Clinical Research Directory

Inclusion Criteria: * Male or female subjects aged 18-75 years (inclusive) * Chronic plaque psoriasis (PSO) for at least 6 months prior to the randomization. * Psoriasis Area Severity Index (PASI) \>=12 and body surface area (BSA) affected by PSO \>=10% and Static Physician Global Assessment (sPGA) score \>=3. * Subjects who are suitable for systemic treatment or phototherapy for psoriasis as judged by the investigator * Subjects who are able to use effective contraception from the screening period to 6 months after the last dose Exclusion Criteria: * Forms of psoriasis other than chronic plaque-type (e.g., pustular, erythrodermic and/or guttate psoriasis) at screening or baseline Drug-induced psoriasis * Ongoing use of prohibited treatments * Any active infection (other than common cold) within 14 days * Serious infection defined as requiring hospitalization or iv anti-infective(s) within 1 month prior to randomization * Have previously received any drug that directly targets IL-17 or IL-17 receptor * Have concurrent or recent use of any biologic agent within the following washout periods: etanercept \<28 days; infliximab and adalimumab \<60 days; golimumab \< 90 days; anti-IL-12/anti-IL-23 or anti-IL-23p19 antibody drugs \<6 months; or other anti-psoriatic therapy not listed herein within its 5 half-lives prior to randomization * A history of inflammatory bowel disease or other serious autoimmune disease * Previously diagnosed with serious mental illness such as anxiety, depression or suicidal tendency