Resmetirom

Resmetirom is used to treat metabolic dysfunction-associated steatohepatitis (MASH) in adults who have moderate to advanced liver scarring (fibrosis), but without liver cirrhosis. It is taken once a day alongside dietary and exercise changes. The brand name is Rezdiffra.

MASH (metabolic dysfunction-associated steatohepatitis) is a condition in which excess fat in the liver leads to inflammation and scarring. It was formerly known as NASH (nonalcoholic steatohepatitis); the name was changed to remove the potentially stigmatizing term "nonalcoholic."

Resmetirom works by targeting a specific liver receptor called THR-beta, helping to reduce fat buildup in liver cells. This can slow the progression of MASH. In clinical trials, patients taking resmetirom were 1.5 to 2 times more likely to see improvement in liver scarring and 2 to 3 times more likely to see a reduction in MASH compared to placebo. Improvements in liver enzymes were seen in as little as 3 months.

Resmetirom gained FDA approval on March 14, 2024, under the brand Rezdiffra made by Madrigal Pharmaceuticals. There is no generic.

• This approval was under the accelerated approval designation, which means continued approval may be contingent on a clinical benefit being shown in confirmatory trials.

• Take resmetirom exactly as your healthcare provider tells you to take it.
• Your dose is based on your body weight.
• Take resmetirom by mouth, 1 time a day, with or without food.
• Swallow resmetirom tablets whole. Do not split, crush, or chew the tablets,
• If you miss a dose of resmetirom, skip the missed dose and take your next dose at the regular time.

Before you take resmetirom, tell your healthcare provider about all of your medical conditions, including if you:

• Have any liver problems other than MASH
• Have gallbladder problems or have been told you have gallbladder problems, including gallstones
• Are taking other medications such as gemfibrozil to lower your cholesterol or cyclosporine to suppress your immune system, because some of these may not be recommended
• Are pregnant or plan to become pregnant
• Are breastfeeding or plan to breastfeed.

Pregnancy

It is not known if resmetirom will harm your unborn baby.

Pregnancy Safety Study. There is a pregnancy safety study for women who are or become pregnant during treatment with resmetirom. The purpose of this pregnancy safety study is to collect information about your health and your baby’s health. You or your healthcare provider can report your pregnancy by visiting https://pregnancyregistry.madrigalpharma.com/ or calling 1-800-905-0324.

Breastfeeding

It is not known if resmetirom passes into your breast milk. Talk to your healthcare provider about the best way to feed your baby while you are taking it.

The most common side effects of resmetirom are:

• Diarrhea
• Nausea
• Itching
• Stomach (abdominal) pain
• Vomiting
• Dizziness.
• Constipation.

Resmetirom may cause serious side effects, including:

• Liver injury (hepatotoxicity). Stop taking resmetirom and call your healthcare provider right away if you develop the following signs and symptoms of hepatotoxicity:
• Gallbladder problems. Gallbladder problems, such as gallstones, inflammation of the gallbladder, or inflammation of the pancreas from gallstones, can occur with MASH and may occur if you take resmetirom. Call your healthcare provider right away if you develop signs or symptoms of these conditions, including nausea, vomiting, fever, or pain in your stomach area (abdomen) that is severe and will not go away. The pain may be felt going from your abdomen to your back, and the pain may happen with or without vomiting.

It is not known if resmetirom is safe and effective in children under the age of 18.

These are not all the possible side effects of resmetirom. For more information, ask your healthcare provider or pharmacist. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects to www.fda.gov/medwatch.

Recommended Dose of Resmetirom for MASH

• Weight <100 kg: 80 mg orally once daily
• Weight ≥100 kg: 100 mg orally once daily.

Resmetirom works by partially activating a liver-specific receptor called THR-β, which helps reduce fat buildup in the liver. It strongly targets THR-β while having much less effect on THR-α, the receptor responsible for thyroid hormone activity in the heart and bones. This selective action means resmetirom can reduce liver fat with a lower risk of affecting other organs.

Resmetirom belongs to the drug class called thyroid hormone receptor-beta (THR-beta) agonists.

The cost for prescription drugs varies depending on your insurance plan and which pharmacy you use. Refer to our Drugs.com price guide page for more information about Rezdiffra Prices, Coupons, Copay Cards & Patient Assistance.

You may also be eligible for a Rezdiffra savings card or coupon. Ask your doctor or pharmacist if you qualify.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Resmetirom and other medicines may affect each other, causing side effects, or resmetirom may affect the way other medicines work, and other medicines may affect how it works.

Especially tell your healthcare provider if you take medicines that contain gemfibrozil to help lower your triglycerides because resmetirom is not recommended in patients taking these medicines.

Tell your healthcare provider if you are taking medicines such as clopidogrel to thin your blood or statin medicines to help lower your cholesterol.

This is not a complete list of interactions. Know the medicines you take. Keep a list of them to show your healthcare provider and pharmacist when you get a new medicine.

Store resmetirom at room temperature between 68ºF and 77ºF (20ºC and 25ºC).

Active ingredient: resmetirom.

Inactive ingredients: colloidal silicon dioxide, croscarmellose sodium, magnesium stearate, mannitol, and microcrystalline cellulose.

Film coating: polyethylene glycol, polyvinyl alcohol, talc, titanium dioxide, red iron oxide (100 mg tablets), and yellow iron oxide (80 mg and 100 mg tablets).

Resmetirom is manufactured and distributed by Madrigal Pharmaceuticals, West Conshohocken, PA, under the brand name Rezdiffra.