Resmetirom

Resmetirom is a landmark pharmaceutical agent approved by the U.S. FDA in 2024 as the first drug for the treatment of non-alcoholic steatohepatitis (NASH), specifically indicated for patients with stage F2 and F3 liver fibrosis . As a selective THR-β agonist, Resmetirom functions by activating the thyroid hormone receptor β in the liver, thereby reducing hepatic lipid accumulation, lowering cholesterol, and improving fibrosis markers . The favorable safety and efficacy profile of Resmetirom has generated substantial market demand, positioning it as a transformative therapy in hepatology . In quality control and regulatory contexts, Resmetirom and its related substances (such as Resmetirom Impurity 44, CAS NA) serve as essential reference standards for analytical method development, impurity profiling, method validation (AMV), and Abbreviated New Drug Application (ANDA) filings . The unique structural features of Resmetirom—particularly the pyridazinone core and the dichlorophenyl-triazine-dione arrangement—provide a rigid, conformationally constrained scaffold that facilitates high-affinity binding to THR-β, making this compound a benchmark for developing next-generation liver-targeted THR-β agonists.

 Product Parameters

MASH targeted drug

Resmetirom was initially developed by Roche and subsequently completed by Madrigal Pharmaceuticals in the United States; it received FDA approval for marketing in March 2024 for the treatment of non-cirrhotic MASH (formerly non-alcoholic steatohepatitis NASH) patients with intermediate to advanced liver fibrosis (F2–F3 stages). This marks the first and currently only drug approved globally for treating non-cirrhotic NASH/MASH in adult patients with moderate to severe liver fibrosis (F2–F3 stages). The approval of resmetirom represents a significant breakthrough in the field of NASH treatment, providing a new targeted therapeutic option for this complex disease and holding promise for improving patients' long-term prognosis. Currently, resmetirom has not yet been approved for marketing in China nor is it covered by medical insurance reimbursement schemes. However, its introduction to the Chinese market is progressing, which is expected to bring new hope for NASH patients in China and further advance the progress of metabolic liver disease treatment in the country.

Mechanism Of Action

Resmetirom is a partial agonist of the thyroid hormone receptor-β (THR-β). In in vitro assays evaluating THR-β activation activity, resmetirom demonstrated an efficacy of 83.8% compared with triiodothyronine (T3), with an EC50 value of 0.21 μM. In parallel functional assays targeting the thyroid hormone receptor-α (THR-α), resmetirom exhibited an efficacy of 48.6% relative to T3, with an EC50 value of 3.74 μM. THR-β represents the predominant subtype of thyroid hormone receptors in the liver, and its activation can reduce hepatic triglyceride levels; conversely, the effects of thyroid hormones outside the liver (e.g., in the heart and skeletal muscles) are primarily mediated by THR-α.

Bioactivity

Resmetirom (MGL-3196, VIA-3196) is a liver-targeted, orally active, and selective thyroid hormone receptor β (THR-β) agonist with an EC₅₀ of 0.21 μM, exhibiting 28-fold selectivity for THR-β over THR-α.

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Your search for a reliable Resmetirom supply partner—whether for API manufacturing, reference standard requirements, or drug development programs—should be straightforward. At Cosperpharm, we combine scientific excellence, regulatory expertise, and supply chain reliability to deliver the quality you need, precisely when you need it. Contact our customer service team today to discuss your specific requirements, request a quotation, or schedule a technical consultation.