NEW YORK (Reuters Health) – The bone anabolic drug teriparatide is more effective than alendronate at increasing bone mineral density (BMD) and preventing vertebral fractures in patients with glucocorticoid-induced osteoporosis, new research indicates.
In the November issue of Arthritis and Rheumatism, Dr. Kenneth G. Saag from the University of Alabama in Birmingham and co-investigators explain that patients taking steroids have an increased risk of fracture at all levels of bone density, which suggests their bone quality is at least somewhat impaired.
Teriparatide, a recombinant human parathyroid hormone, would improve pathologic changes in bone, they believed.
Their 36-month randomized, double-blind trial in 13 countries involved 428 patients who had taken prednisone or its equivalent at a dosage of at least 5 mg/day for 3 months or longer. Participants were assigned – 214 in each group — to take either injectable teriparatide (20 mcg/d) plus oral placebo, or oral alendronate (10 mg/d) plus injectable placebo. They were also given calcium supplements (1000 mg/d) and vitamin D (800 IU/d).
One hundred twenty-patients in the teriparatide group and 118 in the alendronate group completed both the 18-month primary phase and the 18-month continuation phase. The authors note, however, that “analyses were conducted on data from all randomized and treated subjects.”
The mean increases from baseline in lumbar spine, total hip, and femoral neck BMD were significantly greater in the teriparatide group than in the alendronate group at each time point (12, 18, 24, and 36 months, plus 3 and 6 months for lumbar spine).
Using a last observation carried forward analysis, at 36 months the mean increases in BMD from baseline for the teriparatide and alendronate groups, respectively, were 11.0% vs. 5.3% for the lumbar spine, 5.2% vs 2.7% for total hip, and 6.3% vs 3.4% for the femoral neck (p < 0.001 for all).
Mean changes were not affected by the underlying disease requiring glucocorticoid treatment or by glucocorticoid dose at baseline or 36 months.
Teriparatide treatment was also associated with a lower rate of vertebral fractures (1.7% vs 7.7%, p = 0.007). There were no significant differences between groups in new nonvertebral fractures.
The investigators also report sustained increases in biomarkers of bone formation in the teriparatide group and sustained decreases in the alendronate group.
Rates of adverse events, serious adverse events, or possibly treatment-related adverse events did not differ between the groups.
According to the authors, “Teriparatide is efficacious and generally well tolerated for treating subjects with glucocorticoid-induced osteoporosis and should be considered as a therapeutic option for subjects at high risk of fracture.”
Arthritis Rheum 2009; 60:3346-3355.