Efficacy and safety of Bujing Yishi tablet for glaucoma with controlled IOP: study protocol for a multi-centre randomized controlled trial

BACKGROUND: As an irreversible, intractable disease with vision loss, glaucoma leads to permanent and progressive damage of visual function. Lowering high intraocular pressure (HIOP) is the first choice for treating glaucoma; however, the control of HIOP is not enough to prevent progressive vison loss. Currently, the therapies to treat glaucoma with controlled IOP (GPCI) are unsatisfactory. Chinese medicine is effective for improving visual function in patients with GPCI. Bujing Yishi tablets (BJYSP) have been the standard preparation for treating GPCI in our hospital for decades. However, no rigorous randomized controlled clinical studies have investigated its effects and safety. METHODS: This study will be a 6-month, multicenter, stratified trial following a prospective, randomized, open-label, blinded endpoint (PROBE) protocol. A total of 216 eligible GPCI patients aged 18–75 years will be stratified according to the early, moderate, and advanced stages of glaucoma. After stratifying, the participants will be randomly assigned to the BJYSP group or control group at a ratio of 1:1. Following randomization, participants in the BJYSP group and control group will receive BJYSP and mecobalamin tablets, respectively, for the same 6-month period. The primary outcomes will include the best-corrected visual acuity (BCVA), visual field assessment, visual evoked potential (VEP) test, and Heidelberg retina tomography II (HRT II); the secondary outcomes will include intraocular pressure (IOP) and Traditional Chinese medicine (TCM) clinical symptom scales. The primary and secondary outcomes will be measured at baseline and 8, 16, and 24 weeks thereafter. Safety assessments will also be evaluated at baseline and 12 and 24 weeks thereafter. DISCUSSION: This study will be a standardized, scientific, clinical trial designed to evaluate the therapeutic effects and safety of BJYSP as a novel therapeutic strategy for improving visual function in patients with GPCI. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR1800016431. Registered on 1 June 2018.