Recommended Dosing of Cinacalcet for Elevated Parathyroid Hormone Levels
The recommended starting dose of cinacalcet is 30 mg once daily for patients with secondary hyperparathyroidism on dialysis, with titration every 2-4 weeks through sequential doses of 30,60,90,120, and 180 mg once daily to target iPTH levels of 150-300 pg/mL. 1
Dosing Guidelines by Condition
Secondary Hyperparathyroidism in CKD on Dialysis
- Initial dose: 30 mg once daily with food or shortly after a meal 1
- Titration: Increase dose no more frequently than every 2-4 weeks
- Sequential doses: 30,60,90,120, and 180 mg once daily
- Target iPTH: 150-300 pg/mL
- Administration: Take tablets whole, never chewed, crushed, or divided 1
Parathyroid Carcinoma and Primary Hyperparathyroidism
- Initial dose: 30 mg twice daily 1
- Titration: Every 2-4 weeks through sequential doses of 30 mg twice daily, 60 mg twice daily, 90 mg twice daily, and 90 mg 3-4 times daily
- Goal: Normalize serum calcium levels
Monitoring Parameters
Laboratory Monitoring
- Within 1 week of initiation/dose adjustment: Serum calcium and phosphorus 1
- 1-4 weeks after initiation/dose adjustment: iPTH
- Maintenance phase:
- Secondary hyperparathyroidism: Monthly serum calcium
- Parathyroid carcinoma/primary hyperparathyroidism: Calcium every 2 months
Hypocalcemia Management
- If calcium falls below 8.4 mg/dL but remains above 7.5 mg/dL:
- Increase calcium-containing phosphate binders
- Increase vitamin D sterols
- Provide supplemental calcium 1
- If calcium falls below 7.5 mg/dL or symptoms persist:
- Withhold cinacalcet until calcium reaches ≥8.0 mg/dL
- Restart at next lowest dose
Efficacy and Safety Considerations
Clinical Benefits
- Reduces risk of surgical parathyroidectomy by 51% (RR 0.49) 2
- Reduces risk of hypercalcemia (RR 0.23) 2
- Effectively sustains PTH reductions for up to 3 years 3
Limitations
- Little or no effect on all-cause mortality (RR 0.97) 4, 2
- Uncertain effects on cardiovascular mortality (RR 0.67) 4, 2
- Not indicated for CKD patients not on dialysis due to increased hypocalcemia risk 1
Adverse Effects
- Significantly increased risk of hypocalcemia (RR 7.38) 4
- Gastrointestinal effects: nausea (RR 2.05), vomiting (RR 1.95), diarrhea (RR 1.15) 4
- May increase QT interval 4
Important Clinical Considerations
Drug Interactions
- Strong CYP3A4 inhibitors may require dose adjustments 2
Contraindications
- Serum calcium below the lower limit of normal 1
Cautionary Notes
- Cinacalcet has become one of the largest single drug costs for dialysis patients despite limited mortality benefits 4, 2
- Benefits may be limited to preventing parathyroidectomy in patients for whom surgery is contraindicated 4
- Consider parathyroidectomy for tertiary hypercalcemic hyperparathyroidism not responsive to medical therapy 4
Cinacalcet should be considered as part of a treatment strategy that includes vitamin D sterols and phosphate binders, rather than as routine first-line therapy for all patients with elevated PTH levels.