BACKGROUND AND AIM: The MAESTRO-NASH phase 3 trial reported that a 52-week treatment of Resmetirom is effective in improving fibrosis and metabolic dysfunction-associated steatohepatitis (MASH) in patients with MASH and F2 or F3 fibrosis, while data on the impact on 5-year and long-term clinical outcomes are still lacking. We simulated the transition probabilities of disease progression in MASLD patients with F2 or F3 fibrosis and the effect of Resmetirom treatment on clinical outcomes. METHODS: A meta-analysis of literature data formed transition matrices for fibrosis stages and complications, defined as compensated (CC) and decompensated cirrhosis (DC), hepatocellular carcinoma (HCC) and mortality-liver-related mortality (LR-M), cardiovascular mortality (CV-M) and extra-hepatic cancer mortality (EHC-M). Markov model was developed to depict the F2 and F3 fibrosis stage progression towards the complications and to evaluate the effect of Resmetirom treatment on the natural history of MASLD. RESULTS: We estimated the 5-year probability of Resmetirom-treated and untreated MASLD patients with baseline F2 fibrosis of developing CC (5.16% vs. 6.82%, respectively), DC (0.25% vs. 0.3%, respectively), HCC (0.25% vs. 0.32%, respectively) and mortality (0.15% vs. 0.16% for LR-M
1.02% vs. 1.1% for CV-M
1.07% vs. 1.2% for EHC-M, respectively). Similarly, we estimated the five-year probability of Resmetirom-treated and untreated MASLD patients with baseline F3 fibrosis of developing CC (17.12% vs. 21.34%, respectively), DC(1.1% vs. 1.47%, respectively), HCC (1.21% vs. 1.73%, respectively) and mortality (0.59% vs. 0.91% for LR-M, 1.92% vs. 2.14% for CV-M and 1.04% vs. 1.14% for EHC-M, respectively). Life Years Gained (LYG) of Resmetirom-treated patients were 0.45 and 0.63 in MASLD patients with F2 and F3 fibrosis, respectively, and the model was sensitive to changes in Resmetirom efficacy and transition probabilities. CONCLUSIONS: Resmetirom decreases the 5-year and lifetime Markov-model estimated risk of CC, DC, HCC and liver-related mortality in patients with MASLD and F2 or F3 fibrosis.