Clinical Efficacy and Safety Comparative Study Between CMAB807 Injection and Prolia® .

Inclusion Criteria:

1. Fully informed, understood, voluntary participate, and the patient himself orguardian agree to sign the written informed consent and patient be able to complywith the protocol;

2. Aged from 50 years to 85 years, inclusive;

3. Spontaneous amenorrhea time ≥ 2 years, or bilateral oophorectomy≥ 2 years. If thestatus of bilateral ovariectomies is unknown, the menopause status should beconfirmed by follicle stimulating hormone(FSH) level≥ 40IU/L;

4. Based on the results of dual energy X-ray absorptiometry, BMD of lumbarspine(L1~L4), femoral neck or total hip: -4.0<T-Score≤-2.5；

5. There must be at least one of the following risk factors:

• History of osteoporotic fracture;

• Father's and mother's hip fracture history, or both parents';

• Low body mass index(≤19kg/m^2);

• Patient's age was equal or greater than 70 years old;

• Current smoker;

• CTX1 was one standard deviation higher than that of healthy premenopausal womenwithin screening period(ie, CTX1>0.43ng/mL);

6. Ability to act independently.

Exclusion Criteria:

1. Suffering from the following diseases known to affect calcium or bone metabolism:

• Various metabolic bone diseases, such as osteogenesis imperfecta andosteomalacia;

• Paget's osteopathy;

• Cushing's syndrome;

• Hyperprolactinemia;

• Hypopituitarism;

• Acromegaly;

• History of hyperparathyroidism or hypoparathyroidism;

• History of hyperthyroidism or hypothyroidism(hypothyroidism patients can beincluded: only receiving stable thyroid hormone replacement therapy, if thethyroid stimulating hormone(TSH) level is normal, or 5.5μIU/mL<TSH≤10.0μIU/mL,and free thyroxine(FT4) is in normal range can be included);

• Malabsorption syndrome or various gastrointestinal diseases associated withmalabsorption, such as Crohn's disease and chronic pancreatitis;

• Abnormal level of blood calcium: the current diagnosis of hypocalcemia orhypercalcemia or albumin corrected serum calcium levels are not within thelaboratory normal range(calcium supplements should not be used for at least 8hours prior to serum calcium testing);

• Vitamin D deficiency: 25 hydroxyvitamin D concentration<20ng/mL. Allowed toretest after oral vitamin D2 soft capsules in the screening period. If theconcentration of 25 hydroxyvitamin D is more than or equal to 20ng/mL， it canbe selected;

• Other diseases such as rheumatoid arthritis, gout, multiple myeloma, etc;

2. Medical history of two or more vertebrae fractures;

3. Malignant tumor(excluding skin basal cell carcinoma or squamous cell carcinoma,cervical carcinoma in situ or breast ductal carcinoma in situ) in recent 5 years;

4. Severe renal function damage(creatinine clearance rate<30mL/min), or dialysis,urinary calculi or chronic cystitis;

5. Suffering from the following liver or biliary diseases:

• Liver cirrhosis;

• Biliary abnormalities(except for Gilbert syndrome or asymptomatic gallstones);

• Positive hepatitis C virus antibody(HCV-Ab) and the titer of HCV-RNA exceededthe upper limit of norma;

• Positive hepatitis B suface antigen(HBsAg) and peripheral blood HBV-DNA titer ≥1000 capies[CPS]/mL or 200IU/mL;

• Unstable liver disease: defined as liver ascites, hepatic encephalopathy,coagulopathy, hypoalbuminemia, varicosis in esophagus or stomach fundus orpersistent hepatic jaundice;

6. Liver transaminase: aspartate aminotransferase≥2.0×upper limit of norma value(ULN),alanine aminotransferase≥2.0ULN, alkaline phosphatase≥1.5ULN or totalbilirubin≥1.5ULN;

7. Suffering from the following oral diseases:

• Osteomyelitis or osteonecrosis of the jaw, previously or currently;

• Actue dental or mandibular disease requiring stomatological surgery;

• Planned invasive dental surgery during the trial period;

• Dental or stomatological surgery have not healed;

8. Conditions which can influence bone mineral density determination by dual energyX-ray absorptiometry:

• Less than two lumbar vertebrae can be measured;

• Height, weight or waistline may hinder accurate measurement;

• Other conditions that may affect bone density testing

9. Received anti-osteoporosis drugs or those drugs may affect bone metabolism:

• Use of injectable bisphosphonates, fluoride or strontium within 2 years beforescreening;

• Use of oral bisphosphonates: more than 2 years, or more than 3 months but lessthan 2 years and discontinued from last dosage less than 1 year,simultaneously;

• Usage of any drugs which may affect bone metabolism within 6 weeks beforescreening: parathyroid hormone or parathyroid hormone analogue(such asteriparatide); assimilative hormone or testosterone; glucocorticoid(equivalentto prednisone>5mg/day for more than 10 days); systemic hormone replacementtherapy; selective estrogen receptor regulator(such as reloxifene); tibolone;calcitonin; active vitamin D and ite analogues, other bone active drugs includeanticonvulsant drugs(except benzodiazepines) and he[arin; long-term systemicuse of ketoconazole, androgen, adrenocorticotropic hormone, cinacalcet,aluminum, lithium, protease inhibitors, methotrexate, gonadotropin releasinghormone agonist;

• Patients who have received RANKL inhibitors previously;

10. Positive HIV antibody;

11. Known alcoholism or drug abuse(during 12 months before screening), because alcoholor drug abuse may interfere with subject's understanding or finish of trial;

12. Known allergy to test drug, reference drug or basic drug and its excipients;

13. Participate in interventionary clinical study(drug or device) within one monthbefore screening;

14. Other serious, acute or chronic diseases, mental disorders or laboratoryabnormalities, which are judged by investigator to be unsuitable to participate thisstudy.