Effects of follow-on therapy after denosumab discontinuation in patients with postmenopausal osteoporosis.

OBJECTIVES

To clarify the effects of follow-on therapy after denosumab (DMAb) discontinuation.

METHODS

In this retrospective, multicenter study, postmenopausal patients with osteoporosis who were previously treated by oral bisphosphonates (BP) (n = 26) or teriparatide (TPTD) (n = 27) were switched to DMAb (administered 2.6 times), and then discontinued. Patients (73.1 years, T-scores of the lumbar spine [LS] - 2.7 and femoral neck [FN] - 2.2) were switched to either (1) raloxifene (RAL) (n = 13) or BP [(2) weekly or monthly BP (wmBP) (n = 29) or (3) zoledronate (ZOL) (n = 11)], based on each physician's decision (mean interval after final DMAb administration was 7.2 months). Bone mineral density (BMD) at final DMAb administration were set as baseline.

RESULTS

Changes in LS BMD at 1.5 years after final DMAb administration were -2.7% in the RAL, 0.7% in the wmBP, and 1.9% in the ZOL (p = .31 between groups), and in FN BMD were -3.8%, -0.8%, and 1.8%, respectively (p = .02 between the RAL and ZOL; p = .048 between the RAL and BP). Clinical vertebral fracture incidence during 1.5 years after final DMAb administration was 23.1% in the RAL, 3.4% in the wmBP, and 0.0% in the ZOL (p = .048 between the RAL and ZOL; p = .015 between the RAL and BP). No significant differences were observed in these parameters between the wmBP and ZOL.

CONCLUSION

These results may contribute to the selection of adequate follow-on therapy after DMAb discontinuation, although further investigations are required.