ODP119 Raloxifene use after denosumab discontinuation partially attenuates bone loss in the lumbar spine in postmenopausal osteoporosis

PURPOSE: Discontinuation of denosumab (DMab) is associated with rapid declinein bone density. Sequential antiresorptive drugs are recommended to preserve bone mass after DMab treatment. It remains unclear whether raloxifene exclusively can be used in certain conditions to attenuate bone loss after DMab discontinuation. METHODS: In this retrospective cohort study, data on postmenopausal women with osteoporosis who discontinued DMab treatment after short-term use (at Severance Hospital, Seoul, Korea, between 2017 and 2021) were reviewed. Changes in bone mineral density (BMD) at 12 months after DMab discontinuation was compared between sequential raloxifene users (DR) and control group without any sequential lantiresorptive (DD). Baseline characteristics were matched through 1: 1 propensity score matching (PSM) without replacement. RESULTS: A total of 66 patients (DR n=33; DD n=33) were studied. In propensity score matched cohort, mean age was 69.3 ± 8.2 years and T-score for lumbar spine and total hip was -2.2 ± 0.7 and -1.6 ± 0.6, respectively, at the time of DMab discontinuation. Common reason for DMab discontinuation or sequential treatment to raloxifene was invasive dental surgery in DR (n=18, 55%) and ineligibility to obtain insurance reimbursement due to improved BMD in DD (n=18, 55%). Raloxifene caused attenuation of BMD loss (-2.78% vs. -5.80%, p=0. 013)of lumbar spine after adjusting for age, BMI, previous fracture history, lumbar spine T-score at the time of DMab discontinuation, prior bisphosphonate exposure, and DMab injection time. CONCLUSION: Raloxifene use after short-term DMab treatment (less than 2.5 years) attenuated lumbar spine BMD loss in postmenopausal women. Presentation: No date and time listed