WOMAC Meaningful Within-patient Change: Results From 3 Studies of Tanezumab in Patients With Moderate-to-severe Osteoarthritis of the Hip or Knee

J Rheumatol. 2022 Jun;49(6):615-621. doi: 10.3899/jrheum.210543. Epub 2022 Mar 1.


Objective: To define meaningful within-patient change (MWPC) in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).

Methods: Data were analyzed separately from 3 phase III clinical trials (ClinicalTrials.gov: NCT02697773, NCT02709486, NCT02528188) of tanezumab, a novel treatment intended for the relief of signs and symptoms of moderate-to-severe osteoarthritis (OA), administered subcutaneously every 8 weeks. Patients with moderate-to-severe OA of the hip or knee completed the WOMAC and patient global assessment of OA (PGA-OA) at regular timepoints. A repeated measures longitudinal model with change in WOMAC Pain, Physical Function, or Stiffness domain score as the outcome and change in PGA-OA as the anchor was used to establish MWPC for WOMAC domains.

Results: In the 3 studies, there were 688, 844, and 2948 subjects available for analyses, respectively. Analysis showed that a linear relationship between changes in WOMAC domains and changes in PGA-OA was supported and justified. Moreover, the relationships between these changes were very similar for 2 trials and close for the third. The estimated MWPC for the 3 WOMAC domains were from 0.84-1.16 (0-10 numerical rating scale) and from 12.50-16.23%, depending on study and domain, that corresponded to a 1-category change on PGA-OA. For a 2-category change those values were from 1.68-2.31 and from 25.01-32.46%, respectively.

Conclusion: These results establish MWPCs for WOMAC domains, at the individual patient level, for patients with moderate-to-severe OA of the hip or knee. [ClinicalTrials.gov: NCT02697773, NCT02709486, and NCT02528188].

Keywords: clinical trials; osteoarthritis; outcomes; pain.

Publication types

  • Clinical Trial, Phase III
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Monoclonal, Humanized
  • Double-Blind Method
  • Humans
  • Osteoarthritis, Hip* / drug therapy
  • Osteoarthritis, Knee* / drug therapy
  • Pain Measurement
  • Prostaglandins A / therapeutic use
  • Treatment Outcome


  • Antibodies, Monoclonal, Humanized
  • Prostaglandins A
  • tanezumab

Associated data

  • ClinicalTrials.gov/NCT02528188
  • ClinicalTrials.gov/NCT02709486
  • ClinicalTrials.gov/NCT02697773