Wyeth Pharmaceuticals has reported the findings from a placebo-controlled phase 3 study of bazedoxifene 20mg extended to five years, which indicated a significant reduction versus placebo in new vertebral fractures in postmenopausal women with osteoporosis.
The data were presented at the American Society for Bone and Mineral Research (ASBMR) Annual Meeting in Denver, Colo.
Reportedly, the results being presented are from a two-year extension of a three-year phase 3 trial, which enrolled 7,492 generally healthy postmenopausal women aged 55 to 85 years with osteoporosis.
The primary endpoint of the three-year phase 3 study was the incidence of new vertebral fractures. Eligible subjects were randomised to daily treatment with bazedoxifene 20mg or 40mg, raloxifene (RLX) 60mg, or placebo. At the conclusion of the pivotal three-year study, a total of 4,216 subjects were enrolled in the extension to five years.
Patients receiving bazedoxifene 20mg continued on that dosage, while the RLX 60mg treatment arm was discontinued after the three-year database was finalised, and subjects receiving bazedoxifene 40mg were transitioned to bazedoxifene 20 mg after all subjects completed four years of treatment.
Additionally, at five years, the study showed that the incidence of new vertebral fractures was significantly reduced in the bazedoxifene 20mg group (4.5%) and in the group transitioned from bazedoxifene 40mg to 20mg (3.9%) compared with placebo (6.8%).
Stuart Silverman, the lead investigator of the study, said: “These new data are important in that they suggest the reduction in vertebral fracture risk with bazedoxifene seen at five years is comparable to that seen at three years.”