Ent-Cinacalcet Hydrochloride is primarily used in the treatment of secondary hyperparathyroidism in patients with chronic kidney disease who are on dialysis. It helps to regulate calcium and phosphorus levels in the blood by modulating the activity of the parathyroid glands, thereby reducing the risk of bone disorders and cardiovascular complications associated with abnormal mineral metabolism. Additionally, it is employed in the management of hypercalcemia in patients with parathyroid carcinoma, where it aids in lowering elevated calcium levels by inhibiting excessive parathyroid hormone secretion. Its application is crucial in improving patient outcomes by maintaining mineral balance and reducing the progression of related diseases.