Cinacalcet Research Articles

Trimethylamine N-Oxide and Cardiovascular Outcomes in Patients with ESKD Receiving Maintenance Hemodialysis.

Trimethylamine N-oxide (TMAO), a compound derived from byproducts of intestinal bacteria, has been shown to accelerate atherosclerosis in rodents. To date, there are conflicting data regarding the association of serum TMAO with cardiovascular outcomes in patients with ESKD, a population exhibiting both high serum TMAO and excessive atherosclerosis. We measured baseline serum TMAO concentrations in a subset of participants (n=1243) from the Evaluation of Cinacalcet Hydrochloride Therapy to Lower Cardiovascular Events (EVOLVE) trial and conducted post hoc analyses evaluating the association between baseline serum TMAO and cardiovascular outcomes. We observed a wide distribution of serum TMAO in our cohort, with approximately 80% of participants exhibiting TMAO concentrations ≥56 µM and a maximum TMAO concentration of 1103.1 µM. We found no association between TMAO and our primary outcome, a composite of cardiovascular mortality, myocardial infarction, peripheral vascular event, stroke, and hospitalization for unstable angina. Moreover, in unadjusted and adjusted analyses, we observed no relation between TMAO and all-cause mortality, the independent components of our composite outcome, or the original EVOLVE primary outcome. Although we did observe higher TMAO concentrations in white participants, further subgroup analyses did not confirm the previously identified interaction between TMAO and race observed in a prior study in patients receiving dialysis. We found no evidence linking TMAO to adverse clinical outcomes in patients receiving maintenance hemodialysis with moderate to severe secondary hyperparathyroidism.

Determination and Validation of HPTLC Method for Cinacalcet Hydrochloride

Cinacalcet Hydrochloride (CIN) is a new calcimimetic agent indicated for the use in hypercalcemia. The present work is aimed at development and validation of a novel and simple high-performance thin-layer chromatographic (HPTLC) method for the analysis of Cinacalcet Hydrochloride (active pharmaceutical ingredient, API. In the method, Aluminum-backed silica gel 60 F254 plates (10 × 10 cm) were used as stationary phase and chloroform: acetonitrile (6:4, v/v) as the mobile phase, which showed compact bands of Cinacalcet HCl (RF 0.30 ± 0.02). Quantitative analysis was carried out by densitometry at a wavelength of 282 nm. Linear regression analysis for the calibration spots showed good correlation ship with regression co-efficient r2 = 0.9994 in the range of 40 - 160 ng/band. The developed method suitability for quantification of CIN was learned by validating it as per the ICH guidelines. CIN detection limit was 0.48 ng/band and the quantification limit was 1.59 ng/band. The proposed method was found to be linear (r2 = 0.999), precise (%RSD < 2% for intraday and intermediate precision), accurate, specific, and robust. Further, the developed method was validated and found suitable for stress induced studies, since presence of degradants has no effect on CIN estimation. The proposed method was found to be simple, sensitive, precise, accurate and reproducible for the estimation of CIN.

Pharmacological and clinical profiles of a novel calcimimetic, evocalcet (ORKEDIA®)

Calcimimetics allosterically activate the calcium receptor (CaR) and inhibit the secretion of parathyroid hormone (PTH). Cinacalcet hydrochloride (cinacalcet) has been approved as the first calcimimetic drug for the treatment of secondary hyperparathyroidism (SHPT) in patients with hemodialysis. Cinacalcet improved the achievement of target serum PTH and Ca levels and helped drastically reduce the number of parathyroidectomies. However, cinacalcet has side effects involving the gastrointestinal tract, such as nausea and vomiting, which makes it difficult to increase the dose and may result in reduced compliance. Evocalcet has been developed to improve defects of cinacalcet for management of SHPT. Evocalcet acts as an allosteric modulator of CaR, just like cinacalcet. However, its metabolic pathway is different from that of cinacalcet. The metabolism of evocalcet by cytochrome P450 is very low, so evocalcet has higher bioavailability. As a result, its pharmacologically effective dose for the inhibition of PTH secretion is lower than that of cinacalcet. Evocalcet had less of an effect on the gastrointestinal tract than cinacalcet because of the reduced dose required. In a clinical trial with a randomized, double-blind, head-to-head comparison study, it was also confirmed that the incidence of gastrointestinal-related adverse events was lower in the evocalcet group than in the cinacalcet group. Evocalcet may thus be a potent option for the management of SHPT.

Surgical and medical treatment with cinacalcet in tertiary hyperparathyroidism

Tertiary hyperparathyroidism is commonly observed in patients with long-standing chronic kidney disease (CKD) after renal transplantation and is characterized by the autonomous hypersecretion of PTH leading to hypercalcemia. The primary treatment is surgery. After the introduction of cinacalcet, both surgical and medical methods have been commonly performed to treat tertiary hyperparathyroidism. However, which treatment is more appropriate has not been fully demonstrated. In this paper, the author will systematically review the related research of surgical treatment and cinacalcet in the treatment of 3HPT, and summarize their respective therapeutic effects. Key words: Surgical procedures, operative; Recurrent; Treatment outcome; Tertiary hyperparathyroidism

Performance of new 400‐MHz HTS power‐driven magnet NMR technology on typical pharmaceutical API, cinacalcet HCl

Performance of new 400‐MHz HTS power‐driven magnet NMR technology on typical pharmaceutical API, cinacalcet HCl

Structure elucidation capabilities on typical pharmaceutical drugs by new nuclear magnetic resonance technology: a 400 MHz high-temperature superconducting power-driven magnet NMR system

Nuclear magnetic resonance (NMR) is a powerful technique for the structure elucidation of organic molecules and significantly important in the pharmaceutical industry supporting the discovery and development of drug substances or active pharmaceutical ingredients (APIs). Following an initial study and assessment of a prototype NMR instrument with a high-temperature superconducting (HTS) power-driven magnet of 9.4 T (400 MHz for 1H observation) operating with standard commercial electronics and probes, we tested the instrument with three compounds representing typical pharmaceutical drugs. We compared results from two probes and shimstacks with different geometries (broadband fluorine observe (BBFO) with Bruker orthogonal shim system-3 (BOSS3) and Bruker quattro nucleus probe (QNP) with BOSS1 shims) testing standard one-dimensional (1D) NMR experiments including selective excitation experiments, and two-dimensional (2D) homonuclear and heteronuclear experiments for the purposes of evaluating the equipment for structure elucidation capabilities. In our initial study on cinacalcet HCl, only the 1D 1H experiment showed a loss of resolution when using the longer coiled BBFO probe with the BOSS3 shims compared to the shorter coiled QNP probe with BOSS1 shims. The selective excitation experiments using the cinacalcet HCl were successful. Our characterization of 1D (1H, 13C, 19F) and 2D (1H-1H and 1H-13C) NMR experiments for compounds I and II with the two probes and shimstacks indicated no significance differences. Overall, these results are satisfactory with the HTS magnet at the field of 9.4 T for the structural elucidation work of standard pharmaceutical compounds. This new technology has the advantage of being able to locate the HTS NMR magnet system in any chemistry or analytical laboratory where the samples are produced, facilitating rapid analysis with minor needs from the facilities and without cryogenic liquids.

Effectiveness of cinacalcet in combination with calcitriol for secondary hyperparathyroidism in patients with maintenance hemodialysis

One hundred and twenty maintenance hemodialysis patients with secondary hyperparathyroidism were randomly assigned to receive cinacalce, calcitriol or combination of cinacalce and cacitriol for treatment, with 40 cases in each group. Patients were followed up for 12 months; and the blood tests, echocardiography, examinations for osteoporosis and soft tissue calcification were performed every month. After 3 months of treatment, the serum levels of parathyroid hormone were decreased in all three groups (P<0.01); while the parathyroid hormone decreased more markedly with less influence on serum calcium and phosphorus levels in combination group. There were no significant changes in alkaline phosphatase, osteoporosis and cardiac valve calcification after treatment, compared with before treatment. There were no cases of hypercalcemia and hypocalcemia appearing in combination group after treatment. The study indicates that the combination of cinacalcet with calcitriol has better therapeutic effect for treatment of secondary hyperparathyroidism in maintenance dialysis patients. Key words: Hemodialysis; Secondary hyperparathyroidism; Cinacalcet; Calcitriol

Are oxyphil cells responsible for the ineffectiveness of cinacalcet hydrochloride in haemodialysis patients?

Parathyroid glands consist primarily of chief cells. In some cases, the proportion of parathyroid oxyphil cells increases in patients with chronic kidney disease. We describe a case of secondary hyperparathyroidism (SHPT) in a patient treated with haemodialysis who initially received large doses of vitamin D and calcium (Ca) supplements, as well as high doses of cinacalcet hydrochloride (C-HCl), but without any effect on parathyroid hormone levels. Following a successful parathyroidectomy, histopathological examination revealed that two of the parathyroid glands consisted of 40% of oxyphil cells. Oxyphil cells have significantly more Ca-sensing receptors (CaSRs) than chief cells, suggesting that CaSRs are involved in the transdifferentiation of chief cells to oxyphil cells. C-HCl treatment leads to a significant increase in parathyroid oxyphil cell content. This case suggests that C-HCl may induce specific phenotypic alterations in hyperplastic parathyroid glands in patients with severe SHPT.

Clinical efficacy of cinacalciclovir hydrochloride combined with low-dose calcitriol in the treatment of patients with secondary hyperparathyroidism of end stage renal disease

Objective To investigate the effect of cinacalcet combined with low-dose calcitriol in the treatment of patients with secondary hyperparathyroidism of end-stage renal disease. Methods A prospective analysis was conducted in 129 patients with end-stage renal disease and secondary hyperparathyroidism from April 2015 to August 2017 in the Department of Nephrology of Integrative Medicine Hospital of Wenzhou City, Zhejiang Province.The patients were randomly divided into 3 groups: group A received cinacalcet, group B received calcitriol, group C received cinacalcet and low-dose calcitriol for 3 months, respectively.Before and after treatment, the levels of serum phosphorus and serum calcium in the three groups were measured.The levels of parathyroid hormone and the parathyroid hormone clearance rate were measured to find out the therapeutic effect. Results The levels of serum calcium, phosphorus and total parathyroid hormone in group A were significantly lower than those before treatment(t=3.269, 2.263, 4.233, all P 0.05). The total parathyroid hormone level: group B> group A > group C, the whole parathyroid hormone clearance rate: group C > group A > group B, the differences were statistically significant(t=3.642, 3.263, all P group C> group A, the serum phosphorus level among the three groups after treatment had statistically significant difference, group B> group A > group C (t=3.265, 3.332, all P<0.05). Conclusion The combined use of cinacalcet and low-dose calcitriol in the treatment of secondary hyperparathyroidism in patients with end-stage renal disease can significantly reduce the level of parathyroid hormone and serum phosphorus, and without affecting serum calcium concentration. Key words: Hyperparathyroidism; Kidner disease; Calcitriol; Sillocaine; Phosphorus; Calcium

Chiral capillary zone electrophoresis in enantioseparation and analysis of cinacalcet impurities: Use of Quality by Design principles in method development

A capillary electrophoresis method for the simultaneous determination of the enantiomeric purity and of impurities of the chiral calcimimetic drug cinacalcet hydrochloride has been developed following Quality by Design principles. The scouting phase was aimed to select the separation operative mode and to identify a suitable chiral selector. Among the tested cyclodextrins, (2-carboxyethyl)-β-cyclodextrin and (2-hydroxypropyl)-γ-cyclodextrin (HPγCyD) showed good chiral resolving capabilities. The selected separation system was solvent-modified capillary zone electrophoresis with the addition of HPγCyD and methanol. Voltage, buffer pH, methanol concentration and HPγCyD concentration were investigated as critical method parameters by a multivariate strategy. Critical method attributes were represented by enantioresolution and analysis time. A Box-Behnken Design allowed the contour plots to be drawn and quadratic and interaction effects to be highlighted. The Method Operable Design Region (MODR) was identified by applying Monte-Carlo simulations and corresponded to the multidimensional zone where both the critical method attributes fulfilled the requirements with a desired probability π≥90%. The working conditions, with the MODR limits, corresponded to the following: capillary length, 48.5cm; temperature, 18°C; voltage, 26kV (26–27kV); background electrolyte, 150mM phosphate buffer pH 2.70 (2.60–2.80), 3.1mM (3.0–3.5mM) HPγCyD; 2.00% (0.00–8.40%) v/v methanol. Robustness testing was carried out by a Plackett-Burman matrix and finally a method control strategy was defined. The complete separation of the analytes was obtained in about 10min. The method was validated following the International Council for Harmonisation guidelines and was applied for the analysis of a real sample of cinacalcet hydrochloride tablets.

Angiotensin-related genetic determinants of cardiovascular disease in patients undergoing hemodialysis.

Cardiovascular mortality in patients receiving dialysis remains unacceptably high, with unexplained ancestry differences suggesting a genetic component. We analyzed DNA samples from 37% of subjects enrolled in the EValuation Of Cinacalcet Hydrochloride (HCl) Therapy to Lower CardioVascular Events (EVOLVE) trial, a randomized trial conducted in patients receiving hemodialysis with secondary hyperparathyroidism, comparing cinacalcet to placebo on a background of usual care. DNA was analyzed for single-nucleotide polymorphisms (SNPs) in the genes encoding the angiotensin-converting enzyme receptor type I (AGTR1) and angiotensin-converting enzyme (ACE). Survival analyses were conducted separately in European Ancestry (EA) and African Ancestry (AfAn) due to known differences in cardiovascular events, minor alleles for the same variant and the frequency of minor alleles. Our primary determination was a meta-analysis across both races. Meta-analysis showed significant associations between rs5186 in AGTR1 and increased rates by 25-34% for the primary endpoint (composite of death or nonfatal myocardial infarction, hospitalization for unstable angina, heart failure or peripheral vascular event), all-cause mortality, cardiovascular mortality and heart failure; all P < 0.001. Three correlated SNPs in ACE were associated with lower rates of sudden cardiac death (SCD) in EA samples. One ACE SNP, rs4318, only found in the AfAn samples, was associated with a lower rate of SCD in the AfAn samples. The C allele in rs5186 in AGTR1 was associated with higher rates of death and major cardiovascular events in a meta-analysis of EA and AfAn patients with end-stage kidney disease. SNPs in ACE were associated with SCD.

Performance of new 400-MHz HTS power-driven magnet NMR technology on typical pharmaceutical API, cinacalcet HCl.

After years towards higher field strength magnets, nuclear magnetic resonance (NMR) technology in commercial instruments in the past decade has expanded at low and high magnetic fields to take advantage of new opportunities. At lower field strengths, permanent magnets are well established, whereas for midrange and high field, developments utilize superconducting magnets cooled with cryogenic liquids. Recently, the desire to locate NMR spectrometers in nontypical NMR laboratories has created interest in the development of cryogen-free magnets. These magnets require no cryogenic maintenance, eliminating routine filling and large cryogen dewars in the facility. Risks of spontaneous quenches and safety concerns when working with cryogenic liquids are eliminated. The highest field commercially available cryogen-free NMR magnet previously reported was at 4.7T in 2013. Here we tested a prototype cryogen-free 9.4-T power-driven high-temperature-superconducting (HTS) magnet mated to commercial NMR spectrometer electronics. We chose cinacalcet HCl, a typical active pharmaceutical ingredient, to evaluate its performance towards structure elucidation. Satisfactory standard 1D and 2D homonuclear and heteronuclear NMR results were obtained and compared with those from a standard 9.4-T cryogenically cooled superconducting NMR instrument. The results were similar between both systems with minor differences. Further comparison with different shims and probes in the HTS magnet system confirmed that the magnet homogeneity profile could be matched with commercially available NMR equipment for optimal results. We conclude that HTS magnet technology works well providing results comparable with those of standard instruments, leading us to investigate additional applications for this magnet technology outside a traditional NMR facility.

A case of hyperparathyroidism-associated parkinsonism successfully treated with cinacalcet hydrochloride, a calcimimetic

BackgroundSome metabolic disorders, including abnormal calcium metabolism, can develop and worsen parkinsonism. However, whether hyperparathyroidism can cause parkinsonism remains controversial.Case presentationAn 83-year-old woman with a history of right thalamic hemorrhage and drug-induced parkinsonism, was admitted due to worsening of parkinsonian symptoms including mask-like face, bradykinesia, freezing of gait, and rigidity. She had been diagnosed with autoimmune hepatitis and was being treated with prednisolone. Examinations revealed hypercalcemia (14.3 mg/dL) with an increased level of intact parathyroid hormone (iPTH) (361 pg/mL). Her symptoms were resistant to some additional anti-parkinsonian drugs; however, cinacalcet hydrochloride, a calcimimetic for the treatment of secondary hyperparathyroidism, normalized levels of serum calcium and iPTH, and remarkably improved her symptoms.ConclusionsIn the present case, we speculate that hypercalcemia probably due to secondary hyperparathyroidism that had developed during steroid therapy deteriorated the parkinsonism.

Discovery of evocalcet, a next-generation calcium-sensing receptor agonist for the treatment of hyperparathyroidism

The calcium-sensing receptor (CaSR) plays an important role in sensing extracellular calcium ions and regulating parathyroid hormone secretion by parathyroid gland cells, and the receptor is a suitable target for the treatment of hyperparathyroidism. Cinacalcet hydrochloride is a representative CaSR agonist which widely used for the hyperparathyroidism. However, it has several issues to clinical use, such as nausea/vomiting and strong inhibition of CYP2D6. We tried to improve these issues of cinacalcet for a new pharmaceutical agent as a preferable CaSR agonist. Optimization from cinacalcet resulted in the identification of pyrrolidine compounds and successfully led to the discovery of evocalcet as an oral allosteric CaSR agonist. Evocalcet, which exhibited highly favorable profiles such as CaSR agonistic activity and good DMPK profiles, will provide a novel therapeutic option for secondary hyperparathyroidism.

A novel calcimimetic agent, evocalcet (MT-4580/KHK7580), suppresses the parathyroid cell function with little effect on the gastrointestinal tract or CYP isozymes in vivo and in vitro.

Cinacalcet hydrochloride (cinacalcet), an oral calcimimetic agent has been widely used for the management of secondary hyperparathyroidism (SHPT) in chronic kidney disease (CKD). In sharp contrast to vitamin D receptor activators, cinacalcet suppresses SHPT without inducing hypercalcemia or hyperphosphatemia. Nevertheless, some patients remain refractory to SHPT with this agent, as the dose cannot be sufficiently increased due to gastrointestinal symptoms. In order to resolve this issue, we have developed a newly synthesized calcimimetic agent, evocalcet (MT-4580/KHK7580). In a rat model of CKD induced by 5/6 nephrectomy, oral administration of evocalcet efficiently suppressed the secretion of parathyroid hormone (PTH). With regard to the gastro-intestinal effects, cinacalcet induced a significant delay in gastric emptying in rats, while evocalcet did no marked effects on it. Evocalcet also demonstrated the less induction of emesis compared to cinacalcet in common marmosets. The pharmacological effects of evocalcet were observed at lower doses because of its higher bioavailability than cinacalcet, which may have contributed to the reduced GI tract symptoms. In addition, evocalcet showed no substantial direct inhibition of any CYP isozymes in in vitro liver microsome assay, suggesting a better profile in drug interactions than cinacalcet that inhibits cytochrome P450 (CYP) 2D6. These findings suggest that evocalcet can be a better alternative to cinacalcet, an oral calcimimetic agent, with a wider safety margin.

16 Immobilization Related Hypercalcemia Resistant to Denosumab but Responsive to Cinacalcet

16 Immobilization Related Hypercalcemia Resistant to Denosumab but Responsive to Cinacalcet

Incidence, predictors and therapeutic consequences of hypocalcemia in patients treated with cinacalcet in the EVOLVE trial

The calcimimetic cinacalcet is used to treat secondary hyperparathyroidism in patients receiving dialysis, and asymptomatic hypocalcemia is often observed following its initiation. Here we investigated the incidence, predictors and therapeutic consequences of hypocalcemia by a post hoc analysis of the randomized, double-blind, placebo-controlled EValuation Of Cinacalcet Hydrochloride Therapy to Lower CardioVascular Events (EVOLVE) trial. Hypocalcemia was classified as mild (total serum calcium 8.0-8.39 mg/dL), moderate (7.5-7.99 mg/dL) or severe (under 7.5 mg/dL). At least one episode of hypocalcemia developed within 16 weeks after the first administered dose among 58.3% of 1938 patients randomized to cinacalcet versus 14.9% of 1923 patients randomized to placebo. Hypocalcemia in the cinacalcet group was severe in 18.4% of the patients versus 4.4% in the placebo group. Severe hypocalcemia following administration of cinacalcet was associated with higher baseline plasma parathyroid hormone, lower corrected total serum calcium, higher serum alkaline phosphatase, geographic region (patients from Latin America and Russia had a higher risk relative to the United States) and higher body mass index. The median cinacalcet dose immediately prior to the first hypocalcemic episode was 54-58 mg/day and similar in the three hypocalcemia categories. In the majority of patients, hypocalcemia resolved spontaneously within 14 days without modification of background therapy. Among patients who received an intervention, the most common was an increase in the active vitamin D sterol dose. Thus, the occurrence of hypocalcemia is frequent following initiation of cinacalcet and the likelihood of developing hypocalcemia was related to the severity of secondary hyperparathyroidism. Hypocalcemia was generally asymptomatic and self-limited.

Targeted surgical parathyroidectomy in end-stage renal disease patients and long-term metabolic control: A single-center experience in the current era.

The long-term results of surgical parathyroidectomy (PTX) in end-stage renal disease (ESRD) patients are less well known in the modern era of newer activated vitamin-D analogs, calcimimetics and intraoperative monitoring of parathyroid hormone (PTH). We performed a retrospective chart review of all ESRD patients undergoing PTX at the University of Mississippi Medical Center between January 2005 and August 2011, with follow-up data as available up to 4 years. All PTXs were performed with intraoperative second-generation PTH monitoring and targeted gland size reduction. The cohort (N = 37) was relatively young with a mean (±SD) age of 48.4 ± 13.9. 94.6% of the subjects were African American and 59.5% female. Preoperatively, 45.9% received cinacalcet (CNC) at a mean dose of 63.5 ± 20.9 mg. The size of the largest removed glands measured 1.7 ± 0.8 cm and almost all (94.6%) glands had hyperplasia on histology. The mean length of inpatient stay was 5.5 ± 2.4 days. Preoperative calcium/phosphorus measured 9.6 ± 1.2/6.6 ± 1.7 mg/dL with PTH concentrations of 1589 ± 827 pg/mL. Postoperative PTH values measured 145.4 ± 119.2 pg/mL. Preoperative PTH strongly correlated (P < 0.0001) with both alkaline phosphatase (ALP) levels (r: 0.596) and the number of inpatient days (r: 0.545), but not with CNC administration. Independent predictors for the duration of hospitalization were preoperative ALP (beta 0.469; P = 0.001) and age (beta -0.401; P = 0.005) (R2 0.45); for postoperative hypocalcemia, age (beta: -0.321; P = 0.006) and preoperative PTH (beta: 0.431; P = 0.036) were significant in linear regression models with stepwise selection. Gland-sparing PTX achieved acceptable control of ESRD-associated hyperparathyroidism in most patients from a socioeconomically challenged, underserved population of the United States.

Synthesis of Cinacalcet Hydrochloride: A Case Study on the Impact of Agitation Speed on the Reaction Kinetics of Schiff’s Base during Scale-up

During the process development of Cinacalcet hydrochloride, a calcimimetic agent, we encountered an unexpected substantial increase in the content of impurities in the product while scaling up the process in the pilot plant. Detailed investigation led to the conclusion that the agitation speed of the reaction mass impacted the reaction kinetics of Schiff’s base, leading to the formation of the impurities and lowering the product yield to ca. 40%. The present work reports details of an investigation carried out to control the formation of impurities to achieve an efficient and one-pot process for Cinacalcet hydrochloride with an overall yield of ca. 70%.

The Calcium-Sensing Receptor Gene Polymorphism rs1801725 and Calcium-Related Phenotypes in Hemodialysis Patients

Background/Aims: The calcium-sensing receptor gene (CASR) rs1801725 variant is responsible for a non-conservative amino-acid change (A986S) in the calcium-sensing receptor cytoplasmic tail. We hypothesized that rs1801725 polymorphism might be helpful in understanding Ca-related abnormalities in HD patients. Methods: In 1215 subjects (245 on cinacalcet), we determined the associations of rs1801725 with secondary hyperparathyroidism (sHPT)-related laboratory parameters, PTH-decreasing effect of cinacalcet hydrochloride, coronary artery disease (CAD), myocardial infarction (MI), nephrolithiasis-related ESRD, and mortality. CASR rs7652589(A<G)_rs1801725(G>T) haplotypes and rs1801725 epistatic interactions with vitamin D signaling pathway genes were examined for associations with selected phenotypes. Results: The rs1801725 variant allele showed an increasing independent effect on plasma PTH (P_corrected = 0.009). CASR rs7652589_rs1801725 AT haplotype was associated with 1.7-fold higher frequency of PTH levels over 437 pg/mL than the reference haplotype GG (P = 0.001). CASR rs7652589_rs1801725 AG haplotype was 1.5-fold more frequent in nephrolithiasis-related ESRD than the GG haplotype (P = 0.004). There were no significant associations between rs1801725, CAD, MI, and response to cinacalcet. Variant homozygosity of rs1801725 correlated independently with higher infection-related mortality compared with heterozygosity (HR 7.95, 95%CI 2.15 – 29.37, P = 0.003) and major homozygosity (HR 5.89, 95%CI 1.69 – 20.55, P = 0.040). CASR rs1801725 did not show epistatic interactions with vitamin D signaling pathway genes concerning tested associations. Conclusion: The variant allele of CASR rs1801725 solely and together with the variant allele of rs7652589 increases risk of more advanced sHPT. Homozygosity of the rs1801725 variant allele contributes to infection-related mortality in HD patients.