Ethnic differences in 25-hydroxyvitamin D levels and response to treatment in CKD

Pharmacokinetics, Pharmacodynamics, and Safety Evaluation of the Novel HIF-PH Inhibitor Enarodustat: An Open-Label Phase I Study in Healthy Chinese Participants

BACKGROUND AND OBJECTIVES

Enarodustat is a hypoxia-inducible factor-prolyl hydroxylase inhibitor. We evaluated the pharmacokinetics, pharmacodynamics, and safety profile of domestic enarodustat (SAL-0951) and analyzed the influence of ethnic factors.

METHODS

In this phase I study, healthy Chinese participants received single and multiple oral doses (1, 5, and 15 mg) of SAL-0951 while in a fasted state. We monitored the pharmacokinetics, pharmacodynamics, and safety characteristics and analyzed the impact of ethnicity on pharmacokinetic characteristics.

RESULTS

In total, 33 healthy Chinese participants were enrolled; the mean age was 31.2 ± a standard deviation of 5.5 years. After single doses of 1, 5, and 15 mg were administered under fasted conditions, SAL-0951 was rapidly absorbed. Mean maximum plasma concentration and area under the plasma concentration-time curve from time 0 to the last quantifiable concentration increased dose proportionately from 0.14 to 2.54 μg/mL and from 0.63 to 9.50 h × μg/mL, respectively. The elimination half-life was 6.13, 6.32, and 6.74 h, respectively, in these three groups, and the mean value of apparent clearance ranged from 1.64 to 1.89 L/h. SAL-0951 was excreted mostly as the parent compound. It reached a stable concentration after 5 days of multiple-dose administration. We observed no drug accumulation or time-dependent pharmacokinetic characteristics and no significant difference in pharmacokinetic characteristics between Chinese and Japanese participants.

CONCLUSION

SAL-0951 was safe and well tolerated in healthy Chinese participants and had a linear pharmacokinetic profile. We found no ethnic differences in the pharmacokinetic characteristics of the drug between Chinese and Japanese populations.

CLINICAL TRIAL REGISTRATION

Registered at Chinadrugtrials.org.cn, registration number CTR2020245.

Vitamin D status of children with moderate to severe chronic Kidney Disease at a Tertiary Pediatric Center in Cape Town

The prevalence of suboptimal Vitamin D levels is higher in patients with chronic kidney disease (CKD) than in the general population. Recent findings suggest that progression of CKD is linked to a suboptimal Vitamin D level. A high percentage of CKD patients have severe Vitamin D deficiency. These patients also have a low level of 25-hydroxy-vitamin D [25(OH)D] and consequently, a reduced ability to form active 1,25-dihydroxyvitamin D. Various factors underlie the low level of 25(OH)D, including a sedentary lifestyle, decreased intake of Vitamin D due to CKD-related dietary restrictions, and decreased synthesis of Vitamin D in skin due to uremia. All these factors may be particularly influential in patients with progressively worsening CKD, including those receiving chronic dialysis. The objective of our study is to determine the prevalence of Vitamin D deficiency in children with CKD stages three to five and those receiving chronic dialysis, to ascertain whether there is a relationship between Vitamin D deficiency and the stage of CKD, and to identify any clinical correlates associated with the Vitamin D status. A single-center, retrospective review was conducted of 46 children (younger than 18 years) with CKD stages 3-5D who attended the renal clinic of the Red Cross Children's Hospital between October 2013 and November 2014. In total, 73.9% of the study population had suboptimal Vitamin D levels (43.5% and 30.4% had Vitamin D deficiency and insufficiency, respectively). The prevalence of Vitamin D deficiency was significantly higher in older children (≥10 years of age) than in younger children (P = 0.000) but did not significantly differ between males and females (P = 0.693). In total, 12 of 15 black children (80%), 19 of 26 colored children (73.1%), two of four white children (50%), and one Asian child (100%) had suboptimal Vitamin D levels. Neither white nor Asian child had Vitamin D deficiency. In addition, 90% of patients undergoing chronic dialysis, 80% of whom were receiving peritoneal dialysis, had suboptimal Vitamin D levels. Age, weight, height, and the albumin concentration were significantly associated with the Vitamin D level. There was a positive linear relationship between the Vitamin D level and the serum albumin concentration (Spearman's rho correlation coefficient = 0.397, P = 0.007). In total, 87.5% of patients with nephrotic-range proteinuria had suboptimal Vitamin D levels, and 80% were Vitamin D deficient (P = 0.004). A higher percentage of Vitamin D deficiency/insufficiency cases was documented during the winter (24/34, 70.6%) than during the summer (10/34, 29.4%); however, this difference was not statistically significant (P = 0.685). Sub-optimal Vitamin D is high among children with moderate to severe CKD and significantly higher in those undergoing chronic dialysis. The emerging evidence of the role of Vitamin D in slowing progression of CKD highlights the need for monitoring and correction of Vitamin D levels in predialysis children.

The Effect of Long-Term Cholecalciferol Supplementation on Vascular Calcification in Chronic Kidney Disease Patients With Hypovitaminosis D

OBJECTIVE

The role of vitamin D supplementation on vascular calcification (VC) in patients with chronic kidney disease (CKD) is controversial. The objective of this study was to evaluate the effects of long-term cholecalciferol supplementation on VC in nondialysis patients with CKD stages 3-4 with hypovitaminosis D.

DESIGN AND METHODS

Eighty patients aged 18-85 years with creatinine clearance between 15 and 60 mL/min/1.73 m² and serum 25(OH)D level < 30 ng/mL were enrolled in a 18-month prospective study. Individuals with vitamin D insufficiency (25-hydroxyvitamin D [25(OH)D] level between 16 and 29 ng/mL) were included in a randomized, double-blind, two-arm study to receive cholecalciferol or placebo. Patients with vitamin D deficiency [25(OH)D < 15 ng/mL] were included in an observational study and mandatorily received cholecalciferol. The coronary artery calcium score was obtained by multislice computed tomography at baseline and the 18th month.

RESULTS

During the study, VC did not change in the treated insufficient group (418 [81-611] to 364 [232-817] AU, P = 0.25) but increased in the placebo group (118 [37-421] to 199 [49-490] AU, P = 0.01). The calcium score change was inversely correlated with 25(OH)D change (r = -0.45; P = 0.037) in the treated insufficient group but not in the placebo group. Renal function did not change in the insufficient, treated, and placebo groups. In multivariate analysis, there was no difference in VC progression between the treated and placebo insufficient groups (interaction P = 0.92). In the deficient group, VC progressed (265 [84-733] to 333 [157-745] AU; P = 0.006) and renal function declined (33 [26-43] to 23 [17-49] mL/min/1.73 m²; P = 0.04). The calcium score change was inversely correlated with cholecalciferol cumulative doses (r = -0.41; P = 0.048) and kidney function change (r = -0.43; P = 0.033) but not with 25(OH)D change (r = -0.08; P = 0.69).

CONCLUSION

Vitamin D supplementation did not attenuate VC progression in CKD patients with hypovitaminosis D.

CONCLUSION

Vitamin D supplementation did not attenuate VC progression in CKD patients with hypovitaminosis D.

Association between serum 25-hydroxyvitamin D and glycated hemoglobin levels in type 2 diabetes patients with chronic kidney disease

AIMS/INTRODUCTION

Vitamin D is suggested to influence glucose homeostasis. An inverse relationship between serum 25-hydroxyvitamin D (25[OH]D) and glycemic control in non-chronic kidney disease (CKD) patients with type 2 diabetes was reported. We aimed to examine this association among type 2 diabetes patients with CKD.

MATERIALS AND METHODS

A total of 100 type 2 diabetes participants with stage 3-4 CKD were recruited. Blood for glycated hemoglobin (HbA1c ), serum 25(OH)D, renal and lipid profiles were drawn at enrollment. Correlation and regression analyses were carried out to assess the relationship of serum 25(OH)D, HbA1c and other metabolic traits.

RESULTS

A total of 30, 42, and 28% of participants were in CKD stage 3a, 3b and 4, respectively. The proportions of participants based on ethnicity were 51% Malay, 24% Chinese and 25% Indian. The mean (±SD) age and body mass index were 60.5 ± 9.0 years and 28.3 ± 5.9 kg/m2 , whereas mean HbA1c and serum 25(OH)D were 7.9 ± 1.6% and 37.1 ± 22.2 nmol/L. HbA1c was negatively correlated with serum 25(OH)D (rs = -0.314, P = 0.002), but positively correlated with body mass index (rs = 0.272, P = 0.006) and serum low-density lipoprotein cholesterol (P = 0.006). There was a significant negative correlation between serum 25(OH)D and total daily dose of insulin prescribed (rs = -0.257, P = 0.042). Regression analyses showed that every 10-nmol/L decline in serum 25(OH)D was associated with a 0.2% increase in HbA1c .

CONCLUSIONS

Lower serum 25(OH)D was associated with poorer glycemic control and higher insulin use among multi-ethnic Asians with type 2 diabetes and stage 3-4 CKD.

Cholecalciferol v. ergocalciferol for 25-hydroxyvitamin D (25(OH)D) repletion in chronic kidney disease: a randomised clinical trial

Patients with chronic kidney disease (CKD) demonstrate complex mineral metabolism derangements and a high prevalence of vitamin D deficiency. However, the optimal method of 25-hydroxyvitamin D (25(OH)D) repletion is unknown, and trials analysing the comparative efficacy of cholecalciferol and ergocalciferol in this population are lacking. We conducted a randomised clinical trial of cholecalciferol 1250μg (50 000 IU) weekly v. ergocalciferol 1250μg (50 000 IU) weekly for 12 weeks in forty-four non-dialysis-dependent patients with stage 3-5 CKD. The primary outcome was change in total 25(OH)D from baseline to week 12 (immediately after therapy). Secondary analyses included the change in 1,25-dihydroxyvitamin D (1,25(OH)2D), parathyroid hormone (PTH), D2 and D3 sub-fractions of 25(OH)D and 1,25(OH)2D and total 25(OH)D from baseline to week 18 (6 weeks after therapy). Cholecalciferol therapy yielded a greater change in total 25(OH)D (45·0 (sd 16·5) ng/ml) v. ergocalciferol (30·7 (sd 15·3) ng/ml) from baseline to week 12 (P<0·01); this observation partially resulted from a substantial reduction in the 25(OH)D3 sub-fraction with ergocalciferol. However, following cessation of therapy, no statistical difference was observed for total 25(OH)D change from baseline to week 18 between cholecalciferol and ergocalciferol groups (22·4 (sd 12·7) v. 17·6 (sd 8·9) ng/ml, respectively; P=0·17). We observed no significant difference between these therapies with regard to changes in serum PTH or 1,25(OH)2D. Therapy with cholecalciferol, compared with ergocalciferol, is more effective at raising serum 25(OH)D in non-dialysis-dependent CKD patients while active therapy is ongoing. However, levels of 25(OH)D declined substantially in both arms following cessation of therapy, suggesting the need for maintenance therapy to sustain levels.

Effects of vitamin D supplementation as an adjuvant therapy in coronary artery disease patients

OBJECTIVES

Low vitamin D status has been shown to be associated with coronary artery disease. We planned to research the effects of vitamin D3 supplementation on the severity of coronary artery disease.

DESIGN

We investigated the effect of 0.5 μg vitamin D3 per day in a randomized, placebo-controlled, double-blind study in 90 stable coronary artery disease patients residing in Beijing. Coronary angiography was performed before and after 6 months of treatment that took place between January and June. 25-Hydroxyvitamin D was measured by chemiluminescence assay. Coronary artery disease severity was assessed by using the SYNTAX scores.

RESULTS

In vitamin D supplementation group, there was a significant increase in mean 25-hydroxyvitamin D levels from baseline (19.9 ± 9.8 ng/ml) to 6 months (35.8 ± 12.1 ng/ml; p < 0.001). At 6 months, the primary end point, a difference in the fall of SYNTAX score between the groups was -2.5 (95% CI -5.1 to -0.5; p < 0.001) under intention to treat analysis. Compared with the control group, patients treated with vitamin D3 also had greater decreases in high sensitivity C-reactive protein and renin-angiotensin system activity (p < 0.05).

CONCLUSIONS

Vitamin D supplementation has beneficial effects on coronary artery disease; it can be an adjuvant therapy for patients with coronary artery disease.

Ergocalciferol versus Cholecalciferol for Nutritional Vitamin D Replacement in CKD

BACKGROUND/AIMS

Is cholecalciferol (D3) superior to ergocalciferol (D2) in treating nutritional vitamin D deficiency in chronic kidney disease (CKD)? The answer to this question has not been fully explored.

METHODS

A retrospective analysis of 57 patients with non-dialysis-requiring CKD was conducted to assess the relative effectiveness of D2 versus D3 replacement on circulating 25(OH)D levels. Levels of 25(OH) D were assessed at baseline, after attempted repletion with D2, and then after attempted repletion with D3. The relative paired differences of the drug treatment effects were tested using t-tests. Multiple regression modeling was used to determine the factors significantly associated with differential responsiveness to the drugs.

RESULTS

The mean (SEM) age was 66.4 ± 1.4 and mean eGFR was 40.5 ± 2.2 ml/min/1.73 m(2). The baseline 25(OH)D level was 15.3 ± 0.8 ng/ml. After standardizing to 100,000 units of drug, increases after cholecalciferol (2.7 ± 0.3 ng/ml) were more than twice as great as those from ergocalciferol (1.1 ± 0.3 ng/ml) (p < 0.0001). A sensitivity analysis, which pooled the results of an additional 109 individuals treated with ergocalciferol alone, revealed similar findings (standardized change 2.7 ± 0.3 vs. 1.6 ± 0.3 ng/ml, p = 0.0025). Factors associated with a superior response to cholecalciferol were lower baseline 25(OH) D level at the start of therapy (p = 0.015) and the interaction of sex and age (p = 0.0048), with younger females tending to benefit relatively more from cholecalciferol than older males did.

CONCLUSION

Cholecalciferol may be superior to ergocalciferol in treating nutritional vitamin D deficiency in non-dialysis CKD.

Effects of vitamin D on plasma lipid profiles in statin-treated patients with hypercholesterolemia: A randomized placebo-controlled trial

BACKGROUND & AIMS

Lipid abnormalities are regarded as a risk factor for cardiovascular disease. Low vitamin D status has been shown to be associated with hyperlipidemia. We planned to research the effects of vitamin D supplementation as an adjuvant therapy for patients with hypercholesterolemia.

METHODS

Patients with hypercholesterolemia were enrolled in this single-center, double-blind, placebo-controlled trial in Beijing (39°54' N). Fifty-six patients were randomly assigned to receive vitamin D (n = 28, 2000 IU/d) or a placebo (n = 28) as an add-on to statin, by the method of permutated block randomization. Serum lipid levels were evaluated at baseline, 1, 3 and 6 months.

RESULTS

Vitamin D supplementation resulted in increased serum 25-hydroxyvitamin D concentrations compared with placebo (+16.3 ± 11.4 compared with +2.4 ± 7.1 ng/ml; p < 0.001). At 6 months, the primary end point, a difference in the fall of serum total cholesterol levels between the vitamin D and placebo groups after 6 months of treatment was significant -22.1 mg/dl (95% CI -32.3; -12.2) (p < 0.001). The difference between the groups in the fall of serum triglyceride levels after 6 months of treatment was -28.2 mg/dl (95% CI -48.8; -8.4) (p < 0.001). In patients with 25-hydroxyvitamin D level<30 ng/ml at baseline (n = 43), the serum total cholesterol and triglyceride levels were reduced by -28.5 ± 11.9 mg/dl (p < 0.001) and -37.1 ± 19.5 mg/dl (p < 0.001), respectively.

CONCLUSIONS

Vitamin D supplementation might improve serum lipid levels in statin-treated patients with hypercholesterolemia, it might be an adjuvant therapy for patients with hypercholesterolemia. Clinical Trials Registration Number - NCT02009787.

Vitamin D and nifedipine in the treatment of Chinese patients with grades I-II essential hypertension: a randomized placebo-controlled trial

OBJECTIVES

Low vitamin D status has been shown to be associated with hypertension. We planned to research the effect of vitamin D and nifedipine in the treatment of patients with essential hypertension.

METHODS

Patients with grades I-II essential hypertension were enrolled in this single-center, double-blind, placebo-controlled trial in Beijing. All patients received a conventional antihypertensive drug (nifedipine, 30 mg/d). One hundred and twenty-six patients were randomly assigned to receive vitamin D (n=63, 2000 IU/d) or a placebo (n=63) as an add-on to nifedipine, by the method of permutated block randomization. Ambulatory blood pressure monitoring was performed at baseline (month 0), at month 3 and at month 6.

RESULTS

In vitamin D supplementation group, there was a significant increase in mean 25-hydroxyvitamin D levels from baseline (19.4 ± 11.6 ng/ml) to 6 months (34.1 ± 12.2 ng/ml; p<0.001). At 6 months, the primary end points, a difference in the fall of 24-h mean blood pressure, between the groups was -6.2 mmHg (95% CI -11.2; -1.1) for systolic blood pressure (p<0.001) and -4.2 mmHg (95% CI -8.8; -0.3) for diastolic blood pressure (p<0.001) under intention to treat analysis. In patients with vitamin D <30 ng/ml at baseline (n=113), 24-h mean blood pressure decreased by 7.1/5.7 mmHg (p<0.001). Safety and tolerability were similar among the two groups.

CONCLUSIONS

Vitamin D supplementation can reduce blood pressure in patients with hypertension, it can be an adjuvant therapy for patients with grades I-II essential hypertension.

CLINICAL TRIAL REGISTRATION

This study was registered in the Chinese Clinical Trial Registry, it is available in Website: http://www.chictr.org/cn/;

REGISTRATION NUMBER

ChiCTR-ONC-13003840.