What newer drug options are available for treating metabolic dysfunction‑associated fatty liver disease (MAFLD) in adults after implementing weight loss, diet, and exercise?

Newer Drugs for MAFLD

Resmetirom is the only FDA-approved liver-directed therapy for MAFLD and should be considered for adults with non-cirrhotic MASH and significant fibrosis (stage F2-F3), as it demonstrated histological efficacy on steatohepatitis and fibrosis in phase III trials with acceptable safety. 1, 2

Primary Pharmacological Recommendation

Resmetirom is the first-line pharmacological option for MAFLD/MASH after lifestyle interventions have been implemented:

• Target population: Non-cirrhotic adults with MASH and moderate to advanced fibrosis (F2-F3) 1, 2
• Dosing: Weight-based—80 mg for patients <100 kg; 100 mg for patients ≥100 kg 2
• Mechanism: Thyroid hormone receptor-β agonist that improves hepatic lipid metabolism 3
• Evidence strength: Large phase III MAESTRO-NASH trial demonstrated resolution of steatohepatitis without worsening fibrosis 2

Important Caveats for Resmetirom

The FDA label excludes patients with:

• Cirrhosis (any stage F4) 1, 2
• Early fibrosis (F0-F1) 2

No liver biopsy is required for initiation—non-invasive tests can identify appropriate candidates 2. However, long-term data on sustainability of histological benefits, liver-related outcomes, and safety remain unavailable 1.

Agents That Cannot Currently Be Recommended

GLP-1 Receptor Agonists

Despite promising metabolic benefits, GLP-1RAs cannot currently be recommended as MASH-targeted therapies because they lack formal demonstration of histological improvement in large, well-conducted phase III trials 1. This is a critical distinction—while these agents show:

• Significant improvements in body weight, insulin resistance, and liver parameters in phase II trials 4, 5
• Indirect improvements in liver fat content and biomarkers 4
• Benefits for obesity and type 2 diabetes management 6

The absence of phase III histological endpoints means they should not be used as primary MASH therapy, though they remain valuable for managing metabolic comorbidities 1, 5.

Vitamin E

Vitamin E cannot be recommended as MASH-targeted therapy due to:

• Lack of robust demonstration of histological efficacy from large phase III trials 1
• Potential long-term safety risks 1

Nutraceuticals

Nutraceuticals cannot be recommended due to insufficient evidence of effectiveness in reducing liver damage/fibrosis and unclear safety profiles 1.

Emerging Therapies in Development

Multiple agents are in late-stage clinical development but not yet approved 3, 7:

• Dual GLP-1/GIP agonists (e.g., tirzepatide): Showing considerable improvements in liver fat and histology in phase II studies 4, 5
• Triple agonists (GLP-1/GIP/glucagon): Promising phase II data 4, 5
• FGF-21 analogues: Under investigation 3
• Pan-PPAR agonists: In clinical trials 3
• FASN inhibitors: Early development 3

These agents show promise but cannot be recommended until phase III data demonstrate histological efficacy on the FDA-required endpoints (steatohepatitis resolution without worsening fibrosis, or fibrosis improvement without worsening steatohepatitis) 1, 2.

Clinical Algorithm for Drug Selection

Step 1: Confirm non-cirrhotic MASH with F2-F3 fibrosis using non-invasive tests or biopsy 2

Step 2: If locally approved and patient meets criteria → Initiate resmetirom 1, 2

Step 3: If patient has cirrhosis (F4) → No MASH-targeted pharmacotherapy currently recommended 1

Step 4: If patient has F0-F1 fibrosis → Continue lifestyle interventions; pharmacotherapy not indicated 2

Step 5: Manage metabolic comorbidities (obesity, T2DM) with appropriate agents (GLP-1RAs, metformin, etc.) as adjunctive therapy, but not as primary MASH treatment 6, 8

Common Pitfalls to Avoid

• Do not use GLP-1RAs as primary MASH therapy despite their metabolic benefits—they lack phase III histological data 1
• Do not treat cirrhotic patients with current MASH-targeted therapies—no evidence supports this 1
• Do not rely on vitamin E as first-line therapy given safety concerns and lack of robust phase III data 1
• Do not prescribe resmetirom for early fibrosis (F0-F1)—it is not indicated and lifestyle modification remains primary 2

The landscape is rapidly evolving, with multiple promising agents expected within the next decade, but resmetirom remains the only evidence-based pharmacological option with regulatory approval for MASH-targeted therapy at this time 1, 2, 3.