Phase III, prospective, randomized, parallel, double blind, placebo-controlled study to determine whether Teriparatide can accelerate bone healing in unstable intertrochanteric fracture patients treated with Proximal Femoral Nail Antirotation (PFNA) assessed by radiographic and clinical outcomes.

Patients will undergo screening assessment to determine the eligibility for study participation and will be randomized in 1:1 ratio to receive Teriparatide 20 μg or placebo subcutaneous once daily for 12 weeks.

All patients will receive supplements of 1000 mg/day of elemental calcium and 20,000 IU/week of vitamin D2.

Patients will be scheduled to clinic visit for radiographic and clinical assessment at 2, 6,12 and 24 weeks postoperatively. Each participant will be in the study for 6 months in total.

Inclusion Criteria:

1. Male and female patient, age ≥ 50 years at the time of screening
2. Unstable intertrochanteric fracture (AO/OTA 31-A2 and 31-A3)
3. Treated by proximal femoral nail antirotation (PFNA)

Exclusion Criteria:

1. Known hypersentivity to teriparatide or any form of PTH or analogue
2. Metabolic bone disease other than primary osteoporosis (including Hyper Parathyroidism and Paget's disease of bone)
3. Increased baseline risk of osteosarcoma (Paget's disease of the bone, previous primary skeletal malignancy, or skeletal exposure to therapeutic irradiation)
4. History of malignant neoplasm in the 5 years prior to the study (with the exception of superficial basal cell carcinoma or squamous cell carcinoma) and carcinoma in situ of the uterine cervix treated less than 1 year prior to the study.
5. Pre-existing of hypercalcemia (total serum calcium >10.5 mg/dL or 2.6 mmol/L)
6. Abnormally elevated serum intact parathyroid hormone at screening (serum PTH > 70 pg/mL)
7. Severe vitamin D deficiency (25-hydroxyvitamin D < 12 ng/mL)
8. Unexplained elevations of alkaline phosphatase (ALP > 120 UL)
9. Severe renal impairment (CrCL < 30 mL/min)
10. Current treatment with digoxin and necessary to continue use during the study
11. Concurrent treatment with oral bisphosphonates, selective estrogen receptor modulator (SERMs), calcitonin, estrogen (oral, transdermal, or injection), progestin, estrogen analog, estrogen agonist, estrogen antagonist or tibolone, and active vitamin D3 analogs. (Previous treatment is allowed but must be discontinued at screening)
12. Previous treatment with strontium ranelate for any duration, intravenous bisphophonates within 12 months prior to the screening date, and/or denosumab within 6 months prior to the screening.
13. Previous treatment with teriparatide, PTH or other PTH analogs, or prior participation in any other clinical trial studying teriparatide, PTH or other PTH analogs

double blind, placebo-controlled