Paricalcitol

Chronic Kidney Disease Stages 3 And 4: Paricalcitol capsules are indicated in adults and pediatric patients 10 years of age and older for the prevention and treatment of secondary hyperparathyroidism associated with Chronic Kidney Disease (CKD) Stages 3 and 4.

Chronic Kidney Disease Stage 5: Paricalcitol capsules are indicated in adults and pediatric patients 10 years of age and older for the prevention and treatment of secondary hyperparathyroidism associated with CKD Stage 5 in patients on hemodialysis (HD) or peritoneal dialysis (PD).

Paricalcitol is a synthetic, biologically active vitamin D analog of calcitriol with modifications to the side chain (D2) and the A (19-nor) ring. Preclinical andin vitro studies have demonstrated that paricalcitol's biological actions are mediated through binding of the VDR, which results in the selective activation of vitamin D responsive pathways. Vitamin D and paricalcitol have been shown to reduce parathyroid hormone levels by inhibiting PTH synthesis and secretion.

Usual Adult Dose for Secondary Hyperparathyroidism:

Initial dose:

Stage 3 or 4 Chronic Kidney Disease (CKD): Initial dosing is based on baseline intact parathyroid hormone (iPTH):

• 500 pg/mL or less: 1 mcg orally daily OR 2 mcg orally 3 times a week
• Over 500 pg/mL: 2 mcg orally daily OR 4 mcg orally 3 times a week

Stage 5 Chronic Kidney Disease (CKD):

• Starting dose (micrograms) = baseline iPTH level (pg/mL)/80
• Starting dose is given orally 3 times a week; only start if baseline serum calcium has been adjusted to 9.5 mg/dL or lower.

Usual Pediatric Dose for Secondary Hyperparathyroidism:

Safety and efficacy have not been established in pediatric patients. The following is dosing used in a very small pediatric trial. No data are available on children under 5 years old.

Initial dose, children 5 to 18 years: 0.04 mcg/kg three times per week if baseline intact parathyroid hormone (iPTH) is less than 500 pg/mL 0.08 mcg/kg three times per week if baseline iPTH is 500 pg/mL or higher. Injected as a bolus dose through a hemodialysis vascular access port at any time during dialysis

Maximum frequency: Every other day

Digitalis; ketoconazole & other strong P450 3A inhibitors including atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, voriconazole. May interfere absorption with cholestyramine (cap only). Increased risk of hypercalcemia with prescription-based phosphate or vit D-related medicinal products & Ca-containing prep or thiazide diuretics. Mg- & Al-containing prep (eg, antacids, phosphate-binders).

Hypersensitivity, Hypercalcemia, hypervitaminosis D.

Nausea, Vomiting, Edema, Palpitation, Chills, Pneumonia, Lightheadedness, GI bleeding, Flu, Sepsis, Hypokalemia, Hypercalcemia, Increase in blood creatinine.

This drug should not be used during pregnancy unless the benefit outweighs the risk to the fetus.

• AU TGA pregnancy category: C
• US FDA pregnancy category: C

Lactation: Not known if distributed into breast milk, use caution

Excessive administration of vitamin D compounds, including Paricalcitol Capsules, can cause over suppression of PTH, hypercalcemia, hypercalciuria, hyperphosphatemia, and adynamic bone disease.

Thyroid drugs & hormone.