• Whether the increase from baseline to 18 months in lumbar spine BMD induced by teriparatide statistically significantly exceeds that obtained with alendronate in women and men taking GC for a minimum of 3 months
  

• Whether the increase from baseline to 18 months in lumbar spine BMD induced by teriparatide statistically significantly exceeds that obtained with alendronate in women taking GC for a minimum of 3 months
  
• The time course of BMD response at the lumbar spine from baseline until 18 months in women and men combined, and in women separately
  
• To assess the effects on: the change from baseline in femoral neck and total hip BMD at 18 months,24 months,and 36 months,and in lumbar spine BMD at 24 and 36 months
  
• The time course of BMD response at the femoral neck and total hip from baseline until 18 months
  
• The time course of BMD response at the lumbar spine, femoral neck, and total hip from baseline until 36 months
  
• The time course of response of biochemical markers of bone turnover from baseline until 18 months in subjects from a subset of the study centers
  
• The time course of response of biochemical markers of bone turnover from baseline until 36 months in subjects
  
• Any fracture, nonvertebral fractures, vertebral fractures, clinical vertebral fractures, and severity fractures at 36 months
  
• Adverse experience, laboratory variables, and other aspects of subject safety and tolerance of the study drugs
  

Inclusion Criteria:

• Men or women age 21 years or older
• Taking on average 5.0 mg/day prednisone or equivalent

Exclusion Criteria:

• Taking bisphosphonates within past 6 months
• More than 30 micrograms/day of estradiol or equivalent in past 3 months
• History of alcoholism or drug abuse in past year
• Pregnant women or nursing mothers