A Prospective Study to Assess the Efficacy of IL-17 Inhibitors on Subclinical Enthesitis in Patients With Moderate to Severe Psoriasis Based on Power Doppler (PD) Ultrasonography (PDUS)

Inclusion Criteria: 1. Adult patients ( ≥ 18 years of age) with chronic plaque-type psoriasis 2. Meet one of the following conditions: Psoriasis Area and Severity Index \[PASI\] score \> 6, or scalp involvement, or nail involvement. 3. Inflammatory changes on ultrasound consistent with OMERACT definition at least at one peripheral attachment point at screening, defined as thickening and/or abnormal echogenicity of tendons or ligaments at the site of their insertion into the bone (within 2 mm of the talar cortex), and active Doppler signals that may indicate structural damage such as bone erosion, syndesmophytes/calcifications 4. Psoriasis is inadequately controlled by current topical therapy or phototherapy 5. Able to sign the informed consent Exclusion Criteria: 1. Diagnosis of PsA2 according to CASPAR 2. Any known rheumatic disease, positive rheumatoid factor/anti-citrullinated protein antibodies, prior treatment with anti-rheumatic drugs 3. Treatment with systemic corticosteroids within 12 weeks or 5 half-lives of screening 4. Obesity impeded ultrasound examination 5. Pregnant or lactating women or women with plan for conception 5 months before or after treatment 6. Participated in other clinical trials 7. Concurrent significant medical problems, including but not limited to the following: uncontrolled hypertension (systolic blood pressure ≥ 160 mmHg and/or diastolic blood pressure ≥ 95 mmHg), congestive heart failure (NYHA class III or IV), total white blood cell count \< 2500/μl, or platelets \< 100,000/μl or neutrophils \< 1500/μl or hemoglobin \< 8.5 g/dL at screening. 8. Any liver function abnormality: aspartate aminotransferase (AST) \> 2xULN, alanine aminotransferase (ALT) \> 2xULN, total bilirubin (TBIL) \> 2xULN 9. Abnormal renal function: serum creatinine \> 2.0 mg/dl 10. History of ongoing, chronic or recurrent infectious disease or evidence of tuberculosis infection, defined as a positive PPD skin test or Mycobacterium tuberculosis interferon-gamma release assay (IGRA) test. 11. Current or relevant history of human immunodeficiency virus (HIV), hepatitis B or hepatitis C infection. 12. History of lymphoproliferative disease, or any known malignancy, or history of malignancy of any organ system within the past 5 years 13. Unable or unwilling to undergo repeated venipuncture 14. History of alcohol or drug abuse or evidence of abuse within 6 months prior to baseline 15. History of hypersensitivity to any component of the study drug 16. Did not accept live vaccines within 4 weeks prior to enrollment, do not have plan of vaccination program during the study, and no live vaccines are planned \> 6 months after the last dose of the study (herpes zoster vaccine \> 12 months)