Fosamax Actonel Comparison Trial

Comparison: - once-weekly alendronate 70 mg compared with - once-weekly risedronate 35 mg in women with postmenopausal osteoporosis Design: - randomized, double-blind trial conducted at 78 sites in the USA - postmenopausal women - 40 years of age or older - over 25 years of age if surgically menopausal - low bone density* - 1,042 patients * defined as a BMD of >= -2.0 SD below young adult mean BMD in at least one site (total hip, hip trochanter, femoral neck, or PA lumbar spine) Exclusion criteria: - history of esophageal abnormalities - those unable to remain upright for at least 30 minutes after dosing - low concentrations of vitamin D - metabolic bone disease - use of systemic estrogen, estrogen analogues, tibolone, or anabolic steroids within the past 6 months - use of bisphosphonates or parathyroid hormone within the past 12 months - daily prednisone 7.5 mg > 1 month in the last 6 months - use of immunosupressants Patients were treated for 12 months* - both the patient & investigators were blinded * an additional 12 months where only the patients were blinded (not yet been reported) Outcomes: - BMD at the hip trochanter dual energy X-ray absorptiometry (DEXA) at 0 6, & 12 months - other BMD assessments included posterior-anterior (PA) lumbar spine proximal femur - urinary N-telopeptide of type I human collagen - serum bone-specific alkaline phosphatase - serum N terminal propeptide of type 1 procollagen Results: 1) alendronate increased bone density of the hip by 3.4% in one year compared with 2.1% for risedronate 2) differences also favored alendronate at lumbar spine 3) reduction in bone turnover (all biochemical markers) greater with alendronate than risedronate at 3-12 months 4) adverse effects was similar in the 2 groups - upper GI effects in 20-22%

References

Prescriber's Letter 11(12): 2004 Once-Weekly Alendronate Compared with Once-Weekly Risedronate Detail-Document#: 201203 (subscription needed) http://www.prescribersletter.com