MHRA has authorised resmetirom, marketed as Rezdiffra, for adults with metabolic dysfunction-associated steatohepatitis, or MASH, where disease has progressed to stage 2 or stage 3 fibrosis. The authorisations cover 60 mg, 80 mg and 100 mg film-coated tablets, and were granted on 3 June 2026 to Madrigal Pharmaceuticals EU Limited. MHRA said the decision marks the first approved medicine for patients with MASH and moderate to advanced liver fibrosis. (gov.uk) For policy and regulatory readers, the immediate point is that the UK now has a licensed medicine in a disease area where MHRA had not previously approved one for this patient group. That moves the issue from authorisation alone into the next questions of product information, appraisal and service adoption. (gov.uk)
MASH is described by MHRA as a liver disease in which fat builds up in the liver, leading to inflammation and damage to liver cells as non-alcoholic fatty liver disease progresses. The authorised indication is for adults who have inflammation and cell damage with moderate scarring, consistent with stage 2 fibrosis, or significant scarring, consistent with stage 3 fibrosis. (gov.uk) MHRA says resmetirom works by binding to and activating thyroid hormone receptor beta in hepatocytes. The agency states that this increases fat breakdown in the liver, reduces stored fat, and may help reduce inflammation and fibrosis while improving liver function. (gov.uk)
The approval was backed by a main study involving 917 adults with MASH and moderate or advanced liver fibrosis who received resmetirom or placebo for 12 months. MHRA reported that, depending on dose, about 26 to 30 per cent of patients on resmetirom achieved resolution of MASH with no worsening of fibrosis, compared with 10 per cent on placebo. (gov.uk) On a second endpoint, around 27 to 29 per cent of patients receiving resmetirom showed an improvement in liver fibrosis with no worsening of MASH, compared with 17 per cent in the placebo group. In practical terms, those trial results are the basis on which MHRA judged the medicine suitable for authorisation in the defined population. (gov.uk)
Resmetirom is taken orally. MHRA identified diarrhoea and nausea as the most common adverse reactions, each affecting more than 1 in 10 people, and said the medicine will remain under close post-authorisation monitoring for safety and effectiveness. (gov.uk) The regulator directs suspected side effects through the Yellow Card scheme, alongside advice to speak to a doctor, pharmacist or nurse. MHRA also said the Summary of Product Characteristics and patient leaflet will be published on the MHRA products website within seven days of approval, which is the next formal source for prescribing and patient-use detail. (gov.uk)
The authorisation was made under the International Recognition Procedure. MHRA guidance says the IRP has been in place since 1 January 2024, replacing earlier reliance arrangements and allowing the agency to use prior approvals from specified reference regulators including the EU, US, Australia, Canada, Japan, Switzerland and Singapore. (gov.uk) The same guidance makes clear that IRP is not automatic recognition. MHRA carries out a targeted assessment using the reference regulator's evaluation, but it retains authority to make a national decision and to reject an application where the evidence is not robust enough or where UK-specific issues arise. (gov.uk)
The authorisation does not, on its own, settle routine NHS access. Government guidance on introducing new medicines says licensing and health technology evaluation run as separate processes, and that NICE evaluates most new licensed medicines to decide whether routine funding is justified in England, with recommendations normally adopted in Wales and Northern Ireland. (gov.uk) For resmetirom, NICE lists an appraisal as in progress with expected publication on 10 June 2026. The immediate policy position is therefore clear: MHRA has completed the licensing step, but the funding and implementation picture is still moving through the next formal stage. (nice.org.uk)