Probability of achieving bone mineral density treatment goals with denosumab treatment in postmenopausal women with osteoporosis

BMD levels achieved on osteoporosis treatment are predictive of subsequent fracture risk, and T-score >-2.5 has been proposed as a minimum treatment target for women with osteoporosis. Knowing the likelihood of attaining target T-scores with different medications for different baseline BMD levels can help determine appropriate initial treatment for individual patients. In this post hoc analysis, we estimated the probability of achieving a non-osteoporotic T-score (>-2.5 or ≥-2.0) at the TH or LS in postmenopausal women >60 yr old treated with denosumab for either 3 or 10 yr in the FREEDOM trial and its long-term extension. In women with baseline TH T-scores of -2.7, -3.0, and -3.5, the probabilities of achieving target T-scores >-2.5 with 3 yr of denosumab were 71%, 12%, and 0.1%, respectively. At LS, for baseline T-scores of -2.7, -3.0, and -3.5, the probabilities were 86%, 59%, and 11%, respectively. Longer treatment duration of up to 10 yr increased the probability of achieving target T-scores. The baseline T-scores that permitted at least 50% of women to achieve a target T-score >-2.5 were -2.8 at TH and -3.1 at LS after 3 yr and -3.0 at TH and -3.7 at LS after 10 yr of treatment. To achieve higher treatment targets (T-scores ≥ -2.0), overall probabilities were lower at both skeletal sites, particularly for TH, even with longer treatment duration. Our results demonstrate that the probability of achieving T-score targets with denosumab is dependent on baseline BMD, skeletal site, and treatment duration. Knowing the probability of achieving treatment targets for different baseline TH and LS T-scores can help determine whether denosumab is an appropriate first choice of treatment in individual patients.