This clinical study aims to compare the safety and effectiveness of two treatments-oral Tacrolimus capsules and Dexamethasone micro-pulse therapy-in children aged 4-12 years with rapidly progressing vitiligo. The study is a multicenter, randomized, controlled trial involving 90 participants, who will be divided equally into two groups. One group will receive daily Tacrolimus, while the other will take Dexamethasone on weekends. Over 24 weeks, doctors will monitor improvements in skin repigmentation, side effects, and overall health through regular check-ups and blood tests. The goal is to determine which treatment better controls disease progression and improves quality of life for children with vitiligo.

Key Points:

• For children with rapidly spreading vitiligo.
• Compares two common medications.
• Follows participants for 6 months.
• Focuses on safety and effectiveness.

Background:

Vitiligo is an autoimmune skin condition causing pigment loss, significantly impacting children's well-being. Current treatments like systemic corticosteroids (e.g., Dexamethasone) carry risks of long-term side effects. Tacrolimus, an immunosuppressant with a safer profile in other pediatric conditions, shows promise but lacks evidence for oral use in vitiligo. This trial addresses this gap by comparing Tacrolimus and Dexamethasone.

Study Design:

• Multicenter, randomized, controlled trial across 5 hospitals in China.
• 90 participants (4-12 years) with rapidly progressing non-segmental vitiligo (VIDA score 4).
• Interventions:
• Tacrolimus group: 0.1±0.05 mg/kg/day, divided into two doses.
• Dexamethasone group: 0.05±0.025 mg/kg/weekend pulse dosing.
• Duration: 24 weeks with follow-ups at 4, 8, 12, 16, 20, and 24 weeks.

Outcome Measures:

• Primary: Proportion achieving ≥50% improvement in Vitiligo Area Scoring Index (VASI 50) at 24 weeks.
• Secondary: VASI 75/90 response rates, Investigator Global Assessment (IGA) scores, and safety parameters (blood tests, metabolic panels, adverse events).

Statistical Analysis:

Data will be analyzed using chi-square tests to compare efficacy and safety between groups (significance: p ≤ 0.05). All analyses adhere to intention-to-treat principles.

Ethics & Compliance:

Approved by the Ethics Committee of the First Affiliated Hospital of Air Force Medical University. Informed consent is obtained from all participants' guardians.

Inclusion Criteria:

• Children aged 4-12 years diagnosed with rapidly progressive non-segmental vitiligo (VIDA score ≥4, indicating disease progression within the past 6 weeks).

Total body surface area (BSA) affected by vitiligo between 1% and 50%. Guardians provide written informed consent for the child's participation.

Exclusion Criteria:

• Stable-phase childhood vitiligo. Segmental, mucosal, undetermined, or generalized vitiligo. Systemic immunosuppressive therapy within the past 4 weeks. Known hypersensitivity to tacrolimus, other macrolide drugs, or study drug excipients.

Comorbidities precluding oral tacrolimus use (e.g., severe hepatic/renal dysfunction).

Obesity or systemic diseases (e.g., tuberculosis, acute/chronic infections, hypertension, congenital cardiovascular disease).

Any condition deemed by investigators to increase participant risk or interfere with trial execution.