Home blood pressure-lowering effect of a non-steroidal mineralocorticoid receptor blocker, esaxerenone, versus trichlormethiazide for uncontrolled hypertension: the EXCITE-HT randomized controlled study.

The EXCITE-HT study aimed to evaluate the efficacy and safety of esaxerenone versus thiazide diuretics (trichlormethiazide) as second-line treatment for Japanese patients with uncontrolled essential hypertension. This was a 12-week, multicenter, randomized, open-label, parallel-group study. The non-inferiority of esaxerenone to trichlormethiazide was confirmed if the upper limit of the two-sided 95% confidence interval (CI) for the difference in systolic blood pressure (SBP)/diastolic blood pressure (DBP) change between groups was below 3.9/2.1 mmHg. A total of 295 and 290 patients were included in the esaxerenone and trichlormethiazide groups, respectively. The non-inferiority of esaxerenone to trichlormethiazide was demonstrated: least squares mean change differences in morning home SBP/DBP at end of treatment (EOT) were -2.2 (95% CI, -3.6, -0.8) mmHg for SBP/-0.6 (-1.4, 0.2) mmHg for DBP. Morning home, bedtime home, and office BP significantly decreased (all p < 0.001) from baseline to EOT in both groups. The urinary albumin-to-creatinine ratio and N-terminal pro-brain natriuretic peptide level decreased from baseline to Week 12 in both groups, with no notable intergroup difference. Serum potassium elevations occurred more frequently with esaxerenone, while serum potassium reductions occurred more with trichlormethiazide. Uric acid elevations were observed in both groups, but more frequently with trichlormethiazide than esaxerenone. No cases of gout occurred in this study. Reductions in estimated glomerular filtration rate were similarly observed in both groups. EXCITE-HT is the first randomized controlled study to demonstrate evidence that esaxerenone is non-inferior to trichlormethiazide as second-line treatment for Japanese patients with uncontrolled essential hypertension, with no new safety concerns. The EXCITE-HT study demonstrated the non-inferiority of esaxerenone to trichlormethiazide in its morning home blood pressure lowering effect and safety profile in Japanese patients with uncontrolled essential hypertension who were previously treated with an angiotensin II receptor blocker or calcium channel blocker.

Angiotensin-Converting Enzyme Inhibitors or Angiotensin-Receptor Blockers for Advanced Chronic Kidney Disease : A Systematic Review and Retrospective Individual Participant-Level Meta-analysis of Clinical Trials.

BACKGROUND: In patients with advanced chronic kidney disease (CKD), the effects of initiating treatment with an angiotensin-converting enzyme inhibitor (ACEi) or angiotensin-receptor blocker (ARB) on the risk for kidney failure with replacement therapy (KFRT) and death remain unclear. PURPOSE: To examine the association of ACEi or ARB treatment initiation, relative to a non-ACEi or ARB comparator, with rates of KFRT and death. DATA SOURCES: Ovid Medline and the Chronic Kidney Disease Epidemiology Collaboration Clinical Trials Consortium from 1946 through 31 December 2023. STUDY SELECTION: Completed randomized controlled trials testing either an ACEi or an ARB versus a comparator (placebo or antihypertensive drugs other than ACEi or ARB) that included patients with a baseline estimated glomerular filtration rate (eGFR) below 30 mL/min/1.73 m2. DATA EXTRACTION: The primary outcome was KFRT, and the secondary outcome was death before KFRT. Analyses were done using Cox proportional hazards models according to the intention-to-treat principle. Prespecified subgroup analyses were done according to baseline age (<65 vs. ≥65 years), eGFR (<20 vs. ≥20 mL/min/1.73 m2), albuminuria (urine albumin-creatinine ratio <300 vs. ≥300 mg/g), and history of diabetes. DATA SYNTHESIS: A total of 1739 participants from 18 trials were included, with a mean age of 54.9 years and mean eGFR of 22.2 mL/min/1.73 m2, of whom 624 (35.9%) developed KFRT and 133 (7.6%) died during a median follow-up of 34 months (IQR, 19 to 40 months). Overall, ACEi or ARB treatment initiation led to lower risk for KFRT (adjusted hazard ratio, 0.66 [95% CI, 0.55 to 0.79]) but not death (hazard ratio, 0.86 [CI, 0.58 to 1.28]). There was no statistically significant interaction between ACEi or ARB treatment and age, eGFR, albuminuria, or diabetes (P for interaction > 0.05 for all). LIMITATION: Individual participant-level data for hyperkalemia or acute kidney injury were not available. CONCLUSION: Initiation of ACEi or ARB therapy protects against KFRT, but not death, in people with advanced CKD. PRIMARY FUNDING SOURCE: National Institutes of Health. (PROSPERO: CRD42022307589).

A meta-analysis of randomized controlled clinical trials for implications of acute treatment effects on glomerular filtration rate for long-term kidney protection.

Pharmacologic interventions to slow chronic kidney disease progression, such as ACE-inhibitors, angiotensin receptor blockers, or sodium glucose co-transporter 2 inhibitors, often produce acute treatment effects on glomerular filtration rate (GFR) that differ from their long-term chronic treatment effects. Observational studies assessing the implications of acute effects cannot distinguish acute effects from GFR changes unrelated to the treatment. Here, we performed meta-regression analysis of multiple trials to isolate acute effects to determine their long-term implications. In 64 randomized controlled trials (RCTs), enrolling 154,045 participants, we estimated acute effects as the mean between-group difference in GFR slope from baseline to three months, effects on chronic GFR slope (starting at three months after randomization), and effects on three composite kidney endpoints defined by kidney failure (GFR 15 ml/min/1.73m2 or less, chronic dialysis, or kidney transplantation) or sustained GFR declines of 30%, 40% or 57% decline, respectively. We used Bayesian meta-regression to relate acute effects with treatment effects on chronic slope and the composite kidney endpoints. Overall, acute effects were not associated with treatment effects on chronic slope. Acute effects were associated with the treatment effects on composite kidney outcomes such that larger negative acute effects were associated with lesser beneficial effects on the composite kidney endpoints. Associations were stronger when the kidney composite endpoints were defined by smaller thresholds of GFR decline (30% or 40%). Results were similar in a subgroup of interventions with supposedly hemodynamic effects that acutely reduce GFR. For studies with GFR 60 mL/min/1.73m2 or under, negative acute effects were associated with larger beneficial effects on chronic GFR slope. Thus, our data from a large and diverse set of RCTs suggests that acute effects of interventions may influence the treatment effect on clinical kidney outcomes.

The comparison of four hypoxia-inducible factor prolyl hydroxylase inhibitors on drug potency and cost for treatment in patients with renal anemia.

BACKGROUND: Five hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) have been approved for marketing in Japan. However, marked differences exist in terms of drug potency, dose requirement, and pharmacokinetics. METHODS: The primary evaluation in this study was the changes in hemoglobin levels, dose escalation, drug potency, and cost among HIF-PHIs, 3 months after the initiation of treatment. RESULTS: All patients treated with HIF-PHI between August 2020 and December 2023 were enrolled in this study. In total, 124 patients were administered daprodustat (N = 37), enarodustat (N = 44), molidustat (N = 13), or vadadustat (N = 30). The mean hemoglobin levels of daprodustat, enarodustat, molidustat, and vadadustat at 3 months were 11.7 g/dL, 11.8 g/dL, 12.2 g/dL, and 11.3 g/dL, respectively. At 3 months, the mean doses of daprodustat, enarodustat, molidustat, and vadadustat increased by 110%, 177%, 125%, and 152%, respectively, from the initial dose. The HIF-PHI potency indices (HPI) of daprodustat, enarodustat, molidustat, and vadadustat at 3 months were 0.168, 0.307, 0.184, and 0.254, respectively. At 3 months, the mean daily costs of daprodustat, enarodustat, molidustat, and vadadustat were JPY 345, JPY 434, JPY 206, and JPY 565, respectively. CONCLUSION: The difference in dose escalation for anemia treatment among HIF-PHIs is due to differences in drug potency, where the HPI significantly differs among HIF-PHIs. The disparity between the HPI and the cost of the initial dose accounts for the variance in the daily costs of renal anemia treatment among HIF-PHIs.

The Comparison between Vadadustat and Daprodustat Regarding Dose, Cost, and Safety of Treatment for Renal Anemia in Non-dialysis Patients with Chronic Kidney Diseases.

Objective We retrospectively compared the dose, cost, and safety of vadadustat and daprodustat for the treatment of renal anemia in patients with chronic kidney diseases who were not undergoing dialysis. Methods The primary outcome of this study was the change in dose and cost from the initiation of vadadustat and daprodustat treatment. The secondary outcome was the drug safety. Patients We treated 30 patients each with the hypoxia-inducible factor prolyl-hydroxylase inhibitors (HIF-PHIs) daprodustat and vadadustat. The hemoglobin (Hb) concentration was targeted at 11-13 g/dL, and transferrin saturation was maintained at ≥20%, as per the 2018 Japanese guidelines for the diagnosis and treatment of chronic kidney disease. Results Hb levels increased from 10.7 to 11.5 g/dL after the first month of daprodustat administration, whereas those for vadadustat patients remained relatively stable, going from 10.7 to 10.6 g/dL. After six months, the Hb level reached 12.1 g/dL and 11.3 g/dL for daprodustat and vadadustat, respectively. The dosage of vadadustat was significantly increased by 46% and 70% after 3 and 12 months, respectively, compared with the initial doses, whereas that of daprodustat did not change substantially. The average cost of vadadustat also increased in the first 3 months and remained over 500 yen/day after 3 months, while that of daprodustat showed little change from the initial cost of 360 yen/day. Conclusion These results suggest that heterogeneity exists in the drug potency and dosage required for treatment between daprodustat and vadadustat. Serious adverse events (death, cardiovascular disease, end stage renal disease (ESRD), and malignancy) occurred in more than 20% of participants with both HIF-PHIs. Further studies are required to confirm the safety of HIF-PHIs.

Higher hemoglobin levels using darbepoetin alfa and kidney outcomes in advanced chronic kidney disease without diabetes: a prespecified secondary analysis of the PREDICT trial.

BACKGROUND: In the primary analysis of the PREDICT trial, a higher hemoglobin target (11-13 g/dl) with darbepoetin alfa did not improve renal outcomes compared with a lower hemoglobin target (9-11 g/dl) in advanced chronic kidney disease (CKD) without diabetes. Prespecified secondary analyses were performed to further study the effects of targeting higher hemoglobin levels on renal outcomes. METHODS: Patients with an estimated glomerular filtration rate (eGFR) 8-20 ml/min/1.73 m2 without diabetes were randomly assigned 1:1 to the high- and low-hemoglobin groups. The differences between the groups were evaluated for the following endpoints and cohort sets: eGFR and proteinuria slopes, assessed using a mixed-effects model in the full analysis set and the per-protocol set that excluded patients with off-target hemoglobin levels; the primary endpoint of composite renal outcome, evaluated in the per-protocol set using the Cox model. RESULTS: In the full analysis set (high hemoglobin, n = 239; low hemoglobin, n = 240), eGFR and proteinuria slopes were not significantly different between the groups. In the per-protocol set (high hemoglobin, n = 136; low hemoglobin, n = 171), the high-hemoglobin group was associated with reduced composite renal outcome (adjusted hazard ratio: 0.64; 95% confidence interval: 0.43-0.96) and an improved eGFR slope (coefficient: + 1.00 ml/min/1.73 m2/year; 95% confidence interval: 0.38-1.63), while the proteinuria slope did not differ between the groups. CONCLUSIONS: In the per-protocol set, the high-hemoglobin group demonstrated better kidney outcomes than the low-hemoglobin group, suggesting a potential benefit of maintaining higher hemoglobin levels in patients with advanced CKD without diabetes. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov (identifier: NCT01581073).

A meta-analysis of GFR slope as a surrogate endpoint for kidney failure.

Glomerular filtration rate (GFR) decline is causally associated with kidney failure and is a candidate surrogate endpoint for clinical trials of chronic kidney disease (CKD) progression. Analyses across a diverse spectrum of interventions and populations is required for acceptance of GFR decline as an endpoint. In an analysis of individual participant data, for each of 66 studies (total of 186,312 participants), we estimated treatment effects on the total GFR slope, computed from baseline to 3 years, and chronic slope, starting at 3 months after randomization, and on the clinical endpoint (doubling of serum creatinine, GFR < 15 ml min-1 per 1.73 m2 or kidney failure with replacement therapy). We used a Bayesian mixed-effects meta-regression model to relate treatment effects on GFR slope with those on the clinical endpoint across all studies and by disease groups (diabetes, glomerular diseases, CKD or cardiovascular diseases). Treatment effects on the clinical endpoint were strongly associated with treatment effects on total slope (median coefficient of determination (R2) = 0.97 (95% Bayesian credible interval (BCI) 0.82-1.00)) and moderately associated with those on chronic slope (R2 = 0.55 (95% BCI 0.25-0.77)). There was no evidence of heterogeneity across disease. Our results support the use of total slope as a primary endpoint for clinical trials of CKD progression.

Change in Albuminuria and GFR Slope as Joint Surrogate End Points for Kidney Failure: Implications for Phase 2 Clinical Trials in CKD.

SIGNIFICANCE STATEMENT: Changes in albuminuria and GFR slope are individually used as surrogate end points in clinical trials of CKD progression, and studies have demonstrated that each is associated with treatment effects on clinical end points. In this study, the authors sought to develop a conceptual framework that combines both surrogate end points to better predict treatment effects on clinical end points in Phase 2 trials. The results demonstrate that information from the combined treatment effects on albuminuria and GFR slope improves the prediction of treatment effects on the clinical end point for Phase 2 trials with sample sizes between 100 and 200 patients and duration of follow-up ranging from 1 to 2 years. These findings may help inform design of clinical trials for interventions aimed at slowing CKD progression. BACKGROUND: Changes in log urinary albumin-to-creatinine ratio (UACR) and GFR slope are individually used as surrogate end points in clinical trials of CKD progression. Whether combining these surrogate end points might strengthen inferences about clinical benefit is unknown. METHODS: Using Bayesian meta-regressions across 41 randomized trials of CKD progression, we characterized the combined relationship between the treatment effects on the clinical end point (sustained doubling of serum creatinine, GFR <15 ml/min per 1.73 m 2 , or kidney failure) and treatment effects on UACR change and chronic GFR slope after 3 months. We applied the results to the design of Phase 2 trials on the basis of UACR change and chronic GFR slope in combination. RESULTS: Treatment effects on the clinical end point were strongly associated with the combination of treatment effects on UACR change and chronic slope. The posterior median meta-regression coefficients for treatment effects were -0.41 (95% Bayesian Credible Interval, -0.64 to -0.17) per 1 ml/min per 1.73 m 2 per year for the treatment effect on GFR slope and -0.06 (95% Bayesian Credible Interval, -0.90 to 0.77) for the treatment effect on UACR change. The predicted probability of clinical benefit when considering both surrogates was determined primarily by estimated treatment effects on UACR when sample size was small (approximately 60 patients per treatment arm) and follow-up brief (approximately 1 year), with the importance of GFR slope increasing for larger sample sizes and longer follow-up. CONCLUSIONS: In Phase 2 trials of CKD with sample sizes of 100-200 patients per arm and follow-up between 1 and 2 years, combining information from treatment effects on UACR change and GFR slope improved the prediction of treatment effects on clinical end points.

Evaluation of Variation in the Performance of GFR Slope as a Surrogate End Point for Kidney Failure in Clinical Trials that Differ by Severity of CKD.

BACKGROUND: The GFR slope has been evaluated as a surrogate end point for kidney failure in meta-analyses on a broad collection of randomized controlled trials (RCTs) in CKD. These analyses evaluate how accurately a treatment effect on GFR slope predicts a treatment effect on kidney failure. We sought to determine whether severity of CKD in the patient population modifies the performance of GFR slope. METHODS: We performed Bayesian meta-regression analyses on 66 CKD RCTs to evaluate associations between effects on GFR slope (the chronic slope and the total slope over 3 years, expressed as mean differences in ml/min per 1.73 m2/yr) and those of the clinical end point (doubling of serum creatinine, GFR <15 ml/min per 1.73 m2, or kidney failure, expressed as a log-hazard ratio), where models allow interaction with variables defining disease severity. We evaluated three measures (baseline GFR in 10 ml/min per 1.73 m2, baseline urine albumin-to-creatinine ratio [UACR] per doubling in mg/g, and CKD progression rate defined as the control arm chronic slope, in ml/min per 1.73 m2/yr) and defined strong evidence for modification when 95% posterior credible intervals for interaction terms excluded zero. RESULTS: There was no evidence for modification by disease severity when evaluating 3-year total slope (95% credible intervals for the interaction slope: baseline GFR [-0.05 to 0.03]; baseline UACR [-0.02 to 0.04]; CKD progression rate [-0.07 to 0.02]). There was strong evidence for modification in evaluations of chronic slope (95% credible intervals: baseline GFR [0.02 to 0.11]; baseline UACR [-0.11 to -0.02]; CKD progression rate [0.01 to 0.15]). CONCLUSIONS: These analyses indicate consistency of the performance of total slope over 3 years, which provides further evidence for its validity as a surrogate end point in RCTs representing varied CKD populations.

Hyporesponsiveness to erythropoiesis-stimulating agent in non-dialysis-dependent CKD patients: The BRIGHTEN study.

Among non-dialysis-dependent chronic kidney disease (ND-CKD) patients, a low hematopoietic response to erythropoiesis-stimulating agents (ESAs) is a predictor for poor renal and cardiovascular outcome. To assess the method for evaluating hyporesponsiveness to ESA in patients with ND-CKD, a multicenter, prospective, observational study of 1,980 adult patients with ND-CKD with renal anemia was conducted. Darbepoetin alfa (DA) and iron supplement administrations were provided according to the recommendation of the attached document and the guidelines of JSDT (Japanese Society of Dialysis and Transplantation). The primary outcomes were progression of renal dysfunction and major adverse cardiovascular events. ESA responsiveness was assessed using pre-defined candidate formulae. During the mean follow-up period of 96 weeks, renal and cardiovascular disease (CVD) events occurred in 683 (39.6%) and 174 (10.1%) of 1,724 patients, respectively. Among pre-set candidate formulae, the one expressed by dividing the dose of DA by Hb level at the 12-week DA treatment was statistically significant in predicting renal (hazard ratio [HR], 1.449; 95% confidence interval [CI], 1.231-1.705; P<0.0001) and CVD events (HR, 1.719; 95% CI, 1.239-2.386; P = 0.0010). The optimum cut-off values for both events were close to 5.2. In conclusion, hyporesponsiveness to ESA in ND-CKD cases, which is associated with a risk for renal and CVD events, may be evaluated practicably as the dose of DA divided by the Hb level at the 12-week DA treatment, and the cut-off value of this index is 5.2. A search for the causes of poor response and measures for them should be recommended in such patients. Trial registration: ClinicalTrials. gov Identifier: NCT02136563; UMIN Clinical Trial Registry Identifier: UMIN000013464.

Deep learning analysis of clinical course of primary nephrotic syndrome: Japan Nephrotic Syndrome Cohort Study (JNSCS).

BACKGROUND: Prognosis of nephrotic syndrome has been evaluated based on pathological diagnosis, whereas its clinical course is monitored using objective items and the treatment strategy is largely the same. We examined whether the entire natural history of nephrotic syndrome could be evaluated using objective common clinical items. METHODS: Machine learning clustering was performed on 205 cases from the Japan Nephrotic Syndrome Cohort Study, whose clinical parameters, serum creatinine, serum albumin, dipstick hematuria, and proteinuria were traceable after kidney biopsy at 5 measured points up to 2 years. The clinical patterns of time-series data were learned using long short-term memory (LSTM)-encoder-decoder architecture, an unsupervised machine learning classifier. Clinical clusters were defined as Gaussian mixture distributions in a two-dimensional scatter plot based on the highest log-likelihood. RESULTS: Time-series data of nephrotic syndrome were classified into four clusters. Patients in the fourth cluster showed the increase in serum creatinine in the later part of the follow-up period. Patients in both the third and fourth clusters were initially high in both hematuria and proteinuria, whereas a lack of decline in the urinary protein level preceded the worsening of kidney function in fourth cluster. The original diseases of fourth cluster included all the disease studied in this cohort. CONCLUSIONS: Four kinds of clinical courses were identified in nephrotic syndrome. This classified clinical course may help objectively grasp the actual condition or treatment resistance of individual patients with nephrotic syndrome.

Effect of Pemafibrate on Serum Creatinine in Patients with Chronic Kidney Disease.

Introduction: Fibrates are recommended not to be used for the treatment of hypertriglyceridemia in patients with chronic kidney disease (CKD) based on clinical practice guidelines. The major reason for the negative suggestion is the elevation of serum creatinine and rhabdomyolysis by fibrates. This may cause clinical inertia for the treatment of hypertriglyceridemia using fibrate in patients with CKD, who are associated with an increasing risk of cardiovascular disease. Methods: We retrospectively studied the change of serum creatinine via the treatment of pemafibrate. Results: A total of 39 patients with CKD were treated with 0.2 mg of pemafibrate. Serum triglyceride was decreased in 23 fibrate-naïve patients from 380 [308, 455] mg/dL to 180 [152, 215] mg/dL via treatment with pemafibrate (p = 0.00003). Serum creatinine and eGFR were not changed from 1.22 ± 0.29 mg/dL to 1.21 ± 0.28 mg/dL (p = 0.70) and from 45.7 ± 10.9 mL/min/1.73 m2 to 46.2 ± 12.0 mL/min/1.73 m2 (p = 0.67) via treatment with pemafibrate, respectively. In 16 patients, with a change of treatment from fenofibrate or bezafibrate to pemafibrate, serum creatinine was significantly decreased from 1.32 ± 0.36 mg/dL to 1.17 ± 0.24 mg/dL (p = 0.003). eGFR was significantly increased from 45.2 ± 9.9 mL/min/1.73 m2 to 50.1 ± 8.6 mL/min/1.73 m2 (p = 0.001). Conclusions: These results suggest that treatment with pemafibrate does not affect the serum creatinine level and is suitable for use in patients with CKD for the treatment of hypertriglyceridemia.

Predictors of early remission of proteinuria in adult patients with minimal change disease: a retrospective cohort study.

Previous studies reported conflicting results regarding an association between serum albumin concentration and the cumulative incidence of remission of proteinuria in adult patients with minimal change disease (MCD). The present study aimed to clarify the clinical impact of serum albumin concentration and the cumulative incidence of remission and relapse of proteinuria in 108 adult patients with MCD at 40 hospitals in Japan, who were enrolled in a 5-year prospective cohort study of primary nephrotic syndrome, the Japan Nephrotic Syndrome Cohort Study (JNSCS). The association between serum albumin concentration before initiation of immunosuppressive treatment (IST) and the cumulative incidence of remission and relapse were assessed using multivariable-adjusted Cox proportional hazards models. Remission defined as urinary protein < 0.3 g/day (or g/gCr) was observed in 104 (96.3%) patients. Of 97 patients with remission within 6 month of IST, 42 (43.3%) developed relapse defined as ≥ 1.0 g/day (or g/gCr) or dipstick urinary protein of ≥ 2+. Serum albumin concentration was significantly associated with remission (multivariable-adjusted hazard ratio [95% confidence interval] per 1.0 g/dL, 0.57 [0.37, 0.87]), along with eGFR (per 30 mL/min/1.73 m2: 1.43 [1.08, 1.90]), whereas they were not associated with relapse. A multivariable-adjusted model showed that patients with high eGFR level (≥ 60 mL/min/1.73 m2) and low albumin concentration (≤ 1.5 g/dL) achieved significantly early remission, whereas those with low eGFR (< 60 mL/min/1.73 m2) and high albumin concentration (> 1.5 g/dL) showed significantly slow remission. In conclusion, lower serum albumin concentration and higher eGFR were associated with earlier remission in MCD, but not with relapse.

Time to remission of proteinuria and incidence of relapse in patients with steroid-sensitive minimal change disease and focal segmental glomerulosclerosis: the Japan Nephrotic Syndrome Cohort Study.

BACKGROUND: Minimal change disease (MCD) is characterized by a nephrotic syndrome usually steroid-sensitive and a high incidence of relapse of proteinuria. Previous cohort studies have reported conflicting results regarding the association between the time to remission and incidence of relapse. METHODS: This multicenter prospective cohort study included 102 adult patients with steroid-sensitive MCD or focal segmental glomerulosclerosis from a 5-year cohort study of primary nephrotic syndrome, the Japan Nephrotic Syndrome Cohort Study, who achieved remission of proteinuria within 2 months of immunosuppressive therapy (IST). The association between the time to remission of proteinuria after immunosuppressive therapy and incidence of relapse was assessed using Cox proportional hazards models adjusted for clinically relevant factors. RESULTS: Remission was observed at 3-7, 8-14, 15-21, 22-28, and 30-56 days after initiation of immunosuppressive therapy in 17 (16.7%), 37 (36.3%), 21 (20.6%), 13 (12.7%), and 14 (13.7%) patients, respectively. During a median observation period of 2.3 years after the end of the 2nd month after initiation of immunosuppressive therapy, 46 (45.1%) patients relapsed. The time to remission was associated with the incidence of relapse in an inverse U-shaped pattern (multivariable-adjusted hazard ratios [95% confidence intervals] of the time to remission of 3-7, 8-14, 15-21, 22-28, 30-56 days: 1.00 [reference], 1.76 [0.56, 5.51], 6.06 [1.85, 19.80], 5.46 [1.44, 20.64], and 2.19 [0.52, 9.30], respectively). CONCLUSION: The time to remission was identified as a significant predictor of relapse in steroid-sensitive patients.

A Comparative Study of Serum Phosphate and Related Parameters in Chronic Kidney Disease between the USA and Japan.

INTRODUCTION: Recent studies have suggested a higher incidence of cardiovascular disease (CVD) among patients with chronic kidney disease (CKD) in the USA than in Japan. Hyperphosphatemia, a possible risk for CVD, may explain this difference; however, international differences in phosphate parameters in CKD have not been well elaborated. METHODS: By using the baseline data from the USA and the Japanese nation-wide, multicenter, CKD cohort studies; the Chronic Renal Insufficiency Cohort Study (CRIC, N = 3,870) and the Chronic Kidney Disease-Japan Cohort Study (CKD-JAC, N = 2,632), we harmonized the measures and compared clinical parameters regarding phosphate metabolism or serum phosphate, fibroblast growth factor-23 (FGF23), and parathyroid hormone (PTH), in the cross-sectional model. RESULTS: Multivariable linear regression analyses revealed that serum phosphate levels were significantly higher in CRIC across all levels of estimated glomerular filtration rate (eGFR) with the greatest difference being observed at lower levels of eGFR. Serum FGF23 and 25-hydroxy vitamin D (25OHD) levels were higher in CRIC, while PTH levels were higher in CKD-JAC at all levels of eGFR. Adjustments for demographics, 25OHD, medications, dietary intake or urinary excretion of phosphate, PTH, and FGF23 did not eliminate the difference in serum phosphate levels between the cohorts (0.43, 0.46, 0.54, 0.64, and 0.78 mg/dL higher in CRIC within eGFR strata of >50, 41-50, 31-40, 21-30, and ≤20 mL/min/1.73 m2, respectively). These findings were consistent when only Asian CRIC participants (N = 105) were included in the analysis. CONCLUSION: Serum phosphate levels in CRIC were significantly higher than those of CKD-JAC across all stages of CKD, which may shed light on the international variations in phosphate parameters and thus in cardiovascular risk among CKD patients. The key mechanisms for the substantial differences in phosphate parameters need to be elucidated.

Acute Treatment Effects on GFR in Randomized Clinical Trials of Kidney Disease Progression.

BACKGROUND: Acute changes in GFR can occur after initiation of interventions targeting progression of CKD. These acute changes complicate the interpretation of long-term treatment effects. METHODS: To assess the magnitude and consistency of acute effects in randomized clinical trials and explore factors that might affect them, we performed a meta-analysis of 53 randomized clinical trials for CKD progression, enrolling 56,413 participants with at least one estimated GFR measurement by 6 months after randomization. We defined acute treatment effects as the mean difference in GFR slope from baseline to 3 months between randomized groups. We performed univariable and multivariable metaregression to assess the effect of intervention type, disease state, baseline GFR, and albuminuria on the magnitude of acute effects. RESULTS: The mean acute effect across all studies was -0.21 ml/min per 1.73 m2 (95% confidence interval, -0.63 to 0.22) over 3 months, with substantial heterogeneity across interventions (95% coverage interval across studies, -2.50 to +2.08 ml/min per 1.73 m2). We observed negative average acute effects in renin angiotensin system blockade, BP lowering, and sodium-glucose cotransporter 2 inhibitor trials, and positive acute effects in trials of immunosuppressive agents. Larger negative acute effects were observed in trials with a higher mean baseline GFR. CONCLUSION: The magnitude and consistency of acute GFR effects vary across different interventions, and are larger at higher baseline GFR. Understanding the nature and magnitude of acute effects can help inform the optimal design of randomized clinical trials evaluating disease progression in CKD.

Initial responsiveness to darbepoetin alfa and its contributing factors in non-dialysis chronic kidney disease patients in Japan.

BACKGROUND: Hyporesponsiveness to erythropoiesis-stimulating agents (ESAs) is associated with cardiovascular events and poor renal outcome in patients with chronic kidney disease (CKD). This study aimed to investigate the initial responsiveness to darbepoetin alfa (DA) and its contributing factors using the data from the BRIGHTEN. METHODS: Of 1980 patients enrolled at 168 facilities, 1695 were included in this analysis [285 patients were excluded mainly due to lack of hemoglobin (Hb) values]. The initial ESA response index (iEResI) was defined as a ratio of Hb changes over 12 weeks after DA administration per weight-adjusted total DA dose and contributing factors to iEResI were analyzed. RESULTS: The mean age was 70 ± 12 years (male 58.8%; diabetic nephropathy 27.6%). The median creatinine and mean Hb levels at DA initiation were 2.62 mg/dL and 9.8 g/dL, respectively. The most frequent number of DA administration during 12 weeks was 3 times (41.1%), followed by 4 (15.6%) times with a wide distribution of the total DA dose (15-900 µg). Remarkably, 225 patients (13.3%) did not respond to DA. Multivariate analysis showed that male gender, hypoglycemic agent use, iron supplementation, high eGFR, low Hb, low CRP, low NT-proBNP, and low urinary protein-creatinine ratio were independently associated with better initial response to DA (P = < 0.0001, 0.0108, < 0.0001, 0.0476, < 0.0001, 0.0004, 0.0435, and 0.0009, respectively). CONCLUSIONS: Non-responder to DA accounted for 13.3% of patients with non-dialysis CKD. Iron supplementation, low CRP, low NT-proBNP, and less proteinuria were predictive and modifiable factors associated with better initial response to DA.

Better remission rates in elderly Japanese patients with primary membranous nephropathy in nationwide real-world practice: The Japan Nephrotic Syndrome Cohort Study (JNSCS).

BACKGROUND: The aim of the present study was to clarify the prevalence of immunosuppressive drug use and outcomes in elderly and non-elderly patients with primary membranous nephropathy (MN) in nationwide real-world practice in Japan. PATIENTS AND METHODS: Between 2009 and 2010, 374 patients with primary nephrotic syndrome were enrolled in the cohort study (The Japan Nephrotic Syndrome Cohort Study, JNSCS), including 126 adult patients with MN. Their clinical characteristics were compared with those of nephrotic patients with primary MN registered in a large nationwide registry (The Japan Renal Biopsy Registry, J-RBR). Outcomes and predictors in the elderly (≥ 65 years) and non-elderly groups were identified. RESULTS: Similar clinical characteristics were observed in JNSCS patients and J-RBR patients (n = 1808). At the early stage of 1 month, 84.1% of patients were treated with immunosuppressive therapies. No significant differences were observed in therapies between age groups. However, elderly patients achieved complete remission (CR) more frequently than non-elderly patients, particularly those treated with therapies that included corticosteroids. No significant differences were noted in serum creatinine (sCr) elevations at 50 or 100%, end-stage kidney disease, or all-cause mortality between age groups. Corticosteroids were identified as an independent predictor of CR (HR 2.749, 95%CI 1.593-4.745, p = 0.000) in the multivariate Cox's model. sCr levels, hemoglobin levels, immunosuppressants, clinical remission, and relapse after CR were independent predictors of sCr × 1.5 or × 2.0. CONCLUSION: Early immunosuppressive therapy including corticosteroids for primary MN showed better remission rates in elderly patients in a nationwide cohort study.