Effectiveness of Modified Buzhong Yiqi Decoction In Treating Myasthenia Gravis: Study Protocol For A Series Of N-of-1 Trials
Abstract Background: Myasthenia gravis (MG) is an acquired autoimmune disease with high heterogeneity. The disease is chronic, relapsing repeatedly and progressive with acute exacerbation occasionally. Although the treatment of MG has developed, it is still unsatisfactory and has some unexpected side effects. Traditional Chinese medicine(TCM) has shown great potential in MG treatment, including relief of muscle weakness syndrome, improvement of patient’s quality of life and reduction of side effects of western medicine. The purpose of this study is to evaluate the effectiveness of Modified Buzhong Yiqi Decoction (MBYD) as an add-on therapy for MG through a small series of N-of-1 trials.Methods: Single-centre, randomized, double-blind, 3 crossover N-of-1 trials will be conducted to enroll 12 adult patients with MG diagnosed as spleen-stomach deficiency syndrome or spleen-kidney deficiency syndrome in TCM. Each N-of-1 trial has 3 cycles of two 4-week periods containing the MBYD period and placebo period. The wash-out interval of 1-week is prior to switching each period. Primary outcome: Quantitative Myasthenia Gravis (QMG). Secondary outcomes: the following scales: myasthenia gravis composite (MGC), myasthenia gravis activities of daily living profile (MG-ADL), myasthenia gravis quality of life (MG-QOL); the level of CD4+FoxP3+Treg cells and cytokines (IL-4, IL-17A, INF-γ, TGF-β) in the peripheral blood; the alterations of the composition of gut microbiota; reduction of the side effects of western medicine. Discussion: Paired t tests or Wilcoxon signed rank tests will be used to analyse this trials’ data and the results we arrived at will be interpreted cautiously. We assumed that this study would reveal that MBYD is effective for MG and provide robust evidence of the efficacy of TCM to treat MG. Trial registration: Chinese Clinical Trial Register, ID: ChiCTR2000040477, registration on 29 November 2020, http://www.chictr.org.cn/showprojen.aspx?proj=64688.