Background Biologic diseasemodifying antirheumatic drugs (bDMARDs) that target cytokines and cytokine receptors such as tumor necrosis factor (TNF)alpha and interleukin (IL)6 have been established as a standard therapy of rheumatoid arthritis (RA) for patients with conventional systemic DMARDs, such as methotrexate (MTX), resistant disease. Golimumab, one of the bDMARDs, is an antibody targeting to TNF-alpha. In Japan, we can choose the dose of golimumab 50mg or 100mg according to the disease activity. Recent advance of ultrasound (US) equipment allows obtaining high-quality gray-scale (GS) imaging and sensitive power Doppler (PD) assessment, especially at small joints of the hands and feet. To date, US is the most sensitive imaging modality available in daily rheumatology practice for the assessment of residual synovitis.

Objectives The aim of this study was to compare the ultrasound findings between patients with rheumatoid arthritis (RA) treated by golimumab 100mg and 50mg.

Methods Patients with RA treated by golimumab were consecutively included. Ultrasound examination was performed at 52 synovial sites, bilateral first to fifth MCP, first IP and second to fifth PIP joints, first to fifth flexor tendon and wrists, 2nd and 6th compartment of extensor tendons and first to fifth MTP joints, by using HI VISION Ascendus (Hitachi Medical Corporation, Japan) with a multifrequency linear transducer (18–6 MHz). The GS and PD signals were scored in each synovial site using a semi-quantitative scale from 0 to 3.

Results Fifty-five patients with RA (46 female, mean age: 64.2±12.1 years) were included and analyzed. In comparison between the dose of Golimumab at the time of ultrasound examination, disease activity (DAS28-CRP) was significantly higher in 100mg group (100mg, n=15: 3.6±1.0, 50mg, n=40: 2.3±0.9; p<0.001), but ultrasound findings were not significantly different between golimumab 100mg and 50mg groups. In patients achieving remission, ultrasound findings were not different between 100mg started and 50mg started groups.

Conclusions Even patients have high disease activity, golimumab 100mg suppress the synovitis and tenosynovitis very well. In the condition where disease activity was sufficiently controlled, there was no difference in the synovitis findings of ultrasound at the dose of golimumab.

Acknowledgements We wish to thank Setsuko Takeda, Ayumi Hashimoto, Emi Yamashita, Rika Morinaka, Hatsue Ueda and Tomomi Iwahashi for their special efforts as a sonographer and collecting data.

Disclosure of Interest None declared