Single Dosing of Zoledronic Acid in Cancer Therapy Induced Bone Loss (CTIBL)

Inclusion Criteria:

* Postmenopausal women with Stage I, II or IIIa breast cancer being treated with a non-steroidal Aromatase Inhibitor (AI) .Negative bone scan (no bone metastases).
* Calculated creatinine clearance \> 40 ml/min
* Documented T score of less than or equal to -1.5 on Dual Energy X-ray Absorptiionmetry (DXA) scan at the lumbar spine or femoral neck within 3 months prior to screening.
* Urine NTx \> 50 nano moles(nM)based on second morning void.
* Signed informed consent.
* Ambulatory patients at least 18 years of age.
* Eastern Cooperative Oncology Group (ECOG)0-2.
* Ability to comply with trial requirements.

Exclusion Criteria:

* Bone Metastases.
* Any woman of child bearing potential.
* Patients with fractures occurring within three months prior to randomization. - Greater than a 2+ protein on urine dipstick without evidence of contamination or bacteriuria (may be repeated one time, at least a day apart).
* Calculated creatinine clearance less than 30 mL/min at screening.
* Serum calcium \> 2.75 mmol/L (11.0 mg/dL) or \< 2.00 mmol/L (8.0 mg/dL).
* Liver Function tests (LFT)\> 2.0 x upper limit of normal (ULN).
* Serum alkaline phosphatase \> 1.5 x ULN. History of hypersensitivity to bisphosphonates.
* Evidence of vitamin D deficiency (serum 25-(OH) D of less than 15 ng/ml).
* History of uveitis or iritis, except when secondary to trauma, and must have resolved \> 2 years prior to entry.
* A history of invasive malignancy of any organ system, treated or untreated, within the past 12 months prior to screening; excluding, basal cell or squamous cell carcinoma of the skin, colonic polyps with non-invasive malignancy which have been removed, Ductal Carcinoma in-situ (DCIS) that has been surgically removed, and Carcinoma in-situ (CIS) of the uterine cervix that has been surgically removed.
* Previous major solid organ transplant recipient or on a transplant waiting list.
* Treatment with any investigational drug within 30 days prior to randomization.
* History of hyperparathyroidism, hypoparathyroidism, Osteogenesis imperfecta, Paget's disease or any metabolic bone disease other than osteoporosis.
* Any medical condition which would interfere with the action of the study drug or limit life expectancy to less than 6 months.
* Any medical or psychiatric condition which, in the opinion of the investigator, would preclude the participant from adhering to the protocol or completing the trial.
* Prior treatment with IV bisphosphonates within the last 2 years.
* Previous use of oral bisphosphonates within the past 2 years (unless used for less than 8 weeks\*). \*NOTE: If used less than 8 weeks, the washout period is 6 months.
* Treatment with raloxifene, calcitonin, tibolone or hormone replacement therapy. The washout period for these medications is 6 months prior to randomization.
* Any treatment with strontium ranelate, samarium, sodium fluoride or parathyroid hormone.
* Use of systemic high dose corticosteroids at an average dose of \> 7.5 mg per day of oral prednisone or equivalent for a period of three months or more prior to screening.
* Known hypersensitivity to zoledronic acid or other bisphosphonates.
* Current active dental problems including infection of the teeth or jawbone (maxilla or mandibular); dental or fixture trauma, or a current or prior diagnosis of osteonecrosis of the jaw (ONJ), of exposed bone in the mouth, or of slow healing after dental procedures.
* Recent (within 6 weeks) or planned dental or jaw surgery (e.g.. extraction, implants).