Introduction: Effective treatment of postmenopausal osteoporosis (PMO) is frequently compromised by poor adherence to short-term (≤1-monthly) medications. Aim of this study is to investigate the effect of parenteral ibandronate (IBN) compared to denosumab in a cohort of IBN pretreated PMO patients.
Methods: In a retrospective analysis, a total of 808 women were treated with quarterly 3 mg IBN injections for 27+3 months and were regularly monitored at the osteoporosis outpatient clinic at two large academic centers. After denosumab became available, 366 women were switched to receive this therapy due to their own and their physicians decision, whereas the remaining 442 preferred to stay on IBN. Fracture incidence, BMD, BTM, and adherence/safety of these two parenteral therapies will be analyzed.
Results: Important baseline characteristics are given in the Table 1. There were no differences in any of the parameters investigated including renal and liver function, vitamin D, PTH and bone turnover markers. Laboratory testing, recording of adverse events was done every 6 months, BMD readings, spinal X-ray and fracture assessment were performed at baseline and after 12 and 24 months of ongoing IBN or denosumab therapy.
|Denosumab (n=366)||Ibandronate (n=442)|
|Femoral neck BMD (T-score)||−2.1+0.9||−2.0+1|
|Lumbar spine BMD (T-score)||−2.8+1.2||2.7+1.4|
|Non-vertebral fracture, n (%)||26 (7.1%)||34 (7.7%)|
|Vertebral fracture, n (%)||69 (18.9%)||84 (19%)|
Conclusion: The results of this study not only will provide clinicians with insight into persistence with denosumab in comparison to quarterly IBN therapy, but will also compare the effect of denosumab for the first time with a parenteral administered bisphosphonate in respect to safety, changes in BMD as well as fracture incidence and changes in SDI over a time period of 2 years.
17 May 2014 - 20 May 2014