How different is the once-weekly teriparatide from the daily one or the same?

Improvement in Glucocorticoid-Induced Osteoporosis on Switching from Bisphosphonates to Once-Weekly Teriparatide: A Randomized Open-Label Trial

This randomized, open-label, multicenter, parallel study imitating real-world clinical practice assessed the effect of switching to weekly teriparatide in patients with glucocorticoid-induced osteoporosis (GIO) with a lumbar spine/proximal femur bone mineral density (BMD) T-score ≤ -2.0 or ≤-1.0 and a fragility fracture. Forty-four patients were randomized. The mean durations of the corticosteroid and bisphosphonate administrations were 90.0 and 51.3 months. The baseline BMD at L1-L4 was 0.828 and 0.826 g/cm² in Groups B (bisphosphonate) and T (teriparatide); at the femur (total), these values were 0.689 and 0.661 g/cm². The mean change in BMD was numerically higher with teriparatide vs. bisphosphonate but not statistically significant. The mean percentage changes from baseline in BMD at L1-L4 after a 72-week treatment were 0.5% and 4.1% in Groups B and T. The incidence of new fractures was higher in the patients taking bisphosphonates vs. those receiving once-weekly teriparatide at 72 weeks (18.2% vs. 11.8%) and 144 weeks (22.7% vs. 17.6%). The mean percentage change in femur (trochanter) BMD (0.035 [0.007-0.063]; p = 0.02) was significantly greater with teriparatide vs. bisphosphonates. Adverse events (AEs) were more frequent with teriparatide vs. bisphosphonates. Switching to once-weekly teriparatide tended to increase lumbar spine BMD and reduce the occurrence of new fractures vs. bisphosphonates.

Efficacy of once-weekly teriparatide for primary prevention of glucocorticoid-induced osteoporosis: A post hoc analysis of the TOWER-GO study

OBJECTIVES

A post hoc analysis of the Teriparatide Once-Weekly Efficacy Research for Glucocorticoid-induced Osteoporosis (TOWER-GO) study was performed to examine the effect of once-weekly administration of 56.5 μg teriparatide on primary prevention of glucocorticoid-induced osteoporosis (GIOP).

METHODS

Of the subjects of the TOWER-GO study, 73 were included. The percentage changes from baseline in lumbar spine bone mineral density (BMD) and bone turnover markers were evaluated over 72 weeks with once-weekly teriparatide and once-weekly alendronate.

RESULTS

The percentage change of lumbar spine BMD from baseline at 72 weeks was significantly increased in both groups. Bone formation markers were significantly increased by teriparatide administration, although they were slightly decreased by alendronate administration. Bone resorption markers were gradually decreased by teriparatide, whereas alendronate markedly decreased them within 4 weeks. No major safety concerns arose.

CONCLUSIONS

In this primary prevention study of GIOP, comparable increases in BMD were observed between alendronate and once-weekly teriparatide. More desirable changes in bone markers were observed with teriparatide administration. These data suggest that once-weekly teriparatide is effective in primary prevention of GIOP.

Efficacy of once-weekly teriparatide in patients with glucocorticoid-induced osteoporosis: the TOWER-GO study

INTRODUCTION

Bisphosphonates are the standard treatment for glucocorticoid-induced osteoporosis (GIOP) with teriparatide being another option. While daily teriparatide has been shown to be effective in increasing bone mineral density (BMD), the efficacy of once-weekly teriparatide (56.5 µg) has not yet been evaluated. The TOWER-GO study, a 72-week, multicenter, open-label, randomized controlled trial, was conducted in patients with GIOP to compare the effects of once-weekly teriparatide and once-weekly alendronate 35 mg on BMD.

MATERIALS AND METHODS

Patients (N = 180) with GIOP for whom drug treatment was indicated according to the 2004 guidelines in Japan were randomized to receive once-weekly teriparatide (n = 89) or once-weekly alendronate (n = 91). The primary endpoint was the non-inferiority of percentage change in lumbar spine BMD at final follow-up. The secondary endpoints were the percentage change in BMD from baseline, incidence of bone fractures, and changes in bone turnover markers.

RESULTS

While the non-inferiority of teriparatide to alendronate was not confirmed, BMD increased significantly from baseline with teriparatide and alendronate by 5.09% and 4.04%, respectively (both p < 0.05), at 72 weeks. The incidence of vertebral and non-vertebral fractures was similar in both groups. Bone formation markers increased in the teriparatide group and decreased in the alendronate group.

CONCLUSIONS

The non-inferiority of once-weekly teriparatide versus once-weekly alendronate in BMD change at 72 weeks was not shown, but the increase in bone formation markers over time and the increase of BMD in GIOP patients treated with once-weekly teriparatide were confirmed.