Japan approves Wegovy for MASH, the country's first treatment for the liver disease

Japan's Ministry of Health, Labour and Welfare has approved Wegovy subcutaneous injection for metabolic dysfunction-associated steatohepatitis (MASH) without cirrhosis in patients with moderate to advanced fibrosis, according to an announcement from Sumitomo Pharma, which co-promotes the drug in Japan with Novo Nordisk Pharma ^[1]. The companies said it is the first approved treatment for MASH in Japan ^[1].

The decision is a partial change to Wegovy's existing manufacturing and marketing authorization in Japan, and it covers Wegovy Subcutaneous Injection SD and MD. The medicine's generic name is semaglutide, and it is given once a week ^[1].

The approval rests on Part 1 of the Phase 3 ESSENCE study, which enrolled adults with MASH and moderate to advanced fibrosis, defined as stage F2 or F3 ^[1]. At week 72, improvement in liver fibrosis without worsening of MASH was seen in 36.8% of patients taking semaglutide 2.4 mg, compared with 22.4% of those taking placebo. Resolution of MASH without worsening of liver fibrosis was seen in 62.9% of the semaglutide group, compared with 34.3% of the placebo group. Both results were statistically significant compared with placebo, and the safety profile was consistent with earlier data, with no new safety concerns identified ^[1].

The full ESSENCE study is designed to randomize 1,200 patients in a 2:1 ratio to semaglutide 2.4 mg or placebo, added on top of standard care, for 240 weeks. The application was submitted based on an interim analysis of the first 800 randomized patients ^[1].

MASH is a progressive liver disease that often causes few symptoms in its early stages but can lead to irreversible fibrosis, liver failure and liver cancer ^[1]. Prevalence in Japan is estimated at about 3.0%, and the five-year relative survival rate for patients who develop liver cancer is 35.8% ^[1]. The disease is also associated with cardiovascular disease and with cancers outside the liver, including colorectal and breast cancers ^[1].

In the United States, Novo Nordisk filed oral semaglutide 25 mg with the Food and Drug Administration for MASH during the second quarter of 2026, according to a GLP-1 pipeline update from Prime Therapeutics ^[2]. That August 2026 update included no FDA decision date ^[2]. The patient population covered by the US filing, and how it compares with the Japanese indication, have not been reported.

Why it matters for patients

The approval applies in Japan and does not by itself change what is available or covered in the United States. Any US use of semaglutide for MASH would depend on a separate FDA review, and a filed application is not an approval ^[2].

The Japanese indication is narrow. It covers adults without cirrhosis who have moderate to advanced fibrosis, so it does not describe treatment for patients whose liver disease has progressed to cirrhosis ^[1]. Whether semaglutide helps that group has not been reported.

The trial measured two different outcomes: less fibrosis without worsening steatohepatitis, and cleared steatohepatitis without worsening fibrosis ^[1]. Those are 72-week biopsy results, not proof that the drug prevents liver failure, liver cancer or death. That question is still being tested in the same study.

Because Japan and the United States run separate reviews, an approval in one country does not predict the timing or outcome of a decision in the other. The US filing is for oral semaglutide 25 mg, a different product from the once-weekly Wegovy injection approved in Japan ^[1][2].

What happens next

Part 2 of the ESSENCE study is ongoing. It is testing whether semaglutide 2.4 mg reduces the risk of liver-related clinical events at week 240 compared with placebo in adults with MASH and moderate to advanced fibrosis. Study completion is expected in 2029 ^[1].

The FDA review of oral semaglutide 25 mg for MASH had no announced decision timeline as of the August 2026 pipeline update ^[2]. No US approval for a semaglutide MASH indication has been announced.