Pharmacokinetic and Bioequivalence Study of Eldecalcitol Soft Capsule 0.75 ug in Healthy Chinese Subjects Under Fasting and Fed Conditions: A Randomized, Single-center, Single-dose, Open-label, Two-period Crossover Study

Eldecalcitol is a novel active vitamin D3,1,25(OH)2D3 derivative for the treatment of osteoporosis, which was first approved in Japanin 2011. With a hydroxy propoxy substituent at the 2βposition of 1,25(OH)2D3, eldecalcitol not only kept the high safety advantage but also showed much stronger effects on bone, such as improving bone metabolism, increasing bone mineral density(BMD) and preventing new vertebral fracture.Here in this study, we have compared the pharmacokinetic and bioequivalent profiles of two eldecalcitol soft capsule formulations at a single dose of 0.75 μg both under fasting and fed condition in healthy Chinese volunteers.

28 subjects participated in the fasting trial were randomly assigned to two groups to receive a single-dose of 0.75 μg reference eldecalcitol soft capsule (R, produced by Chugai Pharmaceutical Co., Ltd. Japan) or test capsule (T, produced by Wenzhou Haihe Pharmaceutical Co., Ltd. China) with about 240 ml warm water in the first treatment period and to receive another formulation in the second treatment period. There was a 21-day wash-out between the two treatment periods. For those participated in the fed trial, it was almost the same, except that 30 subjects had unified breakfast with high fat and high calories 30 minutes before dosing.Blood samples (8ml) for the determination of eldecalcitol were collected pre-dose and at 0.5,1,2,2.5,3,3.5,4,4.5,5,6,8,10,12,15,24,36,48,72,96,120,144, and 168 h post-dose in the fasting trial. And for those participated in the fed trial, blood samples (8ml) were collected pre-dose and at1,2,3,4,5,6,8,10,12, 14,16,24,28,36,48,72,96,120,144,168, and 192 h post-dose.