Tapering and discontinuation of TNF-α blockers without disease relapse using ultrasonography as a tool to identify patients with rheumatoid arthritis in clinical and histological remission

Background: In this study, we assessed whether clinical and ultrasonography (US)-based remission could be used to select patients with rheumatoid arthritis (RA) eligible to taper and discontinue anti-TNF-alpha therapy after achievement of remission, looking at disease relapse. Methods: Forty-two patients with RA in sustained remission who were receiving anti-TNF-alpha treatment (Disease Activity Score <1.6 at three visits 3 months apart) underwent US evaluation of synovial hypertrophy (SH) and power Doppler (PD) signal presence. Five SH+/PD- patients with RA underwent US-guided knee synovial tissue biopsy to assess histological features of residual synovitis (CD68, CD3 and CD20 immunostaining) after sustained clinical remission was achieved. All patients were enrolled to taper first then discontinue anti-TNF-alpha. They were followed every 3 months afterwards, and the relapse rate was recorded. Results: Selected SH+/PD- patients showed low-grade synovitis as demonstrated by the presence of CD68+ cells in the lining layer and few infiltrating CD3+ and CD20+ cells at the time sustained clinical remission was achieved. After anti-TNF-alpha tapering, 13 patients (30.9 %) relapsed and 29 (69.1 %) SH+/PD- patients maintained disease remission after 3 months and discontinued anti-TNF-alpha treatment. Among them, 26 patients (89.7 %) maintained disease remission status after 6 months of follow-up. All patients who relapsed were retreated with the previous biologic, following the last effective therapeutic regimen, again reaching a good European League Against Rheumatism response within 3 months. Conclusions: US evaluation using PD signalling allows the identification of patients with RA in clinical and histological remission after tapering and discontinuing biologics.