A Study of QY101 Ointment in Subjects With Plaque Psoriasis

Inclusion Criteria:

1. Be able to understand and comply with the test process, voluntarily participate in thetest and provide informed consent;
2. When signing the informed consent, age ≤ 18 years old ≤ 75 years old, gender is notlimited;
3. The patient meets the diagnosis of plaque psoriasis, has a history of plaque psoriasisfor ≥ 6 months before randomization, and meets the following conditions:
4. At baseline, plaque psoriasis covered 2% to 20% of BSA (including both ends) (scalp, palms, and soles were not counted as BSA);
5. Physician overall assessment (PGA) ≥ 2 at baseline;
6. Fertile men and women of childbearing age must agree to use reliable contraceptionfrom the time they sign an informed consent until six months after the last dose ofthe investigational drug; Blood pregnancy tests for women of childbearing age must benegative during screening and at baseline.

Exclusion Criteria:

1. Other types of psoriasis were diagnosed during screening, such as gutting psoriasis,erythrodermic psoriasis, generalized pustular psoriasis, arthropathic psoriasis,drug-induced or drug-aggravated psoriasis;
2. The presence of other systemic autoimmune inflammatory diseases and skin lesions (suchas eczema), which may affect the evaluation of treatment outcomes;
3. Subjects who are expected to receive additional local therapy, phototherapy, or othersystemic therapy other than investigational medication during the trial;
4. Taking drugs that can aggravate psoriasis (such as lithium, antimalarial drugs, etc.);
5. Patients who have failed or are intolerant to previous treatment withPhosphodiesterase-4 (PDE4) inhibitors;
6. Known to be allergic to the study drug or related excipients (QY101 ointment andexcipients: albuvarin, light liquid paraffin, propylene glycol, Carbonic acid,glyceryl behenate, glyceryl monodistearate, hydroxyphenyl butyl, propyl gallate anddisodium edetate), or have a history of angioedema or allergy to topical drugs;
7. receive contraindicated drugs, supplements, and other treatments prescribed in thistrial that may affect the course of psoriasis within the specified time period priorto initial dosing or planned for the duration of the trial (see Appendix 2:Concomitant medications during the trial);
8. Participants who are participating in another interventional clinical trial or whoselast use of another investigational drug is less than 5 half-lives prior to the firstdosing of the investigational drug;
9. any history of infection or recurrent infection requiring systemic antibiotictreatment within 2 weeks prior to first dosing, or serious infection requiringhospitalization or intravenous antibiotic treatment within 8 weeks prior to firstdosing (e.g., pneumonia, cellulitis, bone or joint infection, etc.); Recurrent,chronic, or other active infection at the time of initial dosing, if the investigatordetermines that participation in the study increases participants' risk;
10. Use of a suppressant of CYP3A liver metabolic enzyme, or use of any medication,including prescription, over-the-counter, and herbal oral or topical drugs, other thanvitamins and/or Paracetamol, within 2 weeks prior to initial administration;
11. Participants who have received, or plan to receive, a live or attenuated vaccinewithin 4 weeks prior to initial administration;
12. Abnormal laboratory test results during screening, including:
13. Alanine aminotransferase (ALT), aspartate aminotransferase (AST) or basicphosphoric acid Enzyme (ALP) > 2.5 × Upper Limit of Normal (ULN);
14. Serum creatinine > 1.5×ULN, or creatinine clearance < 50 mL/min.
15. Hepatitis B surface antigen (HBsAg) positive or hepatitis B core antibody (HBcAb)positive, and hepatitis B virus deoxyribonucleic acid (HBV-DNA) positive; Or hepatitisC virus (HCV) antibody positive and HCV-RNA positive; Or positive for HIV, TreponemaPallidum-Antibody (TP-Ab) (Rapid Plasma Reagin, TP-AB) RPR] or Toluidine Red UnheatedSerum Test (except for negative Toluidine Red Unheated Serum Test, TRUST);
16. The presence of decompensated cardiac insufficiency (New York Heart Disease Assocation (NYHA) class III or IV) within 6 months prior to screening; History of unstable anginapectoris, myocardial infarction, coronary artery bypass grafting or coronary stentimplantation; There are severe arrhythmias that require medication or cardiacassistance, such as degree II type 2 or degree III atrioventricular block, long QTInterval, or long QT block. QT syndrome or Fridericia Corrected QT Interval (QTcF)abnormality (male > 470 ms female > 480 ms) corrected according to the Fridericiaformula and assessed by the investigator as unsuitable for participation in thisclinical trial; Hospitalization due to Cardiovascular (CV) events, CV disease or CVsurgery; Peripheral artery disease diagnosed by angiography with stroke (ischemic orhemorrhagic, including transient ischemic attack) should be excluded;
17. Known malignant tumors or history of malignant tumors (excluding clinically cured skinbasal cell carcinoma, skin squamous cell carcinoma, cervical carcinoma in situ);
18. Patients with psychoneuro-related diseases or history (such as depression, epilepsy),which affect medication compliance or the researcher's clinical judgment of suiciderisk;
19. Pregnant or lactating women, female subjects or male subjects' partners planning tobecome pregnant (within 6 months after signing the informed consent to the lastadministration of the study drug);
20. Other conditions deemed unsuitable for participation in this study by theinvestigator.