LAUSR

Psoriatic arthritis (PsA) is a heterogeneous disease with multiple manifestations and choosing among treatments can be a complex decision. Patients (pts) with axial involvement and pts having dactylitis are more likely to develop a severe disease (1, 2). Tofacitinib (TOFA), an oral Janus kinase inhibitor, showed efficacy in treating PsA pts with dactylitis (3). However, its efficacy in treating PsA pts with activesacroiliitis(SI) and dactylitis has not been studied.To study the effect of TOFA therapy in PsA pts having active SI on MRI (MRI-SI) and dactylitis.40 pts (M/F – 23/17) with active PsA fulfilling the CASPAR criteria were examined. Median (Me) age 41.0 [35.0; 50.0] yrs, Me PsA duration 6.0 [3.0; 10.0] yrs. A standard clinical examination of PsA activity was performed: Me tender joint count 19 [12; 24], swollen joint count 11 [8; 16], patient’s global disease activity measured by Visual Analogue Scale (VAS) 70 [50; 80], patient’s pain VAS 65 [50; 75], Me activity indexes: DAPSA 44.2 [37.8; 55.3], BASDAI 6.0 [4.2; 7.0], ASDAS 3.8 [2.8; 4.4]. CRP 21.3 [3.2; 72.3] mg/L, ESR 28 [12; 52] mm/h. Enthesitis was observed in 65.9% of pts with Me LEI index 1 [0; 1], dactylitis in 53.7% of pts, Me digits with dactylitis 1 [0; 2]. Apart from a standard clinical examination, MRI of sacroiliac joints (SIJs) was performed in all 40 pts using MRI scanner Siemens General Electric 1.5 TESLA. Bone marrow edema/osteitis on MRI (STIR) considered active MRI sacroiliitis (MRI-SI), was evaluated by 2 independent readers (radiologist and rheumatologist). TOFA was given in 5 mg tablets bds over a period of 6 months, after which 35 patients underwent SIJ MRI. Me [Q25; Q75], Pierson-χ2tests were performed. All p<0.05 were considered to indicate statistical significance.Prior to TOFA therapy, MRI-SI was detected in 14 of 40 (35.0%) pts. At the end of 6 months therapy, MRI-SI was detected in 4 of 35 (11.4%) pts: in 3 pts with baseline SI; 1 pt showed negative dynamics, that is, development of active SI (absent at baseline). The decrease in number of active MRI-SI pts is statistically significant (p=0.017; Pearson-χ2). Significant differences between baseline symptoms in patients with MRI-SI (n=14) and without it (n=26) were definedby number of digits with dactylitis:2 [0; 4] and 0 [0; 2] (p=0.047),by ESR: 47 [26; 76] and 20 [6; 37] mm/h (p=0.025), and byWPAI overall work impairment due to health index:80 [60; 84]% and 20 [0; 60]% (р=0.033), respectively; these parameters were higher in MRI-SI subgroup. After 6 months of therapy number of digits with dactylitis, ESR and WPAI indexes were significantly lower as compared with the baseline ones (Table 1).After 6 months of TOFA therapy, no differences were found between groups of pts with and without MRI-SI in the number of digits with dactylitis (p=0.47), in ESR (p=0.79) and in WPAI (p=0.93).In PsA pts significant association of active MRI-SI was found with dactylitis, high ESR level and WPAI. Use of TOFA in pts with both active MRI-SI and dactylitis demonstrated its high efficacy in reduction of SI inflammation and dactylitis; it also significantly improved pts’ work productivity. These findings are important for personalized approach to treatment of PsA.[1]Brockbank JE et al. Ann Rheum Dis. 2005;64(2):188-90[2]Mease PJ et al. J Rheumatol 2018;45:1389-96[3]Gladman DD et al. N Engl J Med 2017;377:1525-36ELENA GUBAR: None declared, Tatiana Korotaeva Grant/research support from: Pfizer, Consultant of: Abbvie, BIOCAD, Bristol-Myers Squibb, Celgene, Eli Lilly, Janssen, Merck Sharp & Dohme, Novartis, Novartis-Sandoz, Pfizer, UCB, Speakers bureau: Abbvie, BIOCAD, Bristol-Myers Squibb, Celgene, Eli Lilly, Janssen, Merck Sharp & Dohme, Novartis, Novartis-Sandoz, Pfizer, UCB, Yulia Korsakova: None declared, Elena Loginova Speakers bureau: Janssen, Svetlana Glukhova: None declared, Polina Karpova: None declared