Efficacy of Tripterygium wilfordii granules in the treatment of plaque psoriasis: Protocol for a single-arm trial

Background: Tripterygium wilfordii is a traditional Chinese medicine renowned for its exceptional anti-inflammatory and immunomodulatory properties. Triptolide, the predominant compound found in T. wilfordii , has been extensively studied for its remarkable therapeutic effects in psoriasis treatment. However, the usage of triptolide is often hindered by uncontrollable adverse reactions, posing a considerable challenge. Consequently, it becomes imperative to effectively harness the benefits of triptolide while minimizing its drawbacks. In this study, we aimed to elucidate the molecular mechanism underlying the topical anti-inflammatory effects of triptolide, investigate the factors contributing to individual variations in response to triptolide, and identify potential markers for predicting the efficacy of triptolide in treating plaque psoriasis. Methods: This was a single-arm study. All patients with plaque psoriasis who met the inclusion criteria were to be treated with Tripterygium granules for 4 weeks and followed up for 12 weeks. The improvement rate of the Psoriasis Area and Severity Index (PASI) score was the main therapeutic index. The relationship between C-terminal binding protein 1 (CtBP1) protein expression in skin lesions and the therapeutic effect was evaluated. We evaluated secondary indicators, including body surface area (BSA), Physician Global Assessment (PGA), Dermatology Life Quality Index (DLQI), Visual Analog Scale (VAS), traditional Chinese medicine (TCM) syndrome score, relapse rate, and body surface area. Safety indicators included vital signs, routine blood tests, liver function, renal function, physical examination, adverse events and serious adverse events. Discussion: T. wilfordii granules are a frequently prescribed Chinese medicine for psoriasis treatment. However, the effectiveness of this medicine varies among patients, with some experiencing poor results. The level of serum CtBP1 expression differs between patients who respond positively to T. wilfordii granules and those who do not. Therefore, CtBP1 has the potential to serve as a crucial indicator in predicting the efficacy of T. wilfordii granule treatment of plaque psoriasis. Trial registration ChiCTR.govChiCTR2000036398. Registered on August 22, 2020.