The purpose of this study is to evaluate the efficacy and safety of different doses of SYHX1901 tablets in the treatment of moderate to severe plaque psoriasis.
Subject must be diagnosed of chronic plaque psoriasis with no morphological changes or significant outbreaks of disease activity assessed by the investigator;
Subject must be a candidate for systemic treatment or phototherapy assessed by the investigator;
Body Surface Area (BSA) affected by plaque-type psoriasis ≥10% at screening and baseline;
PASI score of ≥10 and Static Physician's Global Assessment (sPGA) score ≥3 at screening and baseline; 4. Negative blood pregnancy results should be provided 7 days (inclusive) prior to randomization, and subjects and their partners should voluntarily take contraceptive measures considered effective by the investigator during the study period and for at least 28 days after the study; 5. Subjects must be volunteer and be able to complete study procedures and follow-up examinations.
Forms of psoriasis other than plaque psoriasis (Guttate psoriasis、erythrodermic psoriasis、Pustular psoriasis、Drug-induced psoriasis);
Previous or current autoimmune disease that may affect the clinical evaluation of psoriasis;
Other active skin conditions that may affect the clinical evaluation of psoriasis;
Active bacterial, viral, fungal, or other infection that requires medical intervention;