A Single- and Multiple-Dose, Multicenter Study of Etelcalcetide in Japanese Hemodialysis Patients With Secondary Hyperparathyroidism

Calcimimetics treatment strategy for serum calcium and phosphate management in patients with secondary hyperparathyroidism undergoing dialysis: A systematic review and meta-analysis of randomized studies

INTRODUCTION

Several calcimimetics, other than cinacalcet, are commercially available; however, their effects on calcium and phosphate levels have not yet been fully studied. We conducted a systematic review and meta-analysis of randomized controlled trials to evaluate the impact of calcimimetics on the management of serum calcium and phosphate levels in patients with secondary hyperparathyroidism undergoing dialysis.

METHODS

A systematic literature search through October 2023 and a meta-analysis were conducted on the effects of upacicalcet, etelcalcetide, evocalcet, and cinacalcet on serum calcium and phosphate levels in patients with secondary hyperparathyroidism undergoing dialysis; we searched PubMed, Ovid MEDLINE, and the Cochrane Central Register of Controlled Trials, and 21 studies comprising 6371 patients undergoing dialysis were included.

RESULTS

Participants treated with calcimimetics had lower serum calcium and phosphate levels than placebo.

CONCLUSION

Calcimimetics significantly reduced serum calcium and phosphate levels compared to placebo in patients with secondary hyperparathyroidism undergoing dialysis, independent of therapeutic strategy or concomitant vitamin D treatment.

Phase 2 study of upacicalcet in Japanese haemodialysis patients with secondary hyperparathyroidism: an intraindividual dose-adjustment study

Background

Upacicalcet is a novel small-molecule calcimimetic agent developed for intravenous injection. Here, we evaluated the long-term efficacy and safety of upacicalcet treatment via intraindividual dose adjustment in haemodialysis patients with secondary hyperparathyroidism (SHPT).

Methods

A phase 2, multicentre, open-label, single-arm study was conducted. Upacicalcet was administered for 52 weeks; the starting dose was 50 μg thrice a week, and then adjusted to 25, 50, 100, 150, 200, 250, or 300 μg, according to the dose-adjustment method set in the protocol. The primary endpoint was the percentage of patients with serum intact parathyroid hormone (iPTH) level achieving a target range of 60-240 pg/mL (target achievement rate) at week 18.

Results

A total of 58 patients were administered upacicalcet. The target achievement rate of serum iPTH level at week 18 was 57.9%, which increased to 80.8% at week 52. The serum-corrected calcium (cCa) level decreased immediately after upacicalcet administration, but no further decrease was observed. Adverse events were observed in 94.8% of patients, and adverse drug reactions (ADRs) occurred in 20.7% of patients. The most common ADR was decreased adjusted calcium in eight patients; dizziness occurred as a serious ADR in one patient. The serum cCa level of patients who interrupted upacicalcet treatment at a serum cCa level of <7.5 mg/dL recovered to ≥7.5 mg/dL immediately after the interruption.

Conclusions

In haemodialysis patients with SHPT, upacicalcet doses of 25-300 μg for 52 weeks were found to be highly effective and well-tolerated, with minor safety concerns.

A Systematic Review and Meta-analysis of Efficacy and Safety of Calcimimetic Agents in the Treatment of Secondary Hyperparathyroidism in Patients with Chronic Kidney Disease

BACKGROUND

Some reports have pointed out that calcimimetics agents are effective in the treatment of secondary hyperparathyroidism (SHPT) in chronic kidney disease (CKD) patients, but there is no detailed description of the advantages and disadvantages of calcimimetics agents of SHPT in CKD patients. We tried to pool the published data to verify the effectiveness of calcimimetics agents and to compare the advantages and disadvantages of cinacalcet compared with control in the treatment of SHPT in CKD patients.

METHODS

We included eligible studies of published papers from January 1st, 2000 to December 31st, 2020 in Medline, Pubmed and Web of science databases, and the data were extracted for this meta-analysis.

RESULTS

Twenty-seven studies were eligible, and all the included studies were randomized controlled trials (RCT) including patients treated with long-term dialysis. The results indicated that calcimimetic agents can reduce the parathyroid hormone (PTH, pg/ml) level (WMD = -178.22, 95% CI: -238.57, -117.86, P < 0.00001), calcium (Ca, mg/dl) level (WMD = -0.71, 95% CI: -0.86, -0.55, P < 0.00001), phosphorus (P, mg/dl) level (WMD = -0.32, 95% CI: -0.55, -0.08, P = 0.008), calcium-phosphorus product level (WMD = -7.73, 95% CI: -9.64, -5.82, P < 0.00001). Calcimimetic agents increased the bone alkaline phosphatase (BSAP, ng/ml) levels and rate of achieving target PTH, and reduced osteocalcin levels and the rate of parathyroidectomy. Calcimimetic agents increased the total adverse events' rate, the rate of hypocalcemia and gastrointestinal side effects (nausea, vomiting, abdominal pain and diarrhea), but there was no significant difference in serious adverse events between the calcimimetic agent group and control group.

CONCLUSION

Calcimimetic agents can reduce the PTH level, Ca level, P level, calcium-phosphorus product level and do not increase serious adverse events.

A Phase I, Multiple-Dose, Randomized, Double-Blind, Placebo-Controlled Study to Evaluate Pharmacokinetics, Safety, and Tolerability of Etelcalcetide Administered Intravenously to Chinese Patients With Chronic Kidney Disease Undergoing Hemodialysis

PURPOSE

This study reports data from the first evaluation of etelcalcetide treatment in Chinese adults with chronic kidney disease and secondary hyperparathyroidism.

METHODS

This phase I, randomized study compared thrice-weekly etelcalcetide (5 mg per dose intravenously) and placebo in 33 Chinese adults (aged 18-70 years) receiving hemodialysis. Patients in both treatment groups received standard-of-care treatment with a total of 12 doses of the investigational product during a 4-week treatment period, followed by 4 weeks of washout and follow-up. Pharmacokinetic (PK) parameters (primary endpoint), tolerability (secondary endpoint), and changes in intact parathyroid hormone (iPTH) and corrected calcium (cCa) concentrations (exploratory endpoints) were assessed. PK parameters, ie, the maximum plasma concentration (C_max) and area under the plasma concentration-time curve (AUC_0-last), assessed over the interdialytic interval following the first and last doses were evaluated. The incidence of treatment-emergent adverse events (AEs) and anti-etelcalcetide antibodies was assessed.

FINDINGS

Etelcalcetide administered to 25 patients was compared with placebo administered to 8 patients. Etelcalcetide exposure, assessed by C_max and AUC_0-last, increased after multiple-dose administration of etelcalcetide through day 27, with a mean (SD) accumulation ratio of 3.02 (0.61) based on AUC. At least one AE was reported for all patients in the etelcalcetide group and for 87.5% of patients in the placebo group. Serious AEs were reported in 12% of patients in the etelcalcetide group only. No deaths occurred, and a single discontinuation because of patient withdrawal of consent was reported in the etelcalcetide group. Preexisting anti-etelcalcetide antibodies were detected in one patient. The mean serum cCa level for all patients was maintained at >1.75 mmol/L. The iPTH and cCa concentrations decreased as expected, and a maximum mean decrease from baseline of 35.13% in iPTH levels was detected on day 27.

IMPLICATIONS

Multiple doses of 5 mg etelcalcetide were well tolerated, and observed etelcalcetide PK and safety profiles were similar to those in reports in adults of ethnicities other than Chinese. Changes in serum iPTH and serum calcium levels were consistent with expected responses to etelcalcetide. ClinicalTrials.gov identifier: NCT03283098.

Phase 1, single-dose study to assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of etelcalcetide in pediatric patients with secondary hyperparathyroidism receiving hemodialysis

BACKGROUND

Data on the safety, efficacy of etelcalcetide in children with secondary hyperparathyroidism (sHPT) are limited.

METHODS

This phase 1 study (NCT02833857) evaluated the safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD) of single-dose etelcalcetide (0.035 mg/kg intravenously) in pediatric hemodialysis patients (two cohorts; 1: 12-< 18 years; 2: 2-< 12 years). Treatment-emergent adverse events (AEs), PK/PD were assessed post-dose on D1 at 10 min and 4 h, on multiple days until D10, and at end of study (D30).

RESULTS

Etelcalcetide administered to 11 patients (mean [SD] age 10.3 [4.3] years; cohort 1, n = 6; cohort 2, n = 5) was well tolerated. AEs were consistent with established safety profiles in adults. Two patients (1 per cohort) reported treatment-related AEs (cohort 1: hypocalcemia; cohort 2: headache, paresthesia, vomiting). No serious AEs or deaths were reported. Mean serum corrected calcium (cCa) for all patients was maintained > 2.25 mmol/L. After etelcalcetide dosing, PK exposures declined, with mean C_max, AUC_last, and AUC_inf exposures higher in cohort 1. Median percent change in serum intact parathyroid hormone (iPTH) from baseline (cohort 1: 51.2 pmol/L; cohort 2: 84.0 pmol/L) reached the nadir on D1 at 4 h (cohort 1: - 33.4%; cohort 2: - 64.2%). Mean total calcium and cCa reached nadirs on D3 at 2.39 mmol/L, and ionized Ca on D1 at 4 h.

CONCLUSIONS

Single-dose etelcalcetide (0.035 mg/kg) was well tolerated with expected PK and safety profiles. Overall pattern of changes in serum iPTH and serum calcium was similar between cohorts and consistent with expected responses to etelcalcetide.

New Intravenous Calcimimetic Agents: New Options, New Problems. An Example on How Clinical, Economical and Ethical Considerations Affect Choice of Treatment

BACKGROUND

Dialysis treatment is improving, but several long-term problems remain unsolved, including metabolic bone disease linked to chronic kidney disease (CKD-MBD). The availability of new, efficacious but expensive drugs (intravenous calcimimetic agents) poses ethical problems, especially in the setting of budget limitations.

METHODS

Reasons of choice, side effects, biochemical trends were discussed in a cohort of 15 patients (13% of the dialysis population) who stared treatment with intravenous calcimimetics in a single center. All patients had previously been treated with oral calcimimetic agents; dialysis efficacy was at target in 14/15; hemodiafiltration was employed in 10/15. Median Charlson Comorbidity Index was 8. The indications were discussed according to the principlist ethics (beneficience, non maleficience, justice and autonomy). Biochemical results were analyzed to support the clinical-ethical choices.

RESULTS

In the context of a strict clinical and biochemical surveillance, the lack of side effects ensured "non-maleficence"; efficacy was at least similar to oral calcimimetic agents, but tolerance was better. Autonomy was respected through a shared decision-making model; all patients appreciated the reduction of the drug burden, and most acknowledged better control of their biochemical data. The ethical conflict resides in the balance between the clinical "beneficience, non-maleficience" advantage and "justice" (economic impact of treatment, potentially in attrition with other resources, since the drug is expensive and included in the dialysis bundle). The dilemma is more relevant when a patient's life expectancy is short (economic impact without clear clinical advantages), or when non-compliance is an issue (unclear advantage if the whole treatment is not correctly taken).

CONCLUSIONS

In a context of person-centered medicine, autonomy, beneficence and non-maleficence should weight more than economic justice. While ethical discussions are not aimed at finding "the right answer" but asking "the right questions", this example can raise awareness of the importance of including an ethical analysis in the choice of "economically relevant" drugs.

Evocalcet: A New Oral Calcimimetic for Dialysis Patients With Secondary Hyperparathyroidism

Patients with chronic kidney disease often develop secondary hyperparathyroidism (SHPT), marked by high levels of circulating parathyroid hormone (PTH) and increased risk of morbidity and mortality. Patients with SHPT are treated with a therapeutic combination that commonly includes calcimimetics, which have recently become popular in clinical settings, and other agents such as vitamin D preparations. Calcimimetics are a drug class that reduces PTH levels by targeting the calcium‐sensing receptor. Cinacalcet, a representative calcimimetic, is widely used; however, a high incidence of upper gastrointestinal (GI) tract‐related adverse events (AEs) can result in insufficient dosage and poor long‐term compliance. The newly approved evocalcet has equivalent efficacy to cinacalcet at a lower clinical dose, with improved bioavailability, fewer upper GI tract‐related AEs, and fewer safety concerns. This review gives an overview of calcimimetic agents, with a special focus on evocalcet, and describes the clinical advantages of evocalcet in the treatment of dialysis patients with SHPT.

Pharmacology of Parsabiv® (etelcalcetide, ONO-5163/AMG 416), a novel allosteric modulator of the calcium-sensing receptor, for secondary hyperparathyroidism in hemodialysis patients

Etelcalcetide hydrochloride (Parsabiv^®, ONO-5163/AMG 416) is an allosteric modulator of the calcium (Ca)-sensing receptor that was originally produced by KAI Pharmaceuticals Inc. (now Amgen Inc.). It has recently been approved as the first intravenous calcimimetic agent for secondary hyperparathyroidism (SHPT) in many countries. Etelcalcetide is an intravenous injectable drug that can be administered and eliminated through the dialysis circuit in chronic kidney disease patients. In the present study, we evaluated the in vitro pharmacological profile and in vivo parathyroid hormone (PTH)- and Ca-lowering activities of etelcalcetide in a rat 5/6 nephrectomy model of chronic renal insufficiency with SHPT. Etelcalcetide increased the intracellular Ca concentration in HEK-293T cells expressing human Ca-sensing receptor with an EC₅₀ value (95% confidence interval) of 0.53 μM (0.28-1.0 μM) and suppressed PTH secretion from rat parathyroid gland cells with 0.36 μM (0.24-0.54 μM) by activating Ca-sensing receptor. The specificity of etelcalcetide was evaluated by examining its ability to stimulate or inhibit radioligand binding to a panel of 34 off-target proteins. There were no significant changes in the presence of 10 μM etelcalcetide. Furthermore, in a rat 5/6 nephrectomy model of chronic renal insufficiency with SHPT, single intravenous administration of etelcalcetide at 0.3, 1.0, and 3.0 mg/kg decreased plasma PTH and serum Ca levels. Taken together, the present findings identify etelcalcetide as a calcimimetic with potent PTH- and Ca-lowering effects via Ca-sensing receptor agonist activity.

Treatment of secondary hyperparathyroidism in patients on hemodialysis using a novel synthetic peptide calcimimetic, etelcalcetide: a short-term clinical study

Objective

Secondary hyperparathyroidism (SHPT) is a major complication in patients with chronic kidney disease (CKD). SHPT is related to chronic kidney disease-mineral bone disorder, leading to increased morbidity and mortality. Etelcalcetide is intravenously administered at the end of hemodialysis (HD). Etelcalcetide differs from the oral calcimimetic cinacalcet because it reduces gastrointestinal adverse events, thereby improving therapeutic effects. Etelcalcetide has only been approved by the U.S. Food and Drug Administration for several months. Therefore, there have only been a few reports regarding treatment of SHPT using etelcalcetide. This study aimed to evaluate the efficacy of etelcalcetide in patients on HD with SHPT.

Methods

Nine patients on HD (four men and five women, aged 58 ± 10 years) were enrolled in this study. All of the patients received etelcalcetide (5–10 mg, three times a week after HD). The observation period was 4.4 ± 1.0 months.

Results

All of the patients showed a significant reduction in serum parathyroid hormone levels during the observation period (−59% ± 20%). No significant adverse effects were observed.

Conclusions

Although this study had an uncontrolled small group and a short observation period, our results suggest that etelcalcetide could be a promising agent for SHPT treatment.

Etelcalcetide (Parsabiv) for Secondary Hyperparathyroidism in Adults With Chronic Kidney Disease on Hemodialysis

Etelcalcetide (Parsabiv) for hyperparathyroidism in adults with chronic kidney disease on hemodialysis.

Clinical Pharmacokinetics and Pharmacodynamics of Etelcalcetide, a Novel Calcimimetic for Treatment of Secondary Hyperparathyroidism in Patients With Chronic Kidney Disease on Hemodialysis

Etelcalcetide, a d-amino acid peptide, is an intravenous calcimimetic approved for the treatment of secondary hyperparathyroidism. Etelcalcetide binds the calcium-sensing receptor and increases its sensitivity to extracellular calcium, thereby decreasing secretion of parathyroid hormone (PTH) by chief cells. Etelcalcetide and its low-molecular-weight transformation products are rapidly cleared by renal excretion in healthy subjects, but clearance is substantially reduced and dependent on hemodialysis in end-stage renal disease. The effective half-life is 3-5 days in patients undergoing hemodialysis 3 times a week. A clinical study using a single microtracer intravenous dose of [¹⁴ C]etelcalcetide indicated that 60% of the administered dose was eliminated in dialysate. Etelcalcetide undergoes reversible disulfide exchange with serum albumin to form a serum albumin peptide conjugate that is too large (67 kDa) to be dialyzed, until a subsequent exchange forms etelcalcetide or a low-molecular-weight transformation product. This exchange from albumin is apparent after hemodialysis, when it partially restores etelcalcetide concentrations in plasma. Etelcalcetide has no known risks for drug-drug interactions. In phase 3 studies, 74%-75% of hemodialysis patients with secondary hyperparathyroidism who received etelcalcetide achieved a >30% PTH reduction from baseline versus 8%-10% of patients who received placebo. The pharmacokinetics and pharmacodynamics of etelcalcetide in hemodialysis patients supports a 5-mg starting dose administered after hemodialysis and uptitration in 2.5- or 5-mg increments every 4 weeks to a maximum dose of 15 mg 3 times a week.

Managing hyperparathyroidism in hemodialysis: role of etelcalcetide

Secondary hyperparathyroidism (SHPT) is common in patients receiving maintenance hemodialysis and is associated with adverse outcomes. Currently, SHPT is managed by reducing circulating levels of phosphate with oral binders and parathyroid hormone (PTH) with vitamin D analogs and/or the calcimimetic cinacalcet. Etelcalcetide, a novel calcimimetic administered intravenously (IV) at the end of a hemodialysis treatment session, effectively reduces PTH in clinical trials when given thrice weekly. Additional clinical effects include reductions in circulating levels of phosphate and FGF-23 and an improved profile of markers of bone turnover. However, despite being administered IV, etelcalcetide appears to be associated with rates of nausea and vomiting comparable to those of cinacalcet. Additionally, etelcalcetide, relative to placebo, causes hypocalcemia and prolonged electrocardiographic QT intervals, effects that must be considered when contemplating its use. Etelcalcetide likely has a role in treating hemodialysis patients with uncontrolled SHPT or with hypercalcemia or hyperphosphatemia receiving activated vitamin D compounds. However, its use should be at least partially constrained by consideration of the risk of hypocalcemia and resultant prolonged QT intervals in vulnerable patients. Because of its effectiveness as a PTH-reducing agent administered in the dialysis unit, etelcalcetide represents a potentially promising new therapeutic approach to the often vexing problem of SHPT in hemodialysis patients. However, whether its use is associated with changes in surrogate clinical end points, such as effects on rates of parathyroidectomy, fracture, vascular calcification, or mortality or on quality of life, remains to be studied.