OBJECTIVE: RE-EMBARK investigated etanercept (ETN) withdrawal and re-treatment in patients with non-radiographic axial spondyloarthritis (nr-axSpA) achieving inactive disease (ClinicalTrials.gov: NCT02509026). METHODS: Patients received ETN and background NSAID for 24 weeks in Period 1 (P1); those achieving inactive disease (Ankylosing Spondylitis Disease Activity Score with C-reactive protein [ASDAS-CRP] <1.3) discontinued ETN for ≤ 40 weeks (P2). Patients who flared (ASDAS with erythrocyte sedimentation rate [ASDAS-ESR] ≥ 2.1) were re-treated for 12 weeks in P3. Primary endpoint was proportion of patients with inactive disease who flared within 40 weeks of ETN withdrawal. Baseline characteristics were analyzed post hoc as predictors of maintenance and regain of inactive disease, respectively, using univariate logistic and stepwise multivariable logistic regression models. RESULTS: The proportion of patients experiencing flare following ETN withdrawal (P2) increased from 22.3% (25/112) after 4 weeks to 67.0% (77/115) after 40 weeks; 74.8% (86/115) experienced flare at any time during P2. Median time to flare was 16.1 weeks. Most patients (62.1% [54/87]) re-treated with ETN in P3 re-achieved inactive disease. Absence of both sacroiliitis detected on magnetic resonance imaging (MRI) and high sensitivity CRP (hs-CRP) > 88 3 mg/l at baseline predicted inactive disease maintenance in P2 following ETN withdrawal in multivariable analysis; male sex and age < 40 years predicted regaining inactive disease in P3 after flare/re-treatment. There were no unexpected safety signals. CONCLUSION: Approximately 25.2% maintained inactive disease for 40 weeks after discontinuing ETN. Absence of both MRI-sacroiliitis and high hs-CRP at baseline predicted response maintenance after ETN withdrawal.