Renal function predicts 12-month response to romosozumab readministration after denosumab in women with osteoporosis

Lower estimated glomerular filtration rate (eGFR) independently predicted greater increases in lumbar spine and total hip bone mineral density after romosozumab readministration following denosumab. An eGFR cutoff of 54 mL/min/1.73 m² may guide patient selection for romosozumab readministration. However, further studies are needed to validate our results.

This study investigated whether renal function is an independent predictor of bone mineral density (BMD) increase during romosozumab readministration after denosumab in women with osteoporosis.

A multicenter study was conducted involving 31 Japanese women with osteoporosis who received romosozumab readministration between March 2019 and July 2024 following initial 12-month romosozumab treatment and sequential denosumab therapy. The estimated glomerular filtration rate (eGFR) at baseline and percent changes in lumbar spine (LS) and total hip (TH) BMD from baseline to 12 months were investigated. Multivariate regression analyses were performed to assess the association between renal function and BMD, adjusting for all previously reported potential confounders, including secondary osteoporosis, age, denosumab duration, BMD, and bone turnover makers. Receiver operating characteristic (ROC) curves were used to determine eGFR cutoff values predicting ≥ 3% BMD increase (i.e., treatment response).

Approximately 38.7% and 19.4% of patients achieved ≥ 3% increase in LS and TH BMD at 12 months, respectively. Lower eGFR was significantly associated with greater LS (adjusted β =  - 0.14, 95% confidence interval [CI] - 0.27 to - 0.01) and TH BMD increases (adjusted β =  - 0.10, 95% CI - 0.18 to - 0.01). The optimal eGFR cutoff value predicting LS or TH response was 54.1 mL/min/1.73 m², with 64.3% sensitivity and 94.1% specificity (area under the ROC curve 0.77).

Lower baseline eGFR was an independent predictor of greater LS or TH BMD response to romosozumab readministration after denosumab, with an optimal cutoff value of 54 mL/min/1.73 m². Larger studies are needed to validate these findings.