Int J Rheum Dis. 2026 Sep;29(9):e70877. doi: 10.1111/1756-185x.70877.
ABSTRACT
AIM: Knee osteoarthritis causes major pain and disability, yet disease-modifying drugs remain limited. Tofacitinib, an oral Janus kinase (JAK) inhibitor, suppresses pro-inflammatory cytokine signaling implicated in osteoarthritis but is unexplored in the knee; we evaluated it versus placebo in early-grade disease.
METHODS: In this single-center, randomized, double-blind, placebo-controlled trial, 100 patients with Kellgren-Lawrence Grades 1 and 2 knee osteoarthritis were randomized to tofacitinib 11 mg extended-release once daily (n = 49) or placebo (n = 51) for 12 weeks. The primary outcome was change in VAS pain to Week 12; secondary outcomes were WOMAC, Oxford Knee Score, EQ-5D-5L, and analgesic use, assessed to Week 12 and a Month-6 follow-up, and analyzed by intention-to-treat with a mixed model for repeated measures.
RESULTS: Baseline characteristics were balanced. Both groups improved within-group during treatment (p < 0.001), but between-group differences were not significant; the Week-12 VAS effect (tofacitinib minus placebo) was +0.02 (95% CI -0.84 to 0.89), with WOMAC, Oxford Knee Score, and EQ-5D-5L likewise excluding their minimal clinically important differences. Improvements rebounded toward baseline by Month 6. Drug-related adverse events were more frequent with tofacitinib (14.3% vs. 0%, p = 0.005) but were gastrointestinal and self-limiting.
CONCLUSION: Tofacitinib was not superior to placebo in early-grade knee osteoarthritis, and the large within-group improvement rebounded toward baseline by 6 months, consistent with a predominantly non-specific (contextual) response. Because participants were selected radiographically without inflammatory phenotyping, these findings do not support tofacitinib in unselected early-grade disease but cannot exclude benefit in an inflammatory phenotype; future trials should stratify accordingly, with longer follow-up and structural outcomes.
TRIAL REGISTRATION: Clinical Trials Registry of India: CTRI/2025/07/090567.
PMID:42760593 | DOI:10.1111/1756-185x.70877
