Efficacy and Safety of Runzaozhiyang Lotion for Chronic Hand Eczema: Protocol for a Randomized Controlled Trial.

Background: Chronic hand eczema (CHE) is a prevalent inflammatory skin disease in clinical practice. Guidelines recommend the use of topical medications, including corticosteroids and calcineurin inhibitors; however, prolonged use of these drugs may result in adverse effects, such as skin atrophy, drug tolerance, and rebound phenomena. Moreover, these medications exhibit limited efficacy in managing chronic hypertrophic hand eczema. Traditional Chinese medicine (TCM) has a long history of treating patients. The Runzaozhiyang lotion (RZZYL) is often used in the Department of Dermatology of Guang'anmen Hospital, China Academy of Chinese Medical Sciences, for these patients, with marked efficacy on symptoms, keratinization, hypertrophy, and pruritus improvements. Nonetheless, there is still no high-quality evidence from evidence-based medicine to prove the effectiveness and safety of CHE treatment.

Objective: This study aimed to examine the efficacy and safety of a classic Chinese herbal prescription, RZZYL, for CHE and to provide a different treatment option for patients with hand eczema who are resistant to conventional Western pharmaceutical treatments.

Methods: This study is a clinical trial characterized as randomized, double-blind, double-dummy, and positive drug-controlled. A total of 122 patients diagnosed with CHE have been randomized and allocated in a 1:1 ratio into 2 distinct groups, with one receiving the intervention and the other serving as the control. Participants in the intervention group will receive RZZYL granules along with a placebo cream of mometasone furoate, whereas the control group will get mometasone furoate cream in combination with a placebo for RZZYL granule. Both groups will be treated with either the active drug or a placebo for 4 weeks. The primary outcome metrics are the Hand Eczema Severity Index (HECSI) and the Numerical Rating Scales (NRS). Secondary outcome metrics consist of the target lesion area score, the Patient-Oriented Eczema Measure (POEM), the Dermatology Life Quality Index (DLQI), and the Investigator Global Assessment (IGA). The outcomes will be assessed at the start of the study and again at 2 and 4 weeks after the treatment period.

Results: The study will be conducted according to the guidelines and regulations approved by the participating institutions. Recruitment is expected to commence in March 2025 and conclude in March 2026. Data collection is anticipated to be completed by June 2026, with the study expected to conclude in August 2026.

Conclusions: This protocol addresses the limitations of previous research and aims to explore the efficacy and safety of RZZYL in treating CHE through a higher-quality clinical study. It seeks to provide additional treatment options for patients with CHE who are resistant to or have poor responses to current therapies.