ACTIVE COMPARATOR TRIAL OF TERIPARATIDE VERSUS ALENDRONATE IN THE TREATMENT OF GLUCOCORTICOID-INDUCED OSTEOPOROSIS

Background: Bisphosphosphonates are the current standard of care for glucocorticoid-induced osteoporosis. However, the role of anabolic bone agents is not well-established and no trials have compared bisphosphonates to anabolic treatment.Objectives: The primary objective was to determine whether the increase from baseline to 18 months in lumbar spine bone density with teriparatide exceeded that obtained with alendronate. Secondary outcomes included change in proximal femur bone mineral density, time course of bone density change, change in markers of bone turnover and fracture incidence.Methods: We conducted an 18 month randomized controlled trial in 428 women and men, 22 to 89 years of age who had taken glucocorticoids ≥3 months (prednisone equivalent ≥5 mg per day) and who had either low bone mineral density or antecedent fractures. Subjects received either teriparatide, 20 μg (n=214) or alendronate, 10 mg (n=214) once daily. The primary intent-to-treat analysis examined endpoint (the last observation during treatment).Results: Subjects (81% women) had a mean [SD] age of 57 [14] years (range 22 - 89). Median (25th, 75th interquartile range) glucocorticoid daily dose and use duration were 7.5 (5.0, 10.0) mg and 1.3 (0.3, 5.5) years. Baseline lumbar spine, total hip, and femoral neck bone mineral density = 0.85 [0.13] 0.75 [0.12], and 0.69 [0.12] g/cm (T-score = -2.5 [1.0], -2.0 [0.9], and -2.1 [0.8]), respectively. A total of 208 (49%) randomized subjects (100 alendronate; 108 teriparatide) had a prevalent fracture. Both treatments significantly increased bone density at the lumbar spine, total hip and femoral neck, with greater increases in the teriparatide group than alendronate at endpoint. Fewer new vertebral fractures occurred with teriparatide (1/171, 0.6%) than with alendronate (10/165, 6.1%) (P=0.004), using baseline and endpoint radiographs. The incidence of nonvertebral fractures was not significantly different between alendronate (8/214, 3.7%) and teriparatide (12/214, 5.6%). Percent changes from baseline in bone mineral density (g/cm) Time point N Alendronate Mean [SE] N Teriparatide Mean [SE] Lumbar spine Month 3 184 1.7 [0.5]* 183 2.5 [0.5]* Month 6 173 2.2 [0.5]* 178 4.3 [0.5]*‡ Month 12 159 3.5 [0.6]* 170 6.7 [0.5]*‡ Month 18 148 3.9 [0.6]* 156 8.2 [0.6]*‡ Endpoint 195 3.4 [0.7]* 198 7.2 [0.7]*‡ Total Hip Month 12 157 1.9 [0.5]* 167 3.1 [0.5]*† Month 18 144 2.4 [0.6]* 156 3.8 [0.6]*‡ Endpoint 176 2.2 [0.5]* 185 3.6 [0.5]*‡ Femoral Neck Month 12 157 2.1 [0.8]* 167 4.1 [0.8]*‡ Month 18 144 2.8 [0.8]* 156 4.4 [0.8]*† Endpoint 176 2.1 [0.7]* 185 3.7[0.8]*† *P<0.01 Within treatment; ‡P<0.01, †P<0.05 Between treatment. Conclusion: In this 18 month active comparator trial, teriparatide was more efficacious than alendronate in increasing bone density and in reducing incident vertebral fractures in subjects with glucocorticoid-induced osteoporosis.Citation: Ann Rheum Dis, volume 66, supplement II, year 2007, page 117Session: Management of osteoporosis