Clinical Dose-Response of Inflammation Formula Number 1 Granules Versus Traditional Decoction in the Treatment of Patients With Mild to Moderate Atopic Dermatitis: Protocol for a Multicenter Randomized Controlled Trial.

Background: Atopic dermatitis (AD) is a common inflammatory skin disease associated with substantial disease burden. Traditional Chinese medicine (TCM) has shown beneficial effects in improving AD symptoms and reducing recurrence. Inflammation Formula Number 1 (IFN-1), a TCM prescription consisting of 10 herbal ingredients, has demonstrated favorable efficacy in clinical practice. However, traditional decoction preparation is time-consuming and inconvenient for long-term standardized use. Granule formulations may improve convenience, stability, and quality control, but their dose-response relationship and equivalence to traditional decoction remain unclear. Objective: This multicenter, prospective, randomized equivalence trial aims to evaluate the efficacy, safety, and dose-response relationship of IFN-1 granule formulations compared with traditional decoction in patients with mild to moderate AD. Methods: A total of 300 patients with mild to moderate AD aged 18 to 60 years will be recruited from 5 hospitals between April 2026 and January 2027. Participants will be randomly assigned in a 2:2:1:1 ratio to the traditional decoction group (n=100, 33.3%), standard-dose granule group (n=100, 33.3%), two-thirds dose granule group (n=50, 16.7%), or one-tenth dose granule group (n=50, 16.7%). All groups will receive 4 weeks of treatment. The primary end point is the proportion of patients achieving at least 50% improvement in the Eczema Area and Severity Index (EASI) at week 4. Secondary outcomes include EASI75, EASI90, Investigator Global Assessment score of 0 or 1, body surface area involvement, Dermatology Life Quality Index, pruritus numerical rating scale, Patient-Oriented Eczema Measure, and TCM syndrome scores. Outcomes will be assessed at baseline and weeks 1, 2, and 4. Statistical analyses will be conducted using SAS (version 9.4). Equivalence will be evaluated using a 2-sided 95% CI approach with a predefined equivalence margin of -15% to +15%. Results: Funding for this study was obtained in 2025. Ethical approval was granted by the Ethics Committee of Shanghai Skin Disease Hospital in December 2025, and the trial was registered with the International Traditional Medicine Clinical Trial Registry (ITMCTR2026000452). Participant recruitment is scheduled to begin in April 2026 and continue through January 2027. No patients were recruited at the time of manuscript submission. Data analysis is expected to commence in March 2027, and the primary study findings are anticipated to be published in 2028. Conclusions: This trial will determine whether IFN-1 granules achieve efficacy comparable to traditional decoction while improving treatment convenience. The findings may provide evidence for dose optimization and standardized clinical application of TCM granule formulations in AD management.