Is empirical resmetirom appropriate for patients with fatty liver and elevated SGPT (serum glutamate pyruvate transaminase) when elastography is not available?

Empirical Resmetirom Without Elastography is NOT Recommended

Resmetirom should not be initiated empirically in patients with fatty liver and elevated SGPT when elastography is unavailable, as proper patient selection requires noninvasive fibrosis assessment to identify F2-F3 fibrosis and exclude cirrhosis. 1, 2

Why Elastography or Alternative Fibrosis Assessment is Essential

The FDA approval of resmetirom is specifically for noncirrhotic MASH with moderate to advanced fibrosis (F2-F3 stage) 1, 2. Simply having fatty liver with elevated transaminases does not meet treatment criteria, as:

• Most patients with fatty liver have F0-F1 fibrosis and are excluded from treatment 1
• Patients with cirrhosis (F4) are also excluded and may require different dosing 1, 2
• The drug was studied only in patients with confirmed F2-F3 fibrosis 1

Alternative Approaches When Elastography is Unavailable

If vibration-controlled transient elastography (VCTE) or MR elastography (MRE) are not available, you have several options:

Use Simple Blood-Based Scores First

• FIB-4 score or NAFLD Fibrosis Score (NFS) can be calculated from routine labs 3
• FIB-4 < 1.3 (or < 2.0 if age >65) rules out advanced fibrosis with high negative predictive value 3
• These patients can be reassured and do NOT need resmetirom

For Indeterminate or High-Risk Scores

If FIB-4 is indeterminate or elevated:

1. Enhanced Liver Fibrosis (ELF) test - a blood-based collagen biomarker 1, 3

   • When used in isolation (without elastography), use cutoff of ≥9.8 to reduce false positives 1
   • ELF 9.2-9.7 requires additional testing before treatment 1
   • ELF >11.3 suggests cirrhosis - do not treat 1

2. Refer for elastography at a center where it's available 3

3. Consider liver biopsy if ELF alone shows 9.8-11.3 and you strongly suspect F2-F3 disease 1

Recommended Treatment Thresholds (When Elastography Available)

For context, the expert panel recommends treating when 1:

• VCTE 10-15 kPa OR
• MRE 3.3-4.2 kPa OR
• ELF 9.2-10.4 (with confirmatory test) OR
• ELF ≥9.8 (if used alone)

AND platelets ≥140 × 10⁹/L with no portal hypertension

Critical Safety Concerns with Empirical Use

Starting resmetirom without proper fibrosis staging risks:

1. Treating patients who don't need it (F0-F1 disease) - exposing them to unnecessary adverse effects including diarrhea, nausea, and potential hepatotoxicity 1

2. Treating cirrhotic patients (F4) - who were excluded from trials and may have different safety profiles 1, 2

3. Inability to monitor response - treatment response assessment requires either MRI-PDFF (30% reduction) or repeat elastography 1, which you won't have baseline values for

4. Drug-induced liver injury risk - requires liver enzyme monitoring at 12 weeks 1, but elevated baseline SGPT makes interpretation challenging

The Bottom Line Algorithm

For patients with fatty liver and elevated SGPT:

1. Calculate FIB-4 score (free, uses routine labs)
2. If FIB-4 low-risk → No treatment needed
3. If FIB-4 indeterminate/high → Order ELF test or refer for elastography
4. If ELF ≥9.8 and <11.3 with platelets ≥140 → Consider treatment (ideally confirm with second test)
5. If no access to ELF or elastography → Refer to hepatology for proper staging before initiating therapy

Do not start resmetirom empirically based solely on steatosis and elevated transaminases. The risk of inappropriate patient selection outweighs potential benefits, and proper noninvasive testing is required per FDA labeling and expert guidelines 1, 2.