Add-on astragalus in type 2 diabetes and chronic kidney disease: A multi-center, assessor-blind, randomized controlled trial.

BACKGROUND: Diabetes leads to chronic kidney disease (CKD) and kidney failure, requiring dialysis or transplantation. Astragalus, a common herbal medicine and US pharmacopeia-registered food ingredient, is shown kidney protective by retrospective and preclinical data but with limited long-term prospective clinical evidence. This trial aimed to assess the effectiveness of astragalus on kidney function decline in macroalbuminuric diabetic CKD patients. METHODS: This randomized, assessor-blind, standard care-controlled, multi-center clinical trial randomly assigned 118 patients with estimated glomerular filtration rate (eGFR) of 30-90 ml/min/1.73m2 and urinary albumin-to-creatinine ratio (UACR) of 300-5000 mg/g from 7 public outpatient clinics and the community in Hong Kong between July 2018 and April 2022 to add-on oral astragalus granules (15 gs of raw herbs daily equivalent) or to continue standard care alone as control for 48 weeks. Primary outcomes were the slope of change of eGFR (used for sample size calculation) and UACR of the intention-to-treat population. Secondary outcomes included endpoint blood pressures, biochemistry, biomarkers, concomitant drug change and adverse events. (ClinicalTrials.gov: NCT03535935) RESULTS: During the 48-week period, the estimated difference in the slope of eGFR decline was 4.6 ml/min/1.73m2 per year (95 %CI: 1.5 to 7.6, p = 0.003) slower with astragalus. For UACR, the estimated inter-group proportional difference in the slope of change was insignificant (1.14, 95 %CI: 0.85 to 1.52, p = 0.392). 117 adverse events from 31 astragalus-treated patients and 41 standard care-controlled patients were documented. The 48-week endpoint systolic blood pressure was 7.9 mmHg lower (95 %CI: -12.9 to -2.8, p = 0.003) in the astragalus-treated patients. 113 (96 %) and 107 (91 %) patients had post-randomization and endpoint primary outcome measures, respectively. CONCLUSION: In patients with type 2 diabetes, stage 2 to 3 CKD and macroalbuminuria, add-on astragalus for 48 weeks further stabilized kidney function on top of standard care.

Efficacy, safety and response predictors of adjuvant astragalus for diabetic kidney disease (READY): study protocol of an add-on, assessor-blind, parallel, pragmatic randomised controlled trial.

INTRODUCTION: Diabetic kidney disease (DKD) is a prevalent and costly complication of diabetes with limited therapeutic options, being the leading cause of end-stage kidney disease in most developed regions. Recent big data studies showed that add-on Chinese medicine (CM) led to a reduced risk of end-stage kidney disease and mortality among patients with chronic kidney disease (CKD) and diabetes. Astragalus, commonly known as huang-qi, is the most prescribed CM or used dietary herb in China for diabetes and DKD. In vivo and in vitro studies showed that astragalus ameliorated podocyte apoptosis, foot process effacement, mesangial expansion, glomerulosclerosis and interstitial fibrosis. Nevertheless, the clinical effect of astragalus remains uncharacterised. This pragmatic clinical trial aims to evaluate the effectiveness of add-on astragalus in patients with type 2 diabetes, stage 2-3 CKD and macroalbuminuria, and to identify related response predictors. METHODS AND ANALYSIS: This is an add-on, assessor-blind, parallel, pragmatic randomised controlled clinical trial. 118 patients diagnosed with DKD will be recruited and randomised 1:1 to receive 48 weeks of add-on astragalus or standard medical care. Primary endpoints are the changes in estimated glomerular filtration rate and urine albumin-to-creatinine ratio between baseline and treatment endpoint. Secondary endpoints include adverse events, fasting blood glucose, glycated haemoglobin, lipids and other biomarkers. Adverse events are monitored through self-complete questionnaire and clinical visits. Outcomes will be analysed by regression models. Subgroup and sensitivity analyses will be conducted for different epidemiological subgroups and statistical analyses. Enrolment started in July 2018. ETHICS AND DISSEMINATION: This study was approved by the Institutional Review Board of the University of Hong Kong/Hospital Authority Hong Kong West/East/Kowloon Central clusters (UW 16-553/HKEC-2019-026/REC (KC/KE)-19-0049/ER-4). We will report the findings in medical journals and conferences. The dataset will be available on reasonable request. TRIAL REGISTRATION NUMBER: NCT03535935.