SAT0322 The effect of guselkumab on dactylitis: results from a phase 2 study in patients with active psoriatic arthritis

Background In a Phase 2 study, Guselkumab (GUS) was shown to be safe and effective in patients (pts) w/active psoriatic arthritis (PsA). Objectives To evaluate the effect of GUS on dactylitis in a subset of pts w/dactylitis at baseline (BL) in the phase 2 PsA study of GUS. Methods Pts w/active PsA and ≥3% body surface area of plaque psoriasis, despite current or previous treatment, were randomised 2:1 to receive 100 mg subcutaneous GUS at wks 0, 4 then every 8 weeks (wks, q8w) or placebo (PBO) during a 24wk double-blind treatment period. At wk16, pts w/ Results Of 149 pts, 81 presented w/dactylitis at BL (PBO n=23, mean[SD]=3.9 [3.01]; GUS n=58, mean[SD]=6.5 [6.15]) and 66 continued to the active treatment period (PBO→GUS n=16; GUS→GUS n=50). The dactylitis subset was similar to the overall population in BL characteristics except for higher median values for # of swollen joints, # of tender joints, and CRP. At wks 16 and 24, the GUS group had a significantly greater reduction in the dactylitis score (wk24 mean [SD] change from BL, PBO: −0.4 [6.06]; GUS: −3.8 [4.93]; p=0.006) and a greater% of pts w/dactylitis resolution, compared to the PBO group (figure 1). Consistent results were obtained w/the # digits w/dactylitis (wk24 mean [SD] change from BL, PBO: −0.2 [3.04]; GUS: −2.1 [2.21]; p=0.003). Improvement in dactylitis seen at wk24 was maintained in the GUS→GUS group (wk56: mean[SD] change from BL=−5.5 [4.84], 75% of pts w/resolution) and the values for the PBO→GUS group (wk56: mean[SD] change from BL=−4.4 [3.50], 93.7% of pts w/resolution) approached those of the GUS→GUS group. Improvement in dactylitis was greater in ACR20/ACR50 responders vs non-responders in GUS-treated patients (Table 1) and was significantly correlated with improvement in TJC (R=0.38, p=0.004), SJC (R=0.50, p Conclusions GUS is efficacious in resolving symptoms of dactylitis in pts w/active PsA. This effect on dactylitis is correlated with improvement in joint symptoms and physical function. Disclosure of Interest D. Gladman Grant/research support from: Janssen Research and Development, LLC, W.-H. Boehncke Grant/research support from: Janssen Research and Development, LLC, A. Gottlieb Grant/research support from: Janssen Research and Development, LLC, P. Helliwell Grant/research support from: Janssen Research and Development, LLC, P. Nash Grant/research support from: Janssen Research and Development, LLC, X. Xu Employee of: Janssen Research and Development, LLC, S. Xu Employee of: Janssen Research and Development, LLC, Y. Wang Employee of: Janssen Research and Development, LLC, E. Hsia Employee of: Janssen Research and Development, LLC, C. Karyekar Employee of: Janssen Research and Development, LLC, A. Deodhar Grant/research support from: Janssen Research and Development, LLC