Efficacy of tofacitinib, an oral janus kinase inhibitor, on clinical signs of moderate-to-severe plaque psoriasis in different body regions.

INTRODUCTION: Tofacitinib is a novel, oral Janus kinase inhibitor currently under investigation for plaque psoriasis. METHODS: This exploratory analysis of a Phase IIb, 12-week, dose-ranging study (clinicaltrials.gov identifier: NCT00678210) evaluated tofacitinib efficacy in four body regions of patients with moderate-to-severe chronic plaque psoriasis. Patients (n=197) were randomized to tofacitinib 2, 5, or 15 mg, or placebo, twice daily (BID). Psoriasis Area and Severity Index (PASI) score, body surface area values and change from baseline to week 12 were measured according to body region (head/neck, upper limbs, trunk and lower limbs). Change in Target Plaque Severity Score (TPSS) from baseline to week 12 was measured according to typically responsive as well as non-responsive treatment areas. RESULTS: At week 12, mean improvements in PASI and body surface area values were significantly greater with tofacitinib doses vs placebo across all four body regions measured (P<0.0001). TPSS in responsive areas decreased (improved) with tofacitinib 2, 5, and 15 mg BID vs placebo: -4.35, -4.79 and -6.32, vs -2.06, respectively (P<0.0001). In non-responsive areas, TPSS decreased with tofacitinib 2, 5, and 15 mg BID vs placebo: -3.74, -4.60 and -6.15, vs -2.23, respectively (P<0.01). CONCLUSION: Short-term (12-week) treatment with oral tofacitinib produced clinical improvement across all body regions assessed in patients with moderate-to-severe plaque psoriasis, including areas typically non-responsive to treatment.