The purpose of the study was clarify the effect of the
cathepsin K inhibitor
ONO-5334 on bone resortion markers using sustained release (SR) formulations with different pharmacokinetic (PK) patterns, and identify the optimal SR formulation. The PK profiles and pharmacodynamic effect on
bone resorption markers of 4 SR candidates formulations were evaluated in healthy postmenopausal women within a randomized, 2-part, open-label crossover study. In Part A, subject received a single dose of each formulation orally in the fed state. In Part B, two selected formulations were evaluated in the fasted state. From the results from Part A, C(max) was reduced and plasma concentrations of
ONO-5334 were sustained with all SR formulations compared with an immediate release
tablet. In pharmacodynamics, the level of
C-terminal telopeptide of type I collagen (CTX) in serum and urine were inhibited with SR
tablets rather than with granules. C max and area under the concentration-time curve from time 0 to the last measurable time point (AUC(0-t)) of SR
tablets were higher than those of granules. From Part B, C max in the fasted condition was lower than that in the fed condition with two SR
tablets. In contrast, C(24 h) in the fasted condition was slightly higher than that in the fed condition, but AUC(0-t) was similar. The inhibitory effect on CTX in serum and urine may depend on the PK pattern of
ONO-5334. The SR
tablets was well tolerated in postmenopausal women and has the optimal SR profiles on pharmacodynamics effect on bone resortion markers and PK profile. These results suggest that SR
tablets of
ONO-5334 are an excellent
drug candidate for
osteoporosis.