Abstract (EN):
Aims: To evaluate the relationship between the severity of secondary hyperparathyroidism (SHPT) - defined in terms of baseline plasma intact parathyroid hormone (iPTH) level -and the magnitude of response to cinacalcet. Materials and methods: In this post hoc analysis, data were pooled from three randomized, placebo-controlled trials in which dialysis patients with iPTH >= 300 pg/ml were dose-titrated with cinacalcet or placebo in addition to conventional treatment to achieve iPTH <= 250 pg/ml. In 953 patients analyzed (cinacalcet, 545; placebo, 408), baseline iPTH levels were categorized in 100 pg/ml intervals (300 - >= 1,000 pg/ml), and the impact of baseline iPTH on changes in iPTH, phosphate (P), calcium (Ca) and calcium-phosphate product (Ca x P) was evaluated. Results: Cinacalcet reduced iPTH (47% reduction), P (9%), Ca (7%), and Ca x P (15%) across all subgroups. For patients receiving cinacalcet, the mean percentage reduction from baseline in iPTH varied from 35 to 55%, being consistently decreased across the severity subgroups. The mean absolute change in iPTH was more pronounced in patients with higher baseline iPTH levels, particularly in the >= 1,000 pg/ml subgroup vs. the other subgroups. However, as baseline iPTH levels increased, iPTH <= 250 pg/ml was achieved in fewer patients. A trend towards greater absolute change from baseline was observed for P in patients with more severe disease (iPTH >= 800 pg/ml) treated with cinacalcet compared with patients with less severe disease (iPTH 300 - < 800 pg/ml). Conclusions: Cinacalcet lowers plasma iPTH and serum P, Ca and Ca x P levels in dialysis patients with SHPT, regardless of disease severity. Patients with more severe disease experienced greater reductions in PTH and P, but fewer achieved iPTH <= 250 pg/ml by the efficacy assessment phase. Use of cinacalcet when baseline PTH is lower may result in more stable control of SHPT and help to control bone and mineral alterations.
Idioma:
Inglês
Tipo (Avaliação Docente):
Científica
Nº de páginas:
11