Wyeth Presents Data from Five-Year Vertebral Fracture Prevention Study with Bazedoxifene

Collegeville, Pa. – Wyeth Pharmaceuticals, a division of Wyeth (NYSE: WYE), announces findings from a placebo-controlled Phase 3 study of bazedoxifene 20 mg extended to five years, which indicated a significant reduction versus placebo in new vertebral fractures in postmenopausal women with osteoporosis. These and other data were presented at the American Society for Bone and Mineral Research (ASBMR) Annual Meeting in Denver, Colo. Bazedoxifene, a selective estrogen receptor modulator (SERM), is under clinical investigation for the prevention and treatment of postmenopausal osteoporosis.

“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,” says Stuart Silverman, M.D., Clinical Professor of Medicine at the University of California, Los Angeles and Cedars-Sinai Medical Center, and the study’s lead investigator.

About Study 301

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 randomized to daily treatment with bazedoxifene 20 mg or 40 mg, raloxifene (RLX) 60 mg, 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 20 mg continued on that dosage, while the RLX 60 mg treatment arm was discontinued (as prespecified in the protocol) after the three-year database was finalized, and subjects receiving bazedoxifene 40 mg were transitioned to bazedoxifene 20 mg after all subjects completed four years of treatment. At five years, the study showed that the incidence of new vertebral fractures was significantly reduced in the bazedoxifene 20 mg group (4.5%) and in the group transitioned from bazedoxifene 40 mg to 20 mg (3.9%) compared with placebo (6.8%). This corresponds to relative risk reductions of 35% (P=0.014) and 40% (P=0.005), respectively. The incidence of venous thromboembolic events in this Phase 3 clinical trial was higher in bazedoxifene-treated subjects when compared with placebo. This finding is consistent with what was seen at three years.

Additional New Bazedoxifene Data Presented at ASBMR

Assessment of the Effect of Bazedoxifene on Non-Vertebral Fracture Risk (McCloskey EV, et al)

Data were also presented from a post-hoc analysis performed using the Fracture Risk Assessment Tool (FRAX®), which was developed by the World Health Organization to calculate a womans 10-year risk of experiencing an osteoporotic fracture. This post-hoc analysis indicated that the higher a womans risk of a fracture, the greater the reduction in non-vertebral fractures when receiving bazedoxifene therapy based on her FRAX score.

Safety and Tolerability of Bazedoxifene in Postmenopausal Women with Osteoporosis: Results of a 5-Year, Randomized, Placebo-controlled Phase 3 Trial (de Villiers TJ, et al)

Bazedoxifene five-year safety and tolerability data in postmenopausal women with osteoporosis were also presented. The incidence of adverse events (AEs), serious AEs and discontinuations due to AEs was similar to that seen in the placebo group. The incidence of cardiac or cerebrovascular events, including myocardial infarction and stroke, in the bazedoxifene treatment groups was similar to that seen in the placebo group. Subjects treated with bazedoxifene had a higher incidence of deep venous thrombosis, hot flushes and leg cramps compared with placebo-treated subjects. The effect of bazedoxifene on the breast and endometrium was comparable to placebo.

Cost-effectiveness of Bazedoxifene in the US Incorporating the FRAX ® Algorithm (Strom, et al)

Data from an analysis performed using a Marcov cohort model and published U.S. cost and epidemiological data evaluated the potential cost-effectiveness and intervention thresholds of bazedoxifene treatment (20 mg and 40 mg doses combined) compared to placebo. Cost-effective scenarios were projected for women with strong risk factors and with a T-score above the threshold for osteoporosis. When effect was modeled for non-vertebral fractures, the data suggested that potential cost effectiveness improved further in women from the age of 60 years with prior fracture and at the threshold of osteoporosis (T-score=-2.5 SD).