Regpara Cinacalcet Hydrochloride Tablets

1. Indications and Usage
Secondary Hyperparathyroidism: Treatment of secondary hyperparathyroidism in patients with chronic kidney disease (CKD) on dialysis.
Hypercalcemia: Treatment of hypercalcemia in patients with parathyroid carcinoma.
2. Dosage and Administration
CKD on Dialysis: The recommended starting dose is 30 mg once daily. It should be taken with food or shortly after a meal. The dose can be titrated every 2 to 4 weeks based on serum calcium and parathyroid hormone (PTH) levels.
Parathyroid Carcinoma: The recommended starting dose is 30 mg twice daily. The dose can be titrated every 2 to 4 weeks based on serum calcium levels.
Administration: The tablet should be swallowed whole and not crushed or chewed.
3. Mechanism of Action
Calcium-Sensing Receptor Agonism: Cinacalcet increases the sensitivity of the calcium-sensing receptor on the surface of parathyroid cells.
Hormonal Suppression: This activation leads to a decrease in the synthesis and secretion of parathyroid hormone (PTH) and a subsequent reduction in serum calcium levels.
4. Safety and Warnings
Hypocalcemia: The most common serious adverse reaction is hypocalcemia, which can lead to QT interval prolongation, muscle spasms, paresthesia, and seizures.
Seizures: Seizures have been reported, particularly in patients with a history of seizures or in the setting of severe hypocalcemia.
Gastrointestinal Perforation: There have been post-marketing reports of gastrointestinal perforation, primarily in patients with a history of peptic ulcer disease or GI bleeding.
Hepatic Impairment: Cinacalcet is metabolized by the liver; dosage adjustments or close monitoring may be necessary in patients with moderate to severe hepatic impairment.
5. Adverse Reactions and Clinical Research
Common: Nausea, vomiting, diarrhea, and musculoskeletal pain are the most frequently reported adverse reactions.
Clinical Research: Pivotal trials have demonstrated that cinacalcet effectively lowers PTH levels in dialysis patients and serum calcium levels in parathyroid carcinoma patients compared to placebo.
6. Drug Interactions
CYP2D6 Substrates: Cinacalcet is a moderate inhibitor of CYP2D6 and can increase plasma concentrations of drugs metabolized by this enzyme (e.g., desipramine, metoprolol).
Digoxin: Cinacalcet may increase digoxin levels; monitoring is recommended.
Thiazide Diuretics: These may increase the risk of hypercalcemia, potentially counteracting cinacalcet’s effects.
Calcium and Vitamin D: Concomitant use requires careful monitoring of serum calcium levels to avoid hypocalcemia.
7. Pharmaceutical Information
Active Ingredient: Cinacalcet Hydrochloride.
Excipients: Lactose monohydrate, microcrystalline cellulose, croscarmellose sodium, magnesium stearate, and film-coating agents.
Appearance: Film-coated tablets (typically green or yellow-green).
Storage: Store at controlled room temperature, protected from light and moisture.