Porontazin

Porontazin Uses, Dosage, Side Effects, Food Interaction and all others data.

Porontazin 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.

Secondary hyperparathyroidism is characterized by an elevation in parathyroid hormone (PTH) associated with inadequate levels of active vitamin D hormone. The source of vitamin D in the body is from synthesis in the skin and from dietary intake. Vitamin D requires two sequential hydroxylations in the liver and the kidney to bind to and to activate the vitamin D receptor (VDR). The endogenous VDR activator, calcitriol [1,25(OH)2 D3], is a hormone that binds to VDRs that are present in the parathyroid gland, intestine, kidney, and bone to maintain parathyroid function and calcium and phosphorus homeostasis, and to VDRs found in many other tissues, including prostate, endothelium and immune cells. VDR activation is essential for the proper formation and maintenance of normal bone. In the diseased kidney, the activation of vitamin D is diminished, resulting in a rise of PTH, subsequently leading to secondary hyperparathyroidism and disturbances in the calcium and phosphorus homeostasis.1 Decreased levels of 1,25(OH)2 D3 have been observed in early stages of chronic kidney disease. The decreased levels of 1,25(OH)2 D3 and resultant elevated PTH levels, both of which often precede abnormalities in serum calcium and phosphorus, affect bone turnover rate and may result in renal osteodystrophy. An in vitro study indicates that paricalcitol is not an inhibitor of CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1 or CYP3A at concentrations up to 50 nM (21 ng/mL).

Porontazin
Uses
Dosage
Side Effect
Precautions
Interactions
Uses during Pregnancy
Uses during Breastfeeding
Accute Overdose
Food Interaction
Half Life
Volume of Distribution
Clearance
Interaction With other Medicine
Contradiction
Storage

Trade Name	Porontazin
Availability	Prescription only
Generic	Paricalcitol
Paricalcitol Other Names	Paricalcitol
Related Drugs	cinacalcet, Sensipar, Zemplar, Hectorol, doxercalciferol
Type
Formula	C₂₇H₄₄O₃
Weight	Average: 416.6365 Monoisotopic: 416.329045274
Protein binding	99.8% (bound to plasma proteins)
Groups	Approved, Investigational
Therapeutic Class	Vitamin in bone formation, Vitamin-B preparations
Manufacturer
Available Country	Netherlands
Last Updated:	September 19, 2023 at 7:00 am

Uses

Chronic Kidney Disease Stages 3 And 4: Porontazin capsules are used for 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: Porontazin capsules are used for 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).

Porontazin is also used to associated treatment for these conditions: Secondary Hyperparathyroidism (SHPT)

How Porontazin works

Dosage

Porontazin dosage

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

Side Effects

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

Precaution

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

Interaction

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).

Food Interaction

Avoid antacids. Avoid taking aluminum-containing antacids chronically with paricalcitol as there is an increased risk of aluminum toxicity.
Exercise caution with grapefruit products. Grapefruit inhibits CYP3A4, and paricalcitol metabolism is mediated partially through CYP3A4; therefore, grapefruit may increase paricalcitol serum levels.
Take with or without food.