Mingjing granule, a traditional Chinese medicine in the treatment of neovascular age-related macular degeneration: study protocol for a randomized controlled trial

BACKGROUND: Neovascular age-related macular degeneration (nAMD) is the most common cause of irreversible vision loss and blindness among the older people aged 50 and over. Although anti-vascular endothelial growth factor (anti-VEGF) therapies have resulted in improving patient outcomes, there are limitations associated with these treatments. In China, traditional Chinese medicine (TCM) has been used to treat eye diseases for more than 2000 years. Previous studies have shown that TCM may be beneficial for nAMD patients. However, explicit evidence has not been obtained. The purpose of the present trial is to examine the efficacy and safety of the Mingjing granule, a compound Chinese herbal medicine, for nAMD patients. METHODS/DESIGN: This is a double-blind, placebo-controlled, randomized trial of Mingjing granule as an add-on to intravitreous ranibizumab for nAMD. One hundred eighty nAMD patients from six hospitals in China will be enrolled according to the inclusion and exclusion criteria and randomly allocated into two groups, 90 in each. All participants will receive a 24-week treatment and then be followed up for another 24 weeks. The primary outcome is the mean change of best-corrected visual acuity at week 24 and 48 as compared to the baseline. The secondary outcomes include mean change in central retinal thickness, area of retinal hemorrhage and exudation, and TCM syndrome score, mean number of intravitreal ranibizumab injection, and total cost of the treatment. Indexes of safety include blood regular test, urine regular test, liver function test, renal function test, and electrocardiogram from baseline to weeks 24 and 48. Qualitative control and some standard operating processes will be formed throughout the trial. Any ocular or systemic adverse events will be treated suitably, and related data will be recorded accurately and completely in the case report form. DISCUSSION: Based on previous empirical and animal laboratory studies, this study will address the question of whether Mingjing granule could contribute to improving efficacy, safety, and efficiency with need for fewer intravitreal injections of anti-VEGF, improving compliance and visual outcomes in the management of persons with nAMD. TRIAL REGISTRATION: Chinese Clinical Trial Registry (http://www.chictr.org.cn), ChiCTR2000035990. Registered on 21 August 2020. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13063-021-05025-x.