SOURCE-LINKED STUDY SUMMARY
Semaglutide for Knee Osteoarthritis: STEP 9 Results
PED EVIDENCE INTERPRETATION
Did semaglutide improve knee pain as well as weight?
In adults with obesity and painful knee osteoarthritis, semaglutide produced greater weight loss and pain improvement than placebo at 68 weeks. WOMAC pain scores fell 41.7 versus 27.5 points; lower scores indicate less pain. [1]
- Design
- Double-blind randomized STEP 9 trial; 407 participants
- Population
- Obesity and moderate knee osteoarthritis with at least moderate pain; 81.6% women
- Comparison
- Subcutaneous semaglutide 2.4 mg weekly vs placebo; both with lifestyle counseling
- Duration
- 68 weeks
The evidence at a glance
| Outcome | Semaglutide | Placebo | Interpretation |
|---|---|---|---|
| Body-weight change [1] | −13.7% | −3.2% | P < .001 |
| WOMAC pain, 0–100 [1] | −41.7 points | −27.5 points | Lower is better; P < .001 |
| SF-36 physical function, 0–100 [1] | +12.0 points | +6.5 points | Higher is better; P < .001 |
| Stopped regimen because of adverse events [1] | 6.7% | 3.0% | Gastrointestinal disorders were the commonest reason |
OUR READING OF THE EVIDENCE
What this changes
This adds patient-reported pain and function outcomes to the weight-loss finding in the population studied. [1]
What it does not establish
It does not establish the same benefit in people without obesity, other joints, or other osteoarthritis severity. Structural joint repair was not established. [1]
Put it in context
Sources and transparency
Funded by Novo Nordisk. Abstract-based interpretation; not an independent assessment of all adverse events or methodological quality. [1]
Questions this study helps answer
Did semaglutide repair cartilage?
The reported results establish improvements in pain and physical function, not cartilage regeneration. They do not prove a direct joint-repair mechanism. [1]
Does this apply to knee pain without obesity?
The trial enrolled people with obesity and specified knee osteoarthritis. Its results should not automatically be transferred to other causes of knee pain or people outside that population. [1]
Original compact summary and study details
- What was studied
- A double-blind randomized trial tested weekly semaglutide plus lifestyle counseling versus placebo for obesity with painful knee osteoarthritis.
- Who / model studied
- Participants had obesity, radiologically confirmed moderate knee osteoarthritis, and at least moderate pain.
- Studied dose & schedule
- Dose and schedule have not yet been extracted for this summary.
- What the study found
- Semaglutide produced greater reductions in body weight and WOMAC pain than placebo by the end of treatment.
- Limitations & context
- Permanent treatment discontinuation was more frequent with semaglutide, most commonly because of gastrointestinal disorders.
Read summary source ↗ · Prepared 9/16/2026 · AI-assisted, source-based summary
Review record & corrections
Summary prepared: . Source scope: abstract. This is an AI-assisted source summary, not an independent clinician sign-off.
No public field-by-field revision history is available for this card yet. The date above is the summary date, not proof that every field was updated then.
Inspect the source · Correction policyResearch findings apply to the population and conditions studied. This educational summary is not a treatment recommendation or a formal assessment of study quality.
Original publication ↗ · DOI: 10.1056/nejmoa2403664