NASH or MASH: No Matter What You Call It, Madrigal’s FDA Approval Is a Big Deal

Philadelphia, PA – Thursday afternoon marked a major regulatory milestone. In one of the year’s most highly anticipated FDA decisions, the regulator approved Madrigal Pharmaceuticals’ Rezdiffra (resmetirom) as the first-ever therapy for the treatment of adults with noncirrhotic nonalcoholic steatohepatitis (NASH). Or was the approval for metabolic dysfunction-associated steatohepatitis (MASH)?

If you’re confused by the NASH versus MASH indication, you’re not alone. After all, the FDA’s announcement on Thursday invoked the NASH nomenclature. “NASH is a result of the progression of nonalcoholic fatty liver disease where liver inflammation, over time, can lead to liver scarring and liver dysfunction,” according to the agency. And yet, BioSpace and some other media outlets—though not all—reported Rezdiffra’s approval as being in MASH. Why the difference, you ask?

Months before Thursday’s FDA approval under the accelerated approval pathway, NASH was being referred to as MASH—and not just by some members of the trade press. As Madrigal explained in its announcement: NASH is also known as MASH. “In 2023, global liver disease medical societies and patient groups came together to rename the disease, with the goal of establishing an affirmative, non-stigmatizing name and diagnosis,” the company stated. And so, the NASH moniker became MASH.

Still, it didn’t stop Madrigal from using NASH in the headline of its press release on the FDA approval and throughout the biopharma’s announcement. I guess old habits die hard, even for a company “pursuing novel therapeutics” for NASH (they mean MASH!). Likewise, the nonprofit Global Liver Institute (GLI) couldn’t resist using the old name for the disease.

“NASH is most common among people with obesity and/or type 2 diabetes. As these conditions have become more prevalent, the risk for NASH also increased,” Jeff McIntyre, vice president of Liver Health Programs at GLI, said in a statement. “This approval gives patients and healthcare providers a long-awaited tool to change the trajectory of their chronic liver disease.”

No matter what you call it, Rezdiffra’s approval is a big deal for the estimated 6 million to 8 million people in the U.S. who have the condition with moderate to advanced liver scarring—a number that is expected to grow significantly. According to GLI, researchers anticipate 27 million cases in this country by 2030.

The FDA’s accelerated pathway for earlier approval of drugs that treat serious conditions and address an unmet medical need was sorely needed for this growing patient population, as once NASH/MASH progresses to significant liver fibrosis the risk of adverse liver outcomes increases dramatically.

Speaking with BioSpace ahead of the FDA’s decision on Thursday, experts said the approval could signal a sea-change in the diagnosis and treatment of MASH. “There are no effective approved therapies, and so Madrigal’s resmetirom, even though it has limited efficacy, would be an important first,” Rajarshi Banerjee, CEO of Perspectum, which supported Madrigal’s clinical trials, said.

For me, MASH—a leading cause of liver-related mortality—is personal. I lost my father to the disease, a complication of his diabetes. Though the approval of Rezdiffra comes too late for him, this medication is a breakthrough treatment, to be used along with diet and exercise, for a long-neglected patient population. As with any groundbreaking drug, it must be affordable and be made widely available to truly benefit the patients who need it most. That should be the next item on Madrigal’s agenda.

Greg Slabodkin is the news editor at BioSpace. You can reach him at [email protected].