Phase II/III Study of FXS5626 in Participants With Non-segmental Vitiligo

Participants must meet all of the following inclusion criteria: 1. Understand the trial procedures and methods, voluntarily participate in this trial, be able to communicate well with the investigator, comply with the requirements of the entire study, and provide written informed consent; 2. Screening age must meet the following criteria: 1\) Age ≥18 years and ≤75 years, regardless sex (Phase 2); 2) Age ≥12 years and ≤75 years, regardless of sex (Phase 3); 3. At screening，participants must have a body mass index (BMI) ≥18 kg/m²; for adolescent participants in the Phase 3, baseline body weight must be ≥40 kg; 4. Clinically diagnosed with non-segmental vitiligo, either active or stable, with a disease history ≥3 months; 5. At the screening and baseline visits, vitiligo lesions must satisfy all of the following criteria: 1. The percentage of vitiligo lesion area relative to the total body surface area (BSA) is ≥3%, excluding involvement of the palms, dorsa of the hands (fingers), soles, and dorsa of the feet; 2. Facial involvement BSA (F-BSA) ≥0.5%; 3. T-VASI ≥0.5 and 3 ≤ T-VASI ≤50; 6. Participants must ensure and agree that, from 28 days before signing the informed consent form to 28 days after the last dose, female participants of childbearing potential, male participants, and their spouses will use effective contraceptive methods other than oral medications (such as condoms or intrauterine devices), and will not donate sperm or ova during this study. Exclusion Criteria 1. Presence of vitiligo-related medical conditions and other skin diseases at screening, as assessed by the investigator; 2. Presence of \>33% leukotrichia in areas of vitiligo on the face or \> 33% leukotrichia in areas of vitiligo on the body (including the face); 3. As assessed by the investigator, accompanied by active infection or history of infection; 4. Patients with a history of severe herpes simplex and herpes zoster infections, or with active/current herpes simplex or herpes zoster infection; 5. Participants with any other clinically significant medical history, or other conditions that, as assessed by the investigator, may affect the participant's safety or compliance, or result in the participant's inability to complete the study.