Conditions: Osteoporosis
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 246
Healthy volunteers: no

Brief summary:
The study will evaluate the both the efficacy of odanacatib on Bone Mineral Density (BMD) and the safety of odanacatib for postmenopausal osteoporosis in patients previously treated with alendronate. The primary hypothesis of the trial is that treatment with odanacatib 50 mg once weekly will increase bone mineral density at the femoral neck compared to placebo at the end of 24 months.

Detailed description:

Arms:
arm 1: Odanacatib 50 mg tablets once weekly for 24 months. Vitamin D3 (dietary supplement), two 2800 IU tablets, taken once weekly for 24 months. Participants received calcium carbonate supplements as needed to ensure a daily calcium intake of 1200 mg. arm 2: Placebo to odanacatib 50 mg tablets once weekly for 24 months. Vitamin D3 (dietary supplement), two 2800 IU tablets, taken once weekly for 24 months. Participants received calcium carbonate supplements as needed to ensure a daily calcium intake of 1200 mg.

Interventions: intervention 1: Odanacatib intervention 2: Placebo intervention 3: Vitamin D3 intervention 4: Calcium
Intervention descriptions: intervention 1: Odanacatib 50 mg tablets once weekly for 24 months intervention 2: Placebo to odanacatib 50 mg tablets once weekly for 24 months intervention 3: Vitamin D3, two 2800 IU tablets, taken once weekly for 24 months intervention 4: Participants will receive calcium carbonate supplements as needed to ensure a daily calcium intake of 1200 mg.

Protocol document: