A Randomized Phase 3 Study to Evaluate Two Formulations of Romosozumab in Postmenopausal Women With Osteoporosis

A Multicenter, Randomized, Multiple-dose Phase 3 Study to Evaluate the Noninferiority of Romosozumab at a 90 mg/mL Concentration Compared With a 70 mg/mL Concentration in Postmenopausal Women With Osteoporosis

The purpose of this study is to compare 2 formulations of romosozumab (AMG 785) on bone mineral density (BMD) in postmenopausal women with osteoporosis.

Upon confirmation of eligibility, participants were randomized in a 22:5:22:5 ratio to the following treatment groups:

• Romosozumab 90 mg/mL
• Placebo 90 mg/mL
• Romosozumab 70 mg/mL
• Placebo 70 mg/mL

After completing a 6-month treatment period, participants entered a 3-month follow-up period with an end of study (EOS) at month 9.

For the analysis of efficacy endpoints, the 2 placebo groups were combined into a single placebo group. For safety analyses, the data for placebo were presented separately for each group.

Inclusion Criteria:

Postmenopausal women with osteoporosis at high risk for fracture defined as

• BMD T-score ≤ -2.50 at the lumbar spine, total hip, or femoral neck AND
• a history of fragility fracture or at least 2 other risk factors

Exclusion Criteria:

• BMD T score < -3.50 at the total hip or femoral neck.
• History of hip fracture.
• History of metabolic or bone disease (except osteoporosis).
• Use of agents affecting bone metabolism.
• Vitamin D insufficiency.
• History of solid organ or bone marrow transplants.
• Hyper- or hypocalcemia.
• Hyper- or hypothyroidism.
• Hyper- or hypoparathyroidism.