Abstract
Abaloparatide treatment significantly increased BMD at the LS, TH, and FN compared with placebo in men with osteoporosis in the phase 3 ATOM trial. The current study used 3D-DXA modeling to evaluate the effects of abaloparatide on cortical and trabecular compartments of the proximal femur in ATOM study participants. Proximal femur DXA images were retrospectively analyzed using 3D-DXA (3D-Shaper software v2.12.0, 3D-Shaper Medical, Barcelona, Spain) to evaluate changes in bone parameters from baseline at months 6 and 12 in all randomized men from the ATOM trial. Between-group comparisons were made for percent change from baseline data based on a mixed-effect repeated-measure model with treatment, visit, treatment-by-visit interaction, and type of DXA scanner as fixed effects. Other covariates include BMI, age, and baseline values of bone parameters. Abaloparatide treatment significantly increased integral volumetric BMD (vBMD) (3.7%), trabecular vBMD (7.0%), cortical thickness (1.1%), and cortical surface BMD (1.7%) at 12 mo compared to baseline (p < .0001). Changes were greater for abaloparatide compared to placebo for all 4 parameters (p < .01). Significant increases from baseline compared to placebo in integral vBMD (2.7% vs -0.1%, p < .0001) and trabecular vBMD (6.1% vs -0.6%, p < .0001) were also observed at 6 mo. In conclusion, in men with osteoporosis, abaloparatide improved proximal femur 3D-DXA parameters broadly consistent with results in postmenopausal women in the ACTIVE study, adding to the growing data on abaloparatide bone structure effects at the hip.