From the Guidelines
The management of secondary hyperparathyroidism (SHPT) should prioritize a multi-step approach, including medical management with phosphate binders, vitamin D analogs, and calcimimetics, and surgical intervention with total parathyroidectomy (TPTX) for patients with refractory or progressive disease, as it has been shown to reduce the incidence of various complications of chronic kidney disease (CKD) and improve patient outcomes 1.
Medical Management
The initial approach to managing SHPT involves addressing the underlying cause, typically chronic kidney disease or vitamin D deficiency. Key steps include:
- Restricting dietary phosphate intake to 800-1000 mg/day
- Prescribing phosphate binders such as calcium acetate (667 mg with meals) or sevelamer (800-1600 mg with meals)
- Correcting vitamin D deficiency by administering calcitriol, starting at 0.25 μg daily or alfacalcidol 0.25-0.5 μg daily, titrating up to maintain serum calcium within the normal range
- Adding a calcimimetic like cinacalcet, starting at 30 mg daily and titrating up to a maximum of 180 mg daily based on PTH levels, for patients with persistently elevated PTH despite these measures
Surgical Intervention
For patients with refractory or progressive SHPT, surgical intervention with TPTX is recommended, as it has been shown to quickly relieve electrolyte disorders and reduce the incidence of various complications of CKD, such as stroke and cardiovascular and all-cause mortality 1.
Monitoring and Adjustment
Regular monitoring of serum calcium, phosphate, and PTH levels, typically every 1-3 months, is crucial to adjust treatment as needed. If medical management fails to control PTH levels or if severe bone disease develops, consideration for referral for parathyroidectomy is necessary.
This approach targets the pathophysiology of secondary hyperparathyroidism by reducing phosphate load, normalizing vitamin D status, and directly modulating PTH secretion, effectively lowering PTH levels and reducing the risk of associated complications like renal osteodystrophy, as supported by recent clinical practice guidelines 2.
From the FDA Drug Label
The recommended starting oral dose of cinacalcet tablets is 30 mg once daily. Serum calcium and serum phosphorus should be measured within 1 week and intact parathyroid hormone (iPTH) should be measured 1 to 4 weeks after initiation or dose adjustment of cinacalcet tablets [see Dosage and Administration (2. 3)]. Cinacalcet tablets should be titrated no more frequently than every 2 to 4 weeks through sequential doses of 30, 60, 90, 120, and 180 mg once daily to target iPTH levels of 150 to 300 pg/mL. Cinacalcet tablets can be used alone or in combination with vitamin D sterols and/or phosphate binders During dose titration, serum calcium levels should be monitored frequently and if levels decrease below the normal range, appropriate steps should be taken to increase serum calcium levels, such as by providing supplemental calcium, initiating or increasing the dose of calcium-based phosphate binder, initiating or increasing the dose of vitamin D sterols, or temporarily withholding treatment with cinacalcet tablets
The management of secondary hyperparathyroidism in patients with chronic kidney disease on dialysis involves:
- Initiating cinacalcet at a dose of 30 mg once daily
- Titration of cinacalcet every 2 to 4 weeks to target iPTH levels of 150 to 300 pg/mL
- Monitoring serum calcium and serum phosphorus levels within 1 week and intact parathyroid hormone (iPTH) levels 1 to 4 weeks after initiation or dose adjustment
- Using cinacalcet alone or in combination with vitamin D sterols and/or phosphate binders
- Monitoring serum calcium levels frequently during dose titration and taking steps to increase serum calcium levels if they decrease below the normal range 3
From the Research
Management of Secondary Hyperparathyroidism
The management of secondary hyperparathyroidism involves various treatment approaches, including:
- The use of active vitamin D or vitamin D analogs to suppress parathyroid hormone (PTH) secretion 4, 5, 6
- Phosphorus binders to control serum phosphate levels 5, 7
- Calcium supplementation to control serum calcium concentrations 6
- Calcimimetics to stimulate calcium-sensing receptor of parathyroid cells and suppress PTH secretion 5, 7
- Percutaneous direct injection therapy of vitamin D, vitamin D analogue, or calcimimetics into parathyroid gland 5
Treatment Options
Different treatment options are available, including:
- Paricalcitol, a vitamin D analogue that has been shown to be effective in reducing PTH concentrations without causing significant hypercalcemia or hyperphosphatemia 4, 8
- Calcitriol, a vitamin D analogue that is commonly used to treat secondary hyperparathyroidism 4, 6, 8
- Cinacalcet, a calcimimetic that has been shown to be effective in reducing PTH levels and achieving recommended targets 7
- Sevelamer hydrochloride, a non-calcium containing phosphorus binder that can help prevent hypercalcemia 5
Treatment Outcomes
Studies have shown that treatment of secondary hyperparathyroidism can lead to: