[Retrospective assessment of effective and safety of cinacalcet for the treatment of secondary hyperparathyroidism depending on basal iPTH level].

Objective: Cinacalcet is a calcimimetic agent, recommended for treating refractory secondary hyperparathyroidism in patients undergoing dialysis. The aim of this study was to evaluate the efficacy and safety of cinacalcet, comparing patients with baseline iPTH > 300 pg/ml with those with iPTH < 300 pg/ml.

Method: Observational retrospective study of patients being treated with cinacalcet 30 mg/day from January 2008 to January 2009. We studied 26 patients, 15 with iPTH > 300 pg/ml and 11 with iPTH < 300 pg/ml. The primary efficacy outcome was that there was a reduction between baseline and final iPTH (4 month). The secondary efficacy outcome were the reduction between basal and final calcium, phosphorus, Ca x P, and the percentage of patients with an iPTH decrease > 30%. The safety was evaluated based on the most frequent adverse effects and the levels of serum calcium < 8.6 mg/dl.

Results: Patients with initial iPTH > 300 had significant differences before and after cinacalcet treatment in iPTH (563.49+286.88 pg/ml vs 315.15+201.948 pg/ml; P=.017) and serum calcium (9.1+1.77 mg/dl vs 8.15+1.2mg/dl; P=.02). There were no significant differences in patients with initial iPTH < 300 pg/ml. A decrease greater than 30% from baseline iPTH was observed in 60% of patients with baseline iPTH > 300 pg/ml, and only in 27.3% of those with basal iPTH < 300 pg/ml (P=.098). Patients did not show gastric intolerance.

Conclusions: Cinacalcet is an effective and safe drug for controlling secondary hyperparathyroidism in dialysis, mainly when it is used in patients with baseline iPTH > 300 pg/ml.