This is a multicenter, randomized, double-blind, placebo-controlled Phase II clinical trial designed to assess the efficacy, safety, and tolerability of LW402 tablets in participants with non-segmental vitiligo.

Drawing on the prior/preclinical data of LW402 tablets, this clinical trial will incorporate three dose groups: 50 mg twice daily (BID), 100 mg BID, and 150 mg BID. The trial will be structured into a screening period (maximum 5 weeks), a treatment period (52 weeks, encompassing a 24-week main trial phase and a 28-week extension phase), and a safety follow-up period (4 weeks). The maximum duration of participation in this study will be 61 weeks.

Following the completion of 24-week data collection for all trial participants, unblinding will be performed in accordance with the pre-specified procedure. Subsequently, based on the unblinded data results, regulatory communication will be conducted with the Center for Drug Evaluation (CDE) regarding the initiation of the Phase III confirmatory clinical trial. Participants who have undergone unblinding will continue to attend scheduled study visits to complete the trial.

This is a multicenter, randomized, double-blind, placebo-controlled Phase II clinical trial designed to assess the efficacy, safety, and tolerability of LW402 tablets in participants with non-segmental vitiligo.

Drawing on the prior/preclinical data of LW402 tablets, this clinical trial will incorporate three dose groups: 50 mg twice daily (BID), 100 mg BID, and 150 mg BID. The trial will be structured into a screening period (maximum 5 weeks), a treatment period (52 weeks, encompassing a 24-week main trial phase and a 28-week extension phase), and a safety follow-up period (4 weeks). The maximum duration of participation in this study will be 61 weeks.

Following the completion of 24-week data collection for all trial participants, unblinding will be performed in accordance with the pre-specified procedure. Subsequently, based on the unblinded data results, regulatory communication will be conducted with the Center for Drug Evaluation (CDE) regarding the initiation of the Phase III confirmatory clinical trial. Participants who have undergone unblinding will continue to attend scheduled study visits to complete the trial.

Eligible trial participants will be stratified by disease severity (T-VASI < 15 vs. ≥ 15) and randomly allocated in a 1:1:1:1 ratio to three active treatment groups (50 mg BID, 100 mg BID, and 150 mg BID) and one placebo group. The planned sample size is 45 participants per group, with a total of 180 participants expected to be enrolled. Following 24 weeks of continuous dosing, participants in the placebo group will be re-randomized in a 1:1:1 ratio to the 50 mg BID, 100 mg BID, and 150 mg BID treatment groups for continued dosing until Week 52.

Inclusion Criteria:

• Aged 18 to 75 years (inclusive), with no restriction on gender;
• Clinically diagnosed with non-segmental vitiligo at screening;
• At the screening visit and baseline visit, the Facial Vitiligo Area Scoring Index (F-VASI) is ≥ 0.5 and the Total Vitiligo Area Scoring Index (T-VASI) is ≥ 3;
• At the screening visit and baseline visit, the disease is in the progressive stage or stable stage;

Exclusion Criteria:

• Individuals with a known allergy to Janus kinase inhibitors；
• Segmental vitiligo, mixed vitiligo, or undetermined vitiligo；
• White hair is present in more than 33% of facial skin lesions due to vitiligo, or in more than 33% of total skin lesions due to vitiligo;
• Skin lesions due to vitiligo are restricted to hairless areas, or hairless regions account for ≥30% of the lesion sites (e.g., lips, palms, fingers, labia);
• Individuals with other active hypopigmentary conditions during the screening period (including but not limited to Vogt-Koyanagi-Harada syndrome, hypopigmentation associated with malignant tumors [melanoma and mycosis fungoides], post-inflammatory hypopigmentation, pityriasis alba [a mild manifestation of atopic dermatitis], senile leukoderma [age-related depigmentation], chemical/drug-induced leukoderma, ataxia-telangiectasia, tuberous sclerosis complex, melasma, and congenital hypopigmentary disorders [including piebaldism, Waardenburg syndrome, hypomelanosis of Ito, incontinentia pigmenti, hereditary symmetrical dyschromatosis, xeroderma pigmentosum, and nevus depigmentosus]) are excluded. Note: Coexisting halo nevus (also referred to as Sutton nevus) is permitted;