PTH and hyperparathyroidism: In the multicenter Bone Biopsy Study for Dialysis Patients with the Secondary Hyperparathyroidism of End Stage Renal Disease (BONAFIDE) study, long-term treatment with cinacalcet substantially reduced PTH, diminished the elevated bone formation rate, lowered several biochemical markers of high-turnover bone disease toward normal, and generally improved bone histology [101].