Efficacy and safety of Shenyankangfu tablets for primary glomerulonephritis: study protocol for a randomized controlled trial

BACKGROUND: Chronic kidney disease is a common disease. Most chronic kidney diseases evolve from primary glomerulonephritis. Proteinuria is an independent risk factor for the progression of chronic kidney disease. The general consensus is that therapy administered to decrease proteinuria should include steroids and/or immunosuppressants, angiotensin-converting enzyme inhibitors, and angiotensin II receptor blockers. However, the side effects of, and adverse reactions to, these agents reduce the benefits to patients. In addition, the cost of these drugs is relatively high. Therefore, identification of inexpensive and effective drugs to decrease proteinuria is urgently needed. Shenyankangfu tablets have been a widely applied Chinese patent medicine for many years to decrease proteinuria. However, there is a lack of research-derived data regarding the clinical use. Therefore, we designed the present randomized controlled clinical trial to compare the efficacy and safety of Shenyankangfu tablets versus losartan potassium for control of proteinuria in patients with primary glomerulonephritis. METHODS/DESIGN: This study will be a multicenter, prospective, double-blind, double-dummy, randomized controlled clinical trial. We will enroll 720 patients diagnosed with primary glomerulonephritis. The eligible patients will be randomly divided into the following groups at a 1:1:1:1:1 ratio: Shenyankangfu tablets group, losartan potassium 50 mg group, losartan potassium 100 mg group, Shenyankangfu tablets + losartan potassium 50 mg group, and Shenyankangfu tablets + losartan potassium 100 mg group. All groups will be followed up for 48 weeks; follow-up visits will be performed, at weeks 0, 4, 8, 12, 24, 36, and 48. The primary efficacy outcome will be the post-treatment change in the 24-hour proteinuria level, and the secondary efficacy outcomes will be the post-treatment changes in the serum creatinine level, estimated glomerular filtration rate, traditional Chinese medicine syndrome score, and serum albumin level. DISCUSSION: The results of this trial will provide solid data for use in evidence-based medicine with respect to the efficacy and safety of Shenyankangfu tablets for control of proteinuria in patients with primary glomerulonephritis compared to those of losartan potassium. Moreover, we infer that therapy comprising Shenyankangfu tablets + losartan potassium can decrease proteinuria to a larger extent than Shenyankangfu tablets or losartan potassium can alone. TRIAL REGISTRATION: This trial was registered on 12 February 2014 at ClinicalTrials.gov (ID number NCT02063100). ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1745-6215-15-479) contains supplementary material, which is available to authorized users.