CNN  — 

The US Food and Drug Administration has approved the first medication for a common form of liver inflammation called nonalcoholic steatohepatitis, or NASH, the agency said Thursday.

NASH – also known as metabolic dysfunction-associated steatohepatitis, or MASH – happens when the liver becomes inflamed because of excess fat cells. It’s an advanced form of nonalcoholic fatty liver disease. About 6 million to 8 million people in the US are thought to have NASH with moderate to advanced liver fibrosis, or scarring, the FDA says. Other complications associated with the condition include cirrhosis, liver failure and liver cancer.

Previous NASH treatment regimens focused on weight loss through lifestyle changes such as blood sugar control, a healthy diet and regular exercise.

The new medication, Madrigal Pharmaceuticals’ resmetirom, will be marketed under the brand name Rezdiffra. It received Breakthrough Therapy designation from the FDA in April. This status expedites the development and review of drugs that are intended to treat a serious condition and that preliminary clinical evidence indicates may be a substantial improvement over available therapies.

The medication – which activates a thyroid hormone receptor in the liver to help reduce fat accumulation – is taken by mouth daily. It’s approved for people who have NASH with moderate to advanced fibrosis, and it’s intended to be used along with a healthy diet and exercise.

Clinical trial results published in February showed that more than 25% of participants taking 80 milligrams of resmetirom achieved NASH resolution with no worsening of fibrosis, as did almost 30% of those taking 100 mg and less than 10% of participants who got a placebo. The medication also helped lower LDL or “bad” cholesterol levels and liver enzyme levels.

Most of the adverse events reported in the trial were mild or moderate; diarrhea and nausea were most common. Rezdiffra can have “potentially significant” interactions with certain other drugs, most notably statins to lower cholesterol, the FDA noted.

Rezdiffra received what’s known as accelerated approval, and Madrigal must complete a post-approval study to verify the drug’s clinical benefit.

“I believe this approval milestone will bring new energy and momentum to the NASH community, accelerating our efforts to improve disease education, build care pathways, and expand investment in NASH research,” Wayne Eskridge, CEO of the Fatty Liver Foundation, said in a news release from Madrigal on Thursday.

Madrigal says that it expects Rezdiffra to be available next month and that it has set up an assistance program to help people who don’t have insurance access the drug.