# Semaglutide in Knee Osteoarthritis: A Six-Month Cohort and Its Phenotypes In 88 knee osteoarthritis patients, six months of semaglutide came with 10.88 kg lost and WOMAC down 22.50 points, in a retrospective cohort with no comparison group and exploratory phenotype clusters. Publisher: This GLP Editorial Team Canonical: https://thisglp.com/research/semaglutide-knee-osteoarthritis-phenotypes Updated: 2026-09-18 Published: 2026-09-16 [← Research](https://thisglp.com/research) Evidence # Semaglutide in Knee Osteoarthritis: A Six-Month Cohort and Its Phenotypes Pain, function and inflammation markers all improved over six months on semaglutide in 88 patients. There was no untreated comparison group, and the authors say so in their methods. [This GLP Editorial Team](https://thisglp.com/about)September 20266 min readUpdated September 2026 Mean change at six months — everything moved · weight · −10.88 kg · pain, 0–10 scale · −2.47 points · WOMAC total · −22.50 points · C-reactive protein · −2.67 mg/L · sedimentation rate · −7.62 mm/h · Nobody was untreated, so nothing here is attributable. **Research, not medical advice.** This GLP is independent and educational. Nothing here is a substitute for individualized care from a licensed clinician, and reading it creates no doctor–patient relationship. Talk to your own provider before starting, stopping, or changing any medication, peptide, or therapy. See our [methodology](https://thisglp.com/methodology) and [terms](https://thisglp.com/terms). ## Key takeaways - 93 adults with knee osteoarthritis started semaglutide in routine rheumatology care; 88 completed six months. - Mean weight fell 10.88 kg, pain 2.47 points, WOMAC total 22.50 points. - Inflammatory markers fell too: C-reactive protein 2.67 mg/L, sedimentation rate 7.62 mm/h. - There was no untreated comparison group, and the authors say their results are therefore non-causal. - An exploratory clustering analysis sorted the 88 into response phenotypes. Every number in this study went the right way, and the authors wrote a sentence in their own methods that stops any of it being read as the drug’s doing. That sentence is worth more than the results, and it is the thing [the randomized knee trial](https://thisglp.com/research/do-glp1-drugs-help-knee-pain) has and this does not. ## What was measured A retrospective, self-controlled cohort of 93 adults with knee osteoarthritis and overweight or obesity, treated in routine rheumatology care. [\[1\]](https://thisglp.com/research/semaglutide-knee-osteoarthritis-phenotypes#ref-1) 88 completed six months. Pain on a visual analog scale, WOMAC function, anthropometry, inflammatory markers, glycated hemoglobin, lipids, dose exposure and safety were all tracked. At six months, mean weight had fallen 10.88 kg, pain by 2.47 points, WOMAC total by 22.50 points, C-reactive protein by 2.67 mg/L and sedimentation rate by 7.62 mm/h — the last two being inflammation markers rather than symptoms, and so [the easiest things here to move](https://thisglp.com/research/glp1-pcos-insulin-resistance). The methods section says it plainly “There was no untreated concurrent comparator; within-patient changes and exposure-outcome associations were therefore interpreted as non-causal.” Papers rarely disqualify their own headline that directly. It matters here more than usual, because every one of these outcomes moves on its own: knee pain fluctuates, people arrive at a clinic when they are at their worst, and taking 10.88 kg off a knee would improve WOMAC scores through mechanics alone. ## The phenotypes The authors also ran an exploratory K-means clustering across dose, weight loss, body mass index change, pain and WOMAC improvement, C-reactive protein, sedimentation rate and glycated hemoglobin, to sort patients into response patterns. K-means always returns clusters. Give it eight variables and 88 people and it will partition them, whether or not the groups mean anything. The authors call the analysis exploratory and examined how stable the solutions were under resampling, which is the right precaution — and a set of phenotypes found once in 88 people is a hypothesis, not a taxonomy, in the same way [a subgroup effect found once](https://thisglp.com/research/tirzepatide-fibrosis-worst-group) is. ## What it is good for Describing what happened to a real clinic’s patients over six months, which is genuinely useful and is not the same as showing what caused it. If you have knee osteoarthritis and are considering one of these drugs, the pain and function evidence worth weighing comes from the trial with a placebo arm. This cohort adds inflammatory markers and a picture of routine care, and it adds them with the caveat its own authors attached — which is more than [most real-world reports](https://thisglp.com/research/glp1-weight-loss-in-ordinary-care) manage. ## Frequently asked Did semaglutide improve knee pain here? Pain fell 2.47 points and WOMAC total 22.50 points over six months. The authors state there was no untreated comparator, so the changes are reported as non-causal. Why does a missing comparison group matter so much? Because knee pain fluctuates, people attend a clinic when they are worst, and losing 10.88 kg would improve knee scores mechanically. Without an untreated group, none of that can be separated from the drug. What are the response phenotypes? Clusters produced by an exploratory K-means analysis across eight variables in 88 patients. The method always returns clusters, and the authors treat the result as exploratory. Did inflammation improve? C-reactive protein fell 2.67 mg/L and sedimentation rate 7.62 mm/h, alongside the weight loss, in the same uncontrolled design. ## Sources 1. \[1\] Conforti A, et al. (2026). Beyond the Scale: Changes in Pain, Physical Function (WOMAC), and Low-Grade Inflammation Following Semaglutide Treatment in Patients with Knee Osteoarthritis-Results from a Six-Month Real-World Cohort Journal of Clinical Medicine. [PMID 42589980](https://pubmed.ncbi.nlm.nih.gov/42589980/) ## Where to get it ### Best GLP-1 injections Every injectable seller we can verify, with the price each one publishes and an honest read of what the trials measured. [Compare providers →](https://thisglp.com/best/compounded-semaglutide) ## More in Evidence - [ 150 minutes · Weekly activity goal · 2 days · Muscle strengthening · Adapt · Symptoms and ability ### Exercise on Ozempic: Building Strength Without Ignoring Symptoms ](https://thisglp.com/research/exercise-on-ozempic) - [ STEP 1, semaglutide 2.4 mg vs placebo, % change at 68 weeks · LDL cholesterol · −2.5% vs +1.3% · Total cholesterol · −3.3% vs +0.1% · HDL cholesterol · +5.2% vs +1.4% · Triglycerides · −21.9% vs −7.3% · Wegovy label, Table 13. Adults without diabetes. Ozempic doses are lower. ### Does Ozempic Lower Cholesterol? What the Lipid Results in the Trials Show ](https://thisglp.com/research/does-ozempic-lower-cholesterol) - [ Where the insulin reduction came from, units per day · week 4 · 13.4 total · week 26 · 21.9 · the drug itself · the weight loss · The drug’s own contribution barely moved: 11.1 then 11.4. · Everything added between weeks 4 and 26 came from weight. ### Does Semaglutide Help Type 1 Diabetes? What Two Small Trials Found ](https://thisglp.com/research/semaglutide-in-type-1-diabetes)