Objective: To compare the efficacy and tolerability of once-weekly (OW) alendronate (ALN) 70 mg and raloxifene (RLX) 60 mg daily in the treatment of postmenopausal osteoporosis.
Design: This 12-month, randomized, double-blind study enrolled 456 postmenopausal women with osteoporosis (223 ALN, 233 RLX) at 52 sites in the United States. Efficacy measurements included lumbar spine (LS), total hip, and trochanter bone mineral density (BMD) at 6 and 12 months, biochemical markers of bone turnover, and percent of women who maintained or gained BMD in response to treatment. The primary endpoint was percent change from baseline in LS BMD at 12 months. Adverse experiences were recorded to assess treatment safety and tolerability.
Results: Over 12 months, OW ALN produced a significantly greater increase in LS BMD (4.4%, P < 0.001) than RLX (1.9%). The percentage of women with > or = 0% increase in LS BMD (ALN, 94%; RLX, 75%; P < 0.001) and > or =3% increase in LS BMD (ALN, 66%; RLX, 38%; P < 0.001) were significantly greater with ALN than RLX. Total hip and trochanter BMD increases were also significantly greater (P < or =0.001) with ALN. Greater (P < 0.001) reductions in N-telopeptide of type I collagen and bone-specific alkaline phosphatase were achieved with ALN compared with RLX at 6 and 12 months. No significant differences in the incidence of upper gastrointestinal or vasomotor adverse experiences were seen.
Conclusion: ALN 70 mg OW produced significantly greater increases in spine and hip BMD and greater reductions in markers of bone turnover than RLX over 12 months. A greater percentage of women maintained or gained BMD on ALN than RLX. Both medications had similar safety and tolerability profiles.