Only one THR-beta agonist is currently approved, but more options may be available in the future.
Although resmetirom is the only FDA-approved THR-beta agonist currently available, “There is one ongoing phase 2b clinical trial for a different THR-beta agonist and at least a few others that are still in preclinical stages,” says Vincent Chen, MD, an assistant professor of internal medicine at the University of Michigan Medical School in Brighton. And different drugs may also be coming down the pike to help treat MASH.
Resmetirom is available now, but its clinical trial is still ongoing, says Na Li, MD, PhD, a hepatologist at The Ohio State University Wexner Medical Center in Columbus. This means the drug has to continue to be evaluated for safety and efficacy before it receives final approval.
1. THR-beta agonists don’t treat cirrhosis.
Cirrhosis is a severe form of liver scarring that occurs when healthy liver tissue is replaced by scar tissue. MASH can lead to cirrhosis, because the fat accumulation and inflammation in the liver can cause permanent scarring (fibrosis). But resmetirom can only reduce fibrosis in the earlier stages of liver disease and slow down its progress. It has not been shown to reverse existing cirrhosis. “People with cirrhosis should not take resmetirom, because we don’t know if it can help them,” says Chen.
That said, “There is an ongoing clinical trial looking at resmetirom in people with cirrhosis, so we should find out more in a few years,” he says.
2. Treatment side effects are usually mild.
“Common side effects include nausea, diarrhea, and elevated liver enzymes,” says Dr. Li. These effects usually go away as your body adjusts to the medication. In rare cases, gallbladder problems can occur.
Your doctor will monitor you for potential side effects and check your liver function to make sure the treatment is working well for you. Testing with bloodwork should occur every three to six months.
3. The treatment comes in pill form.
Resmetirom is a pill taken by mouth once a day, with or without food. It should be taken around the same time each day.
The exact dosing varies from person to person, so be sure to follow your doctor's instructions, according to MedlinePlus, especially to avoid any potential interactions with other medications you’re taking.
4. THR-beta agonists should be used in combination with a healthy lifestyle.
MASH often occurs in people who have other health conditions, such as:
- Diabetes
- High blood pressure
- High cholesterol
- Obesity
Exercising regularly and eating a healthy diet can help reduce liver fat and decrease inflammation, according to research — and help improve other health conditions you may have, too.
5. A THR-beta agonist can often be combined with treatments for other conditions.
You most likely won’t have to avoid any other medications if you’re taking resmetirom, Li says. But your doctor may want to monitor you for possible drug interactions if you’re taking medications such as statins or clopidogrel.
Be sure your doctor has a full list of the medications and supplements you take, including ones that are over the counter, so they can watch for any possible issues.
Self-Reflection
- Am I doing everything I can to support liver health with my lifestyle choices?
- What do I hope to gain from this treatment?
- Are the side effects worth the benefits?
- Would I be able to consistently take a pill around the same time each day?
Doctor Discussion
- How severe is the inflammation and scarring in my liver?
- Do you think a THR-beta agonist is a good choice for me?
- Could any of the other medications I take interact with this drug?
- What side effects should I report experiencing?
- How long will I need to be on this medication?
- If this drug doesn’t work, what are the next steps?
- Are there any THR-beta agonist clinical trials I should consider joining?
- What else can I do to help manage MASH?
Jonathan G. Stine, MD, MSc, FACP
Medical Reviewer
Jonathan Stine, MD, MSc, FACP, is an associate professor of medicine and public health science at Penn State in State College, Pennsylvania.
As an internationally recognized liver expert with a research and clinical focus on metabolic dysfunction–associated steatotic liver disease (MASLD) and exercise, he has authored more than 100 peer-reviewed papers, including multinational consensus guidelines.
Dr. Stine is the recipient of multiple research grants and awards from the American Association for the Study of Liver Diseases and the American Cancer Society, and has maintained continuous funding from the National Institutes of Health since 2018.
Stine is the MASLD consultant to the American College of Sports Medicine’s “Exercise is Medicine” initiative, and recently co-chaired the International Roundtable on MASLD and Physical Activity for ACSM. He serves as the Fatty Liver Program director as well as the Liver Center Research director for Penn State.
