Cinacalcet, a calcimimetic used to treat secondary hyperparathyroidism (SHPT) in adults, also appears relatively safe and effective for children younger than 5 years receiving maintenance dialysis, according to results from a small study published in Clinical Nephrology.
Thirteen patients on peritoneal dialysis and 5 on hemodialysis (aged 8 months to 4.5 years) initiated cinacalcet at a starting dose of 6.2 mg daily (0.55 mg/kg/day) for SHPT not responsive to dietary adjustments, phosphate binders, and vitamin D therapy. Parathyroid hormone (PTH) levels fell significantly from 929 to 427 pg/mL during the first month of therapy, Shweta Shah, MD, and colleagues from Baylor College of Medicine in Houston, reported. Serum phosphorus decreased from 5.6 to 4.8 mg/dL at 1 month, with effects persisting for 6 months, possibly reflecting reductions in bone turnover or bone-specific alkaline phosphatase. Nine children receiving concomitant growth hormone grew taller: Median height Z-score at initiation –2.32 vs –1.83 at 6 months.
Asymptomatic hypocalcemia (serum calcium levels less than 9.4 mg/dL) developed in 3 patients despite calcium supplementation. The investigators recommended that serum calcium levels be measured within a week of cinacalcet initiation and frequently during dose titrations for hypocalcemia, with adjustments of vitamin D therapy, calcium and phosphate supplements, and phosphate binder doses as needed. No other adverse events were reported.
“Our study, along with others, highlights the importance of including cinacalcet in the treatment armamentarium of secondary hyperparathyroidism in children receiving chronic dialysis,” Dr Shah’s team wrote.
Joseph C, Shah S, Geer J, et al. Cinacalcet for secondary hyperparathyroidism in end-stage renal disease patients below age 5 years. Clin Nephrol. 92:279-286