Two-year results of disease activity score (DAS)-remission-steered treatment strategies aiming at drug-free remission in early arthritis patients (the IMPROVED-study)

BACKGROUND: Early suppression of disease activity in (rheumatoid) arthritis (RA) patients may result in drug-free remission and prevent damage. We assessed 2-year clinical and radiological outcomes of two disease activity score (DAS)-remission-steered treatment strategies in early arthritis patients. METHODS: Patients (n = 610) with early RA or undifferentiated arthritis (UA) were treated with methotrexate (MTX) and tapered high dose of prednisone. Patients in early remission (44/53 joints DAS <1.6) after 4 months tapered and stopped medication. Patients who did not achieve early DAS-remission were randomized to either MTX plus hydroxychloroquine plus sulphasalazine plus low dose prednisone (arm 1) or to MTX + adalimumab (arm 2). At four-monthly intervals, medication was tapered and stopped if DAS was <1.6 but restarted, increased or switched if DAS was ≥1.6. Proportions of (drug-free) DAS-remission (DFR) after 2 years and Sharp-van der Heijde scores (SHS) were analyzed separately for the treatment strategies and patients with RA and UA. RESULTS: After 2 years, 301/610 (49 %) patients were in DAS-remission and 131/610 (21 %) in DFR. In the early remission group 241/387 patients (62 %) were in DAS-remission and 111/387 (29 %) DFR. In arm 1 22/83 (27 %) and in arm 2 24/78 (31 %) were in DAS-remission, and 6/83 (7 %) and 7/78 (9 %), respectively, were in DFR. RA and UA patients achieved DAS-remission in comparable percentages (RA: 234/479 (49 %), UA: 64/122 (52 %), p = 0.25). More UA patients achieved DFR (41/122 (34 %)) compared to RA patients (89/479 (19 %), p<0.001). Mean (SD) DAS over time was 1.74 (0.58) across all patients, and median (IQR) SHS progression was 0 (0–0). CONCLUSIONS: After 2 years remission-steered treatment in early RA and UA patients, DAS-remission and DFR percentages were relatively low. Patients who achieved early remission more often achieved (drug-free) remission after 2 years than patients who needed additional treatment steps in the randomization arms, and more UA than RA patients achieved DFR. Overall, disease activity and radiologic damage progression in all patients were well suppressed. TRIAL REGISTRATION: http://www.controlled-trials.com/ISRCTN11916566 Registered 07/11/2006 and EudraCT number 2006-06186-16 Registered 16/07/2007. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13075-015-0912-y) contains supplementary material, which is available to authorized users.