Study of Transitioning From Alendronate to Denosumab

A Randomized Study to Evaluate Safety and Efficacy of Transitioning Therapy From Alendronate to Denosumab (AMG 162) in Postmenopausal Women With Low Bone Mineral Density

The study will evaluate the efficacy and safety of transitioning postmenopausal women on current alendronate therapy to denosumab. Endpoints studied will include bone mineral density, bone turnover markers and bone histology in a subset of subjects.

Inclusion Criteria:

• Postmenopausal females 55 yrs or older
• Received alendronate therapy for osteoporosis for at least 6 months prior to entry into study
• Lumbar spine or total hip Bone Mineral Density (BMD) corresponding to T-score ≤ -2 and ≥ -4

Exclusion Criteria:

• Vitamin D deficiency
• Administration of intravenous bisphosphonate, or
• fluoride (except for dental treatment) or
• strontium ranelate
• Administration of Parathyroid Hormone (PTH) or Parathyroid Hormone (PTH) derivatives (eg; teriparatide) within the last year
• Administration of any bisphosphonate other than alendronate (ALN) within 1 year of screening