Cinacalcet

PARATHYROID CARCINOMA AND PRIMARY HYPERPARATHYROIDISM (a separate indication with a DIFFERENT, twice-daily regimen — do not confuse with the once-daily secondary hyperparathyroidism dose above): the recommended starting dose for adults and elderly (>65 years) is 30 mg twice per day, titrated every 2 to 4 weeks through sequential doses of 30 mg twice daily, 60 mg twice daily, 90 mg twice daily, and 90 mg three or four times daily as necessary to reduce serum calcium concentration to or below the upper limit of normal. Serum calcium should be measured within 1 week after initiation or dose adjustment; once maintenance dose levels are established, every 2 to 3 months. After titration to the maximum dose, serum calcium should be periodically monitored and discontinuation considered if clinically relevant reductions in serum calcium are not maintained. PTH MONITORING (secondary hyperparathyroidism): PTH levels should be assessed at least 12 hours after dosing; measured 1 to 4 weeks after initiation or dose adjustment; and monitored approximately every 1-3 months during maintenance. Either intact PTH (iPTH) or biointact PTH (biPTH) may be used. Reference should be made to current treatment guidelines. SERUM CALCIUM: corrected serum calcium should be measured and should be at or above the lower limit of the normal range prior to the first dose. During titration monitor frequently and within 1 week of initiation or dose adjustment; once the maintenance dose is established, measure approximately monthly. If corrected serum calcium falls below 8.4 mg/dL (2.1 mmol/L) and above 7.5 mg/dL (1.9 mmol/L), or clinical symptoms of hypocalcaemia occur: calcium-containing phosphate binders, vitamin D sterols and/or adjustment of dialysis fluid calcium concentrations can be used to raise serum calcium according to clinical judgment. If the same range persists with symptoms despite attempts to increase serum calcium: reduce or withhold the cinacalcet dose. If corrected serum calcium is 7.5 mg/dL (1.9 mmol/L) or below, or symptoms persist and vitamin D cannot be increased: withhold cinacalcet until serum calcium reaches 8.0 mg/dL (2.0 mmol/L) and/or symptoms of hypocalcaemia have resolved, then reinitiate at the next lowest dose. SWITCH FROM ETELCALCETIDE: the switch and the appropriate washout period have not been studied; in patients who have discontinued etelcalcetide, cinacalcet should not be initiated until at least three subsequent haemodialysis sessions have been completed, at which time serum calcium should be measured and confirmed within the normal range before starting. HEPATIC IMPAIRMENT: no change in starting dose is necessary, but use with caution in moderate to severe hepatic impairment and monitor closely during titration and continued treatment. NOT FOR NON-DIALYSIS CKD: cinacalcet is not indicated for CKD patients not on dialysis — such patients have an increased risk of hypocalcaemia compared with cinacalcet-treated CKD patients on dialysis (§4.4). PAEDIATRIC (secondary hyperparathyroidism only; deliberately NOT expressed as a structured per-kg dose — see the hold note below): cinacalcet should only be initiated in children aged 3 years or older with ESRD on maintenance dialysis in whom secondary hyperparathyroidism is not adequately controlled with standard of care, and where serum calcium is in the upper range of, or above, the age-specified reference interval. The SPC states 'The recommended starting dose for children aged >= 3 years to < 18 years is <= 0.20 mg/kg once daily based on the patient's dry weight (see table 1)' — i.e. an UPPER BOUND that is then converted to a discrete banded starting dose in Table 1: dry weight 10 to <12.5 kg, starting dose 1 mg (sequential levels 1, 2.5, 5, 7.5, 10 and 15 mg); >=12.5 to <25 kg, 2.5 mg (2.5, 5, 7.5, 10, 15 and 30 mg); >=25 to <36 kg, 5 mg (5, 10, 15, 30 and 60 mg); >=36 to <50 kg, STARTING DOSE VALUE NOT PRESENT in the fetched table text — do not infer it (sequential levels 5, 10, 15, 30, 60 and 90 mg); >=50 to <75 kg, 10 mg (10, 15, 30, 60, 90 and 120 mg); >=75 kg, 15 mg (15, 30, 60, 90, 120 and 180 mg). The dose should be increased sequentially through available dose levels no more frequently than every 4 weeks, up to a maximum of 2.5 mg/kg/day and not exceeding a total daily dose of 180 mg. Paediatric dose adjustment on PTH: if iPTH is <150 pg/mL (15.9 pmol/L) and >=100 pg/mL (10.6 pmol/L), decrease to the next lower dose; if iPTH <100 pg/mL (10.6 pmol/L), stop and restart at the next lower dose once iPTH is >150 pg/mL (15.9 pmol/L); if stopped for more than 14 days, restart at the recommended starting dose. Paediatric dose adjustment on calcium: measure serum calcium within 1 week after initiation or dose adjustment, then weekly on maintenance; if corrected serum calcium is at or below the age-specified lower limit of normal, or symptoms of hypocalcaemia occur regardless of calcium level, stop cinacalcet and give calcium supplements, calcium-containing phosphate binders and/or vitamin D sterols as clinically indicated (measure corrected serum calcium within 5 to 7 days of stopping); restart at the next lower dose once calcium is above the age-specified lower limit and symptoms have resolved, at the recommended starting dose if stopped for more than 14 days, or at 1 mg/day if the patient was on the lowest dose (1 mg/day) before discontinuation. Children who require doses lower than 30 mg, or who are unable to swallow tablets, should receive cinacalcet granules. Safety and efficacy have NOT been established below 3 years of age for secondary hyperparathyroidism, and have NOT been established in children for parathyroid carcinoma or primary hyperparathyroidism (no data available). Verify any under-18 use against a children's formulary. PRIOR VERIFY HOLD — STATUS: an adversarial verification pass held this entry for two reasons. (1) STRUCTURED-FIELD: a previous draft set paedDose.dosePerKg = 0.2, which linearises an upper bound plus a banded table and over-doses every band (10 kg would compute 2 mg where Table 1 states 1 mg — a 2x overshoot; §4.4 records 'Life threatening events and fatal outcomes associated with hypocalcaemia have been reported in adult and paediatric patients', and the US label records a paediatric study halted after a fatality in a severely hypocalcaemic child). That finding is accepted and stands: paedDose is therefore null and the banded table is reproduced above in full. The >=36 to <50 kg starting dose is still missing from the fetched table text and must be read from the SPC. (2) SCOPE BLEED: the previous draft quoted the parathyroid carcinoma / primary hyperparathyroidism schedule from the US label while the eMC text for that indication was truncated. That is RESOLVED by the 2026-08-05 re-fetch — the schedule above is now quoted verbatim from eMC §4.2 (UK SPC), and the maxDose field is explicitly scoped per indication. SOURCE CAVEATS: SPC fetched is Cinacalcet 30 mg film-coated tablets (eMC product 11483); §4.4 and §4.8 are truncated at the source-fetch limit and §4.5 (interactions) was not retrieved.