Semaglutide in MASH (phase 2) — trial digest
Semaglutide in MASH (phase 2) (N Engl J Med 2021): Does semaglutide achieve resolution of steatohepatitis without worsening of fibrosis?
Citation and design
| Field | Value |
|---|---|
| Trial | Semaglutide in MASH (phase 2) |
| Intervention | Semaglutide 0.1, 0.2 and 0.4 mg daily |
| Publication | N Engl J Med, 2021 (first author Newsome) |
| Design | Double-blind, placebo-controlled, 72 weeks, with paired biopsies |
| Population | Adults with biopsy-confirmed steatohepatitis and fibrosis |
This digest summarises the trial and the criticisms our journal club considered material. It is not a substitute for the paper, and where the two differ the paper is right.
The question it set out to answer
Does semaglutide achieve resolution of steatohepatitis without worsening of fibrosis?
Stating the question before the result is a house convention. A great many arguments about this trial are actually arguments about what it was for.
What it found
A histological endpoint with paired biopsies, which is as close to a hard endpoint as this field gets.
Resolution of steatohepatitis was substantially more frequent on active treatment.
Improvement in fibrosis stage — the outcome most closely tied to long-term prognosis — did not differ significantly, and that is the result worth remembering.
Criticisms the journal club considered material
- Histological resolution is a surrogate for clinical outcomes such as cirrhosis and liver-related death.
- Biopsy reading is subject to sampling and observer variability even when centrally adjudicated.
- A daily dosing schedule not used elsewhere in the semaglutide programme, which complicates comparison.
These are criticisms of the design and of how the result is used, not of the investigators. Sessions that lose that distinction get moderated.
How it is misused
The two recurring misuses of this trial in general discussion are quoting the relative effect without the absolute one, and extending the result to a population the trial did not enrol. Both are easy to correct and both keep happening.
Where a number appears in secondary coverage without an estimand attached, assume it is whichever version is larger and check the paper.
Maintenance
Digests are reviewed when new analyses of the same trial are published, and at the review date shown above regardless. If a secondary publication changes the picture, raise it in journal club rather than editing the digest directly, so the change is discussed before it lands.
Revision history
| 2026-02-23 | v.szabo | Added the worked example that the review thread asked for. |
| 2025-11-07 | s.chowdhury | Restructured into shorter sections so the outline navigation is usable. |
| 2025-08-20 | policy_reader | Recorded a dissent from one maintainer rather than resolving it silently. |
| 2025-07-13 | e.dalgleish | Split an overlong section in two and gave the second a proper heading. |
| 2025-02-27 | a.thorne | Added the table of acceptance criteria requested in doc review. |
| 2024-11-24 | r.aldana_pharmd | Initial promotion from the source topic. Structure taken from the marked solution. |
Every edit to a maintained document records its author and a note explaining the change. An edit without a note may be reverted by any wiki editor under R9, and the revert is logged. Disagreements about content belong on the source topic rather than in the revision history (R10).
Related documents
- STEP 1 — trial digestSTEP 1 (N Engl J Med 2021): Does semaglutide 2.4 mg weekly reduce body weight in adults with obesity and no diabetes?
- STEP 2 — trial digestSTEP 2 (Lancet 2021): What weight reduction does semaglutide 2.4 mg achieve in people who also have type 2 diabetes?
- STEP 3 — trial digestSTEP 3 (JAMA 2021): What does semaglutide add on top of intensive behavioural therapy?
- STEP 4 — trial digestSTEP 4 (JAMA 2021): What happens if you stop after reaching the maintenance dose?
- STEP 8 — trial digestSTEP 8 (JAMA 2022): How does weekly semaglutide compare directly with daily liraglutide?