approved the weight loss drug Wegovy to treat an increasingly prevalent liver disease on Friday.

Roughly 15 million people — six percent of adults in the United States — have metabolic dysfunction-associated steatohepatitis, known as MASH. Rates of the disease are rising.

The condition occurs when fat builds up in the liver, which can trigger scarring, cell damage and inflammation. MASH can lead to liver cancer and even death; it is also one of the most common reasons Americans seek liver transplants.

Wegovy, which is a weekly injection, is now approved for adults with MASH and moderate-to-advanced levels of fibrosis, or excessive scar tissue in the liver. The drug is not intended for people with cirrhosis, a condition marked by severe liver scarring and damage. Novo Nordisk, the company that makes Wegovy and its sister drug, Ozempic, asked regulators to green-light the new approval after submitting data from a highly anticipated clinical trial. In the study, around 63 percent of people who took the drug saw fat and inflammation clear up in their livers, without worsening liver scarring, compared to about 34 percent of participants on a placebo.

“It’s definitely exciting, and helping move beyond the stigma that we’re just cosmetically treating weight,” said Dr. Andrew Kraftson, a clinical associate professor in the division of metabolism, endocrinology and diabetes at Michigan Medicine. “There are these metabolic benefits that we’re seeing with these medicines.”

Scientists don’t entirely understand how the drug helps treat MASH. It may, in part, be as simple as weight loss: MASH is closely linked with obesity, and Wegovy lowers body weight. But researchers think the drug may have other beneficial effects, like potentially reducing inflammation in the liver.

People taking Wegovy commonly experience gastrointestinal issues, especially in the first months on the drug. These can include nausea, vomiting, stomach pain, constipation and diarrhea. Some patients also report headaches, dizziness and fatigue. Doctors prescribing the drug for those with MASH will likely need to monitor patients to ensure they do not lose too much weight, Dr. Kraftson said.

There is currently one other drug on the market to treat MASH, Rezdiffra, a pill that activates a receptor in the liver to bring down inflammation and fat buildup. Bariatric surgery has also shown promise. Often, though, doctors encourage patients to lose weight — “but maybe not always giving them the tools,” Dr. Kraftson said.

Wegovy will be a welcome addition to the options doctors can prescribe — as long as their patients can access them. The drug carries a list price of over $1,300 a month, although most people do not pay that full amount. Many people have lost insurance coverage for weight-loss drugs, as plans struggle to keep up with the costs.

That may only become more challenging as more and more people qualify for these medications. This is the first time that Wegovy can be used on-label in patients who are not overweight or obese, which may broaden the pool of people who seek out the drug.

The list of conditions for which scientists are studying these drugs keeps growing. The F.D.A. approved Wegovy last year to reduce the risk of heart attacks and strokes in people who are overweight or obese; in January, the agency cleared Ozempic — which contains the same compound as Wegovy — to treat kidney disease in people with diabetes. Zepbound, a similar obesity medication from competitor Eli Lilly, won approval for people with obesity and sleep apnea in December.