The following drug information is obtained from various newswires, published
medical journal articles, and medical conference presentations.
Hyperparathyroidism / Hypercalcemia
Sensipar is an oral calcimimetic medication that lowers the
levels of parathyroid hormone, phosphurous and calcium in patients
undergoing kidney dialysis or in patients with parathroid
Sensipar is indicated for the treatment of secondary
hyperparathyroidism in chronic kidney disease patients on dialysis
and the treatment of elevated calcium levels (hypercalcemia) in
patients with parathyroid carcinoma.
The recommended starting oral dose of Sensipar is 30 mg once
FDA approval of Sensipar was based on three multicenter,
randomized, double-blind, placebo-controlled studies enrolling a
total of 1,136 chronic kidney disease (CKD) subjects on dialysis.
Among the subjects, 96% were on hemodialysis and 4% were on
peritoneal dialysis. Upon enrollment, 66% of the subjects were
receiving vitamin D sterols and 93% were receiving phosphate
binders. The average duration of dialysis prior to study enrollment
was 67 months. Treatment was administered at a dose of 30 mg once
daily and titrated every 3 or 4 weeks to a maximum dose of 180 mg
once daily to achieve an intact PTH (iPTH) of = 250 pg/mL. Results
showed that 40% of subjects taking Sensipar achieved an iPTH = 250
pg/mL compared with 5% on placebo. Data showed that Sensipar
reduced PTH while lowering Ca x P, calcium and phosphorus levels.
Secondary efficacy parameters also improved in patients treated
An open-label study in 10 subjects with parathyroid carcinoma
consisted of a dose-titration phase and a maintenance phase. The
doses ranged from 70 mg twice daily to 90 mg four times daily for
patients in the maintenance phase. The range of exposure was 2 to
16 weeks in the titration phase and 16 to 48 weeks for the
maintenance phase. Baseline mean (SD) serum calcium was 14.7 mg/dL.
The range of change from baseline to last measurement was –7.5 to
2.7 mg/dL during the titration phase and –7.4 to 0.9 mg/dL during
the maintenance phase (Figure 3). No patients maintained a serum
calcium level within the normal range.
Adverse events associated with the use of Sensipar may include
(but are not limited to) the following:
Mechanism of Action
Cinacalcet is an oral calcimimetic agent that increases the
sensitivity of the calcium-sensing receptor to activation by
extracellular calcium. The calcium-sensing receptors on the surface
of parathyroid gland cells also regulate parathyroid hormone (PTH)
secretion. Increased PTH stimulates osteoclastic activity resulting
in cortical bone resorption and marrow fibrosis. Increasing the
sensitivity of these receptors results in a lowering of PTH which
subsequently lowers serum calcium levels. In addition, significant
reductions in calcium may lower the threshold for seizures.
Franceschini N, Joy MS, Kshirsagar A.
Cinacalcet HCl: a calcimimetic agent for the management of primary
and secondary hyperparathyroidism. Expert Opin Investig
Drugs. 2003 Aug;12(8):1413-21.
National Kidney Foundation: K/DOQI clinical
practice guidelines: bone metabolism and disease in chronic kidney
disease. LAmerican Journal of Kidney Disease 4 2:S1-S201,