This study was designed as a double-blind, randomized, three-group-parallel, placebo-controlled clinical trial. One hundred and twenty patients with IgA nephropathy will be recruited, and the overall study design will be divided into two phases. In the pre-randomization phase, all participants will be confirmed to have received at least 3 months of RAAS blockers therapy and to have blood pressure within 130/80 mmHg before entering the next phase. After qualification confirmation and informed consent, the enrolled patients entered the post-randomization intervention phase. All participants were randomly divided into ART 100mg group, ART 50mg group, and placebo group, for 6 months of intervention. The flow diagram of the study progress is shown in Fig. 1. Each participant will be assigned eight visits, including 3 months before the randomization (visit 1), 2 months before the randomization (visit 2), 1 month before the randomization (visit 3), randomization (visit 4), 1 month after the intervention (Visit 5), 2 months after the intervention (visit 6), 3 months after the intervention (visit 7), and 6 months after the intervention (Visit 8). The schedule for enrollment, intervention, and assessment is shown in Table 1. The primary outcome measures will be determined by the change in proteinuria in the three groups after 6 months of intervention. The secondary outcome measures will be the changes in urinary protein creatinine ratio and estimated glomerular filtration rate (eGFR) from baseline after 1,3༌6 months of intervention, and the change in serum galactose-deficient IgA1 (Gd-IgA1) and Anti- Gd-IgA1 levels in patients will also be observed. We will stratify progression risk in IgA patients and retrospectively evaluate the effect of ART on proteinuria levels in IgA patients with different progression risks. The safety assessment of ART will be carried out throughout the study. The study protocol has been approved by the Ethics Committee of Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine (Number: DZMEC-KY-2020-30) and registered in the Chinese Clinical Trial Registry (ChiCTR) (Number: ChiCTR2000038104).
Schedule of recruitment, interventions, and assessments.
|a Items include: Urea, Creatinine, Total bilirubin, Serum glutamic pyruvic transaminase, Serum glutamic-oxaloacetic transaminase, Alkaline phosphatase, Sodium, Potassium, Calcium, Phosphorus, Total protein, Albumin, Uric acid.|
|b Items include: Urea, Creatinine, Sodium, Potassium.|
|c Items include: Gd-IgA1, Anti-Gd-IgA1(IgG/IgA).|
|Abbreviation: HCG, human chorionic gonadotropin.|
This protocol is reported according to the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) 2013 statement . The SPIRIT checklist is listed in Supplement Table 1.
Inclusion criteria for this study include:1) Ages 18–75; 2) Primary IgA nephropathy confirmed by renal biopsy; 3) Persistent proteinuria ≥ 1.0g/day after receiving adequate RAAS blockers treatment (proteinuria ≥ 1.0g/day both in visit 1 and visit 3); 4) eGFR ≥ 30 ml/min per 1.73m2 calculated by Chronic Kidney Disease Epidemiology Collaboration (CKD- EPI) equation.
Exclusion criteria included: Patients who had to be treated with corticosteroid immunotherapy (microplastic nephropathy with IgA deposition and the presence of crescents in more than 50% of the glomeruli of renal biopsy within 12 months); Patients who must be treated with other immunosuppressants (such as calcineurin inhibitors, cyclophosphamide or mycophenolate mofetil); Patients receiving systemic immunosuppressive therapy in the past 6 months; Patients with uncontrolled hypertension(systolic blood pressure > 160 mmHg or diastolic blood pressure > 110 mmHg); Secondary IgA nephropathy; Acute kidney injury; Malignant tumors; Patients with serious diseases of other systems (such as liver damage, heart damage, diseases of the blood system, systemic infections, digestive ulcers); Women who are planning or having pregnant; Patients with cognitive impairment who cannot sign the informed consent.
The subjects who no longer meet the inclusion criteria, have poor compliance, need immunosuppressive therapy, or have any other reason for the violation of the protocol will be determined by the investigators. These patients will be required to continue regular study visits as scheduled in the protocol after discontinuation of treatment.
Patients who refuse to participate in the study visits for personal reasons, or the researchers were unable to contact through all available means will be regarded as a dropout.
Patients had a severe liver or kidney damage during the trial (ALT or AST exceeding twice the normal upper limit, acute kidney injury); Severe clinical discomfort caused by the drug (such as severe nausea and vomiting, severe dizziness, and headache); Severe drug allergies. All criteria and decisions will be jointly determined by two or more physicians with the title of deputy chief or higher
Randomization and allocation
Eligible patients will be randomly divided into ART 100mg group, ART 50mg group, or placebo group at a ratio of 1:1:1. Random Numbers will be generated and sorted by independent statisticians using the SAS 9.4 (SAS Institute Inc), and then patients will be divided into three groups based on the remainder of the number divided by 3. The randomized numbers, rank order, and grouping will be stored in opaque envelopes with serial numbers, which will be kept by independent designers and statisticians throughout the study. The envelopes and study drug will be provided to enrolled patients separately by independent blind researchers.
In this study, a double-blind approach will be applied to patients and physicians. ART and placebo were placed in packaged capsules and distributed to patients by independent researchers. At the end of the study, professional independent statisticians unblind for the first time and performed a preliminary analysis of three sets of outcome data. The designer will then perform a second unblinding to confirm the group and the effect. If serious adverse events occur during the study period, patients will be treated with emergency blinding and relevant treatment according to the situation.
ART 100mg group oral 50mg ART tablets twice a day, ART 50mg group oral 25mg ART tablets twice a day, and placebo group oral equivalent placebo twice a day. ART tablets and placebo are provided by Guilin Nanyao Co. LTD. All patients will receive standard support treatment for IgA nephropathy including adequate RAAS blockers and blood pressure control. Permissible combination antihypertensive medications include diuretics, calcium channel blockers, andβ-receptor blockers. Hydrochlorothiazide or loop diuretics could be used when the antihypertensive targets are difficult to achieve. Statins and aspirins are also allowed when necessary. Prohibited drugs include proprietary Chinese drugs that may reduce proteinuria (such as Tripterygium wilfordii, Penicillium notatum, Huangkui capsules, Nephritis Rehabilitation tablets, Haikun Shenxi capsules), corticosteroids, and any immunosuppressants (such as mycophenolate mofetil, cyclophosphamide, azathioprine, HCQ).
The primary outcome was defined as the change in 24-hour urinary protein quantity and percentage change of proteinuria in all three groups after 6 months of intervention. Secondary outcomes included the changes in urinary protein creatinine ratio (UPCR), eGFR, and serum Gb-IgA levels in all three groups from baseline. The clinical characteristics of the patients were collected at baseline before enrollment, including age, gender, age, course of the disease, combined disease, medication history, and so on. Throughout the follow-up, patients will be asked to take urine and blood samples, which will be performed independently at each center.
The safety assessment includes any serious adverse event and a general adverse event according to the WHO acute and subacute side effects of the performance and indexing criteria for assessment. Patients' vital signs and any clinical discomfort will be monitored throughout the study period.
Data collection and management
The entire data collection and preliminary evaluation of the results were done by an independent third party. The data is collected in the form of a case report form (CRF), and then reviewed and stored by the lead researcher in each center. Two researchers will independently convert the original data into electronic storage data to ensure the accuracy of the data. All relevant documentation will be retained so that safety and key efficacy outcomes can be retrospectively evaluated in the future.
This is a double-blind, randomized, three-group-parallel, placebo-controlled clinical study, and sample size estimates were based on the change in proteinuria levels. According to the same kind of drugs (HCQ) in the treatment of IgA nephropathy study results, the average baseline proteinuria was 2.0 ± 0.8 g/day, and 36 participants of each arm will provide 90% of the detection ability, and assuming that the placebo group level of proteinuria has not changed, and ART treatment detect a 25% reduction in proteinuria (ART group: 0.5 ± 0.5 g/d, the control group 0.2 ± 0.2 g/d). Assuming a 10% dropout rate with a type I error rate of 0.05, we plan to enroll 120 participants (40 in each group) in the study.
All results were analyzed based on the intention-to-treat (ITT) analysis. Normally distributed data are expressed as mean ± standard deviation (SD), while non-normally distributed data are expressed as the median of the interquartile interval (IQR). The groups were compared using an independent sample T-test (for a continuous variable with a normal distribution), Wilcoxon rank-sum test (for a continuous variable with non-normal distribution), or chi-square test (for a nominal variable). The missing value is filled up by the last-observation-carried-forward method. For the initial analysis, we will not adjust for confounders or stratification, and for the secondary analysis, we will adjust for confounders for subgroup analyses, such as baseline proteinuria (3g/day), renal function (eGFR 45m1/min per 1.73m2), blood pressure level (systolic blood pressure 140mmHg), MEST-C score, and the new international risk-prediction score. SAS 9.4 (SAS Institute Inc) will be used as statistical analysis tool. A 2-side P ༜ 0.05 was considered statistically significant.