Intravenous Secondary hyperparathyroidism in patients with chronic kidney disease on dialysis
Adult: Initially, 5 mg 3 times weekly via IV bolus inj into the venous line of the dialysis circuit at the end of the haemodialysis session during rinse back or IV after rinse back. Dosage is individualised and titrated in increments of 2.5 mg or 5 mg at intervals of at least 4 weeks to obtain the desired PTH and serum Ca levels. Usual maintenance dose: 2.5-15 mg 3 times weekly. Max: 15 mg 3 times weekly. Dose reduction, dosing interruption or discontinuation may be required according to individual PTH and serum Ca levels (refer to detailed product guidelines). In patients switching from cinacalcet: Discontinue cinacalcet at least 7 days before initiation of etelcalcetide therapy.
Contraindications
Corrected serum Ca is below the lower limit of normal (LLN) range. Concomitant use with cinacalcet.
Special Precautions
Patient with heart failure, congenital long QT syndrome, history of QT interval prolongation, family history of long QT syndrome or sudden cardiac death, other conditions that predispose to QT interval prolongation and ventricular arrhythmia; history of seizure disorder, risk factors for upper gastrointestinal bleeding (e.g. gastritis, oesophagitis, ulcers, severe vomiting). Not recommended for use in patients with parathyroid carcinoma, primary hyperparathyroidism, or CKD who are not on dialysis. Pregnancy and lactation.
Adverse Reactions
Significant: Hypocalcaemia, worsening of heart failure which may be associated with hypocalcaemia (e.g. hypotension, CHF, decreased myocardial performance), adynamic bone disease, upper gastrointestinal bleeding; antibody development. Gastrointestinal disorders: Nausea, vomiting, diarrhoea. Immune system disorders: Hypersensitivity reactions, including anaphylaxis. Metabolism and nutrition disorders: Hypophosphataemia, hyperkalaemia. Musculoskeletal and connective tissue disorders: Muscle spasm, myalgia. Nervous system disorders: Headache, paraesthesia. Potentially Fatal: Severe adverse events associated with hypocalcaemia (e.g. seizures, QT interval prolongation, ventricular arrhythmia).
Monitoring Parameters
Ensure corrected serum Ca levels are at or above the LLN range before therapy initiation, during dose increase, or reinitiation of treatment after dosing interruption. Closely monitor serum Ca levels at baseline, 1 week after treatment initiation or dose adjustment, then every 4 weeks after maintenance dose is established; PTH levels at baseline, 4 weeks after treatment initiation or dose adjustment, then every 1-3 months thereafter; corrected serum Ca level and QT interval (in patients at risk of QT prolongation or ventricular arrhythmia). Assess for signs and symptoms of hypocalcaemia, gastrointestinal bleeding and ulceration, and worsening of heart failure or common gastrointestinal reactions (e.g. nausea, vomiting).
Overdosage
Symptoms: Hypocalcaemia with or without clinical symptoms. Management: Supportive treatment. Monitor serum Ca levels and for symptoms of hypocalcaemia.
Drug Interactions
Increased risk of hypocalcaemia with other agents known to reduce serum Ca levels (e.g. denosumab). Potentially Fatal: Concomitant use with cinacalcet may result in severe hypocalcaemia.
Action
Description: Mechanism of Action: Etelcalcetide is a synthetic peptide calcimimetic agent that allosterically binds to and activates the calcium-sensing receptor (CaSR) on the parathyroid gland, resulting in the reduction of parathyroid hormone (PTH) secretion and a decrease in serum Ca and phosphorus concentrations. Onset: Decreased PTH levels: Within 30 minutes. Pharmacokinetics: Absorption: Time to peak steady-state plasma concentration: 7-8 weeks (CKD patients). Distribution: Volume of distribution: Approx 796 L. Plasma protein binding: Mainly to albumin. Metabolism: Metabolised in the blood via reversible disulfide exchange with endogenous thiols to form conjugates with serum albumin. Excretion: CKD patients on haemodialysis: Via dialysate (approx 60%); urine (3.2%); faeces (4.5%). Elimination half-life: 3-4 days (CKD patients on haemodialysis).
Chemical Structure
Storage
Store between 2-8°C. Protect from light. Once removed from the refrigerator, use the vial within 7 days (if stored in original carton) or within 4 hours (if removed from original carton then protected from direct sunlight). Do not expose to temperatures >25°C.
H05BX04 - etelcalcetide ; Belongs to the class of other anti-parathyroid agents. Used in the management of calcium homeostasis.
References
Anon. Etelcalcetide. AHFS Clinical Drug Information [online]. Bethesda, MD. American Society of Health-System Pharmacists, Inc. https://www.ahfscdi.com. Accessed 17/07/2023.Anon. Etelcalcetide. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 17/07/2023.Buckingham R (ed). Etelcalcetide. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 17/07/2023.Joint Formulary Committee. Etelcalcetide. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 17/07/2023.Parsabiv 2.5 mg Solution for Injection (Amgen Limited). MHRA. https://products.mhra.gov.uk. Accessed 17/07/2023.Parsabiv 2.5 mg, 5 mg and 10 mg Solution for Injection (Amgen Biopharmaceuticals Malaysia Sdn Bhd). National Pharmaceutical Regulatory Agency - Ministry of Health Malaysia. https://www.npra.gov.my. Accessed 17/07/2023.Parsabiv Injection, Solution (Amgen Inc). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed. Accessed 17/07/2023.