Abstract
JS005 is a novel anti-IL-17A monoclonal antibody. A Phase Ia study (Study 1) in healthy adults, followed by a Phase Ib/II study (Study 2) in patients with moderate to severe plaque psoriasis (PsO), were designed to evaluate the safety, efficacy, and pharmacokinetic characteristics of JS005. Study 1 was a double-blind, randomized, placebo-controlled, single dose-escalation (15, 60, 150, 300, and 600 mg) study. Forty healthy participants were enrolled. Study 2 consisted of a dose-escalation (60, 150, 300, or 600 mg) phase Ib, and a multicentre, double-blind, placebo-controlled phase II administering JS005 150, 300 mg, or placebo once weekly from week 0 to 4 and once every 4 weeks from week 5 to 12. Forty and 143 patients were enrolled in phases Ib and II, respectively. The exposure of JS005 increased linearly with dosage, while the treatment-emergent adverse events did not show this trend. JS005 was well tolerated in both populations. In phase II of Study 2, the proportion of patients with at least a 75% improvement in the Psoriasis Area and Severity Index at week 12 was significantly higher in each JS005 group than in the placebo group (p < 0.001 for all comparisons). JS005 was highly effective in PsO patients.