LAUSR

Background Axial involvement in early psoriatic arthritis (ePsA) patients (pts) is often poorly diagnosed. Magnetic resonance imaging (MRI) of sacroiliac joints (SIJs) helps to better define spinal involvement and is used as an outcome measure to evaluate treatment of axial disease with TNF blockers. Treat-to-target (T2T) strategy was studied in various manifestations of PsA except axial involvement. Objectives to assess the effect of tight control T2T strategy on the 12-months dynamics of active MRI sacroiliitis (MRI-SI) in peripheral ePsA pts. Methods 89 treatment-naive pts (M/F–42 /47) with active peripheral ePsA, according to CASPAR criteria were included; mean age 36.5±10.9 yrs., disease duration 12.1±10.1 mo., disease activity index (DAS) 5.2±2.8, C-RP 16.1 [6.6; 31.0] mg/l, ESR 22.5±19.2 mm/h. At baseline and every 3 mo. of therapy all pts underwent standard clinical examination of PsA activity. All patients were evaluated for the presence of inflammatory back pain (IBP) by ASAS criteria. In pts having IBP, disease activity was also measured by BASDAI. At baseline MRI of SIJs was performed in 79 pts, both with and without IBP, on Signa Ovation 0.35T. Bone marrow edema (BME) on MRI (STIR), considered as active MRI sacroiliitis (MRI-SI), was evaluated by an independent reader. MRI of SIJs was repeated after 12 mo. in 20 pts who had completed a year of therapy having MRI-SI at baseline. Positive dynamics was indicated by the disappearance of BME on MRI (STIR). The main goal of T2T strategy was to reach remission or low/minimal disease activity (LDA/MDA). LDA was considered at DAS<1.6 or DAS28<2.6, remission was considered at DAS<1.6 or DAS28<2.6. At baseline all pts were treated with methotrexate (MTX) subcutaneous (s/c). The dose of MTX was escalated by 5 mg eow from 10 mg/wk to 20–25mg/wk. If the patient did not achieve LDA/MDA or remission after 3 mo. of MTX mono-therapy (MoT), combination therapy (CoT) with MTX+ adalimumab (ADA) 40 mg (s/c) eow was started. All pts were treated with NSAIDs: nimesulide 100–200mg or eterikokxib 60–90 mg per day. Results IBP was found in 58 out of 89 pts (65.1%). Disease activity by BASDAI in pts with IBP was 4.5±1.6. At baseline MRI-SI was observed in 28 out of 79 (35.4%) pts. Among the group of 20 pts who had completed a year of therapy having MRI-SI at baseline, 16 (80%) pts after 12 mo. of therapy demonstrated positive dynamics. Among these 16 pts, 8 (50%) pts underwent MoT and 8 (50%) pts underwent CoT. In the CoT-group pts received ADA for 6–9 mo. After 12 mo. of therapy, BME of SIJs on MRI still remained in 4 out of 20 (20%) pts. Among these 4 pts 2 pts underwent MoT and 2 pts underwent CoT (both pts received ADA for 3 mo., 9 th-12th mo. of therapy). Conclusions tight control T2T strategy in the Russian cohort of peripheral ePsA pts, demonstrated positive dynamics of active MRI-SI in 80% of pts after 12 months of therapy irrespective of the treatment used. These preliminary results demonstrate that tight control T2T strategy is effective not only in peripheral arthritis but also in axial involvement in ePsA. To confirm its effectiveness the strategy still needs to be verified on larger cohorts of pts. Disclosure of Interest None declared