Eldecalcitol and Calcitriol in Postmenopausal Women With Low Bone Mineral Density or Mild Osteoporosis

Comparison of the Efficacy and Safety With Eldecalcitol and Calcitriol in Postmenopausal Women With Low Bone Mineral Density or Mild Osteoporosis

To investigate the efficacy and safety of eldecalcitol in postmenopausal women with low bone mineral density (BMD) or mild osteoporosis through a randomized, open-label, parallel controlled trial with calcitriol as the control.

Postmenopausal women with low bone mineral density (BMD) or mild osteoporosis will be randomized in a 1:1 ratio to receive open-label oral 0.75μg eldecalcit daily or open-label oral 0.5μg calcitriol daily for 12 months.

Inclusion Criteria:

1. Postmenopausal women (based on medical history) aged 50 or older and menopause time more than 2 years. If there is uncertainty regarding menopausal status, women 60 years of age and older will be considered postmenopausal.
2. BMD (determined by DXA) of lumbar L1-4 or total hip or femoral neck met one of the following conditions at screening:

1) low BMD: -2.5<T< -1.0, without vertebral and fragility fracture history 2) mild osteoporosis: T≤-2.5, without vertebral and fragility fracture history 3. Ambulatory outpatients 4. Written informed consent

Exclusion Criteria:

1. Severe vitamin D deficiency at screening (defined as serum 25OHD<10 ng/ml);Vitamin D repletion will be permitted and dosage will be at the discretion of investigators and subjects may be re-screened
2. Primary hyperparathyroidism, Cushing's syndrome, hyperthyroidism, gonadal insufficiency, osteogenesis impotence, rheumatoid arthritis, poorly controlled diabetes mellitus (HbA1c>9%), or other conditions that can cause secondary osteoporosis, or treatment with glucocorticoids in the 2 months prior to study entry
3. Had injected bisphosphonate once or more within 3 years before entering the study; or had received oral bisphosphonate oral for 6 months or more in the 3 years prior to study entry; or had received parathyroid hormone once or more in the 3 years before entering the study; or received 2 weeks or more of calcitonin or vitamin K or active vitamin D or selective estrogen receptor modulator or hormone replacement therapy or traditional Chinese medicine for bone pine within 2 months prior to study entry; or received subcutaneous anti-RANKL antibody at any time prior to study entry
4. Urolithiasis at screening
5. Hypercalcemia (serum calcium >10.4 mg/dL), or hypercalciuria (urine calcium>400 mg/gCr), or hyperuricemia (above 420 μmol/L in men and 360 μmol/L in women)
6. Severe liver disease such as cirrhosis or serious heart disease such as severe heart failure
7. Active malignant tumors or a history of malignant tumors within 5 years before informed consent obtained
8. History of allergy to vitamin D
9. Any condition which in the opinion of the investigator unfit for the study