Rezdiffra (Resmetirom) is NOT Appropriate for Your Patient
Your patient with a FibroScan liver stiffness of 6.6 kPa (F0 stage) does not meet eligibility criteria for Rezdiffra and should not be started on this medication. 1, 2
Why Your Patient is Ineligible
FDA Label Explicitly Excludes F0-F1 Fibrosis
The FDA approval for resmetirom specifically states it is indicated for "adults with noncirrhotic NASH (MASH) with moderate to advanced liver fibrosis (consistent with stages F2 to F3 fibrosis)" and "The label excludes patients with cirrhosis and those with early (F0-1) fibrosis." 1, 2
Your Patient's Fibrosis Stage
- Liver stiffness of 6.6 kPa corresponds to F0 stage (no fibrosis)
- The MAESTRO-NASH trial that led to FDA approval enrolled only patients with F2-F3 fibrosis (median baseline LSM was 12 kPa, Q1-Q3: 10-15 kPa) 2
- Treatment eligibility requires LSM ≥10 kPa according to expert consensus 1, 3
Who Actually Qualifies for Rezdiffra
Fibrosis Requirements (Must Meet ONE):
- VCTE (FibroScan) LSM: 10-20 kPa (with platelets ≥140×10⁹/L to exclude cirrhosis) 1, 3
- MRE: 3.1-4.4 kPa 3, 4
- ELF score: 9.2-11.3 3
- Biopsy-proven F2 or F3 fibrosis (though biopsy is not required by FDA label) 1, 2
Additional Requirements:
- Diagnosis of MASLD/MASH (your patient's CAP of 289 dB/m does suggest steatosis)
- Exclusion of other liver diseases (autoimmune hepatitis, viral hepatitis, significant alcohol use)
- Non-cirrhotic (LSM <20 kPa, platelets ≥140×10⁹/L)
- No active untreated thyroid disorders 1, 4
Critical Clinical Context
Why F2-F3 Fibrosis Matters
The rationale for restricting treatment to F2-F3 fibrosis is based on risk stratification for adverse outcomes. Patients with F0-F1 fibrosis have substantially lower risk of liver-related morbidity and mortality compared to those with significant fibrosis (≥F2). 1, 5 The AASLD guidance identifies patients with "at-risk MASH" (F2-F3 fibrosis) as "the population most likely to benefit from a treatment intervention." 1
The Evidence Base
The MAESTRO-NASH trial demonstrated that resmetirom achieved:
- MASH resolution without fibrosis worsening: 27-36% vs 13% placebo
- Fibrosis improvement without MASH worsening: 23-28% vs 13-15% placebo 2, 6
However, these benefits were demonstrated specifically in the F2-F3 population, and there is no evidence supporting efficacy or safety in F0-F1 patients. 6
What to Do Instead for Your Patient
Focus on Lifestyle and Metabolic Management:
- Weight loss through diet and exercise (target 7-10% body weight reduction)
- Optimize management of metabolic comorbidities (diabetes, hypertension, dyslipidemia)
- Consider GLP-1 receptor agonists (e.g., semaglutide) if patient has type 2 diabetes or obesity with additional metabolic risk factors 5, 4
- Discourage alcohol consumption 5
Surveillance Strategy:
- Repeat FibroScan in 1-2 years to monitor for fibrosis progression
- If LSM increases to ≥10 kPa on repeat testing, reassess eligibility for pharmacologic therapy 3
Common Pitfall to Avoid
Do not prescribe resmetirom based solely on steatosis (elevated CAP) without documented significant fibrosis. Recent real-world data shows that when NITs are used without histologic confirmation, there is substantial risk of both under-diagnosis and over-prescription. 7 In one biopsy-proven cohort, 44% of patients identified by NITs as eligible actually did not meet histologic criteria, leading to unnecessary treatment and cost. 7
Your patient's LSM of 6.6 kPa is well below the threshold for treatment consideration and represents minimal to no fibrosis risk.