Ab0554 Cliniclal Efficacy of Sequential Treatment After Romosozumab in Patients With Rheumatoid Arthritis Comparison With Primary Osteoporosis for 24 Months

Background: Romosozumab (ROMO), a monoclonal antibody that binds sclerostin, increases bone formation and decreases bone resorption. And although it is a novel therapeutic agent for osteoporosis, which has shown high effects of increasing bone density and inhibiting fragile fracture in overseas clinical trials. However the clinical efficacy for rheumatoid arthritis complicated with osteoporosis (RA-OP) is unknown. Objectives: To evaluate the clinical efficacy of ROMO for 12 months and denosumab (DMB) for 12 months in patients with RA-OP comparison with primary osteoporosis (P-OP) for 24 months. Methods: RA patients diagnosed according to the 2010 ACR/EULAR criteria. All patients (RA-OP; 12 cases, P-OP; 19 cases) met at least one of the following criteria were eligible; a bone mineral density T score of -2.5 or less at the lumber spine or total hip and either one or more moderate or severe vertebral fractures or two or more mild vertebral fractures. All patients were initiated ROMO from between April, 2019 and July, 2020. The ROMO dose was 210mg at once every 1 months. After 12 months of ROMO, all cases were changed to DMB. In all cases native or activated vitamin D has been used. We reviewed the results for 24 months about the increase and decrease of bone mineral density (BMD) of lumbar spine(LS) and total hip(TH) by DEXA and bone turnover markers, intact n-terminal propeptide type I procollagen(PINP) and tartrate-resistant acid phopshatate form 5b(TRACP-5b). Results: The gender was all female. Patient background at baseline in RA-OP (n=16) and P-OP (n=23) had a mean age of 71.4 ± 7.9 and 74.3 ± 8.9 (p=0.130); the body mass index were 19.4 ± 2.6 and 19.8 ± 3.6 (p=0.475); the FRAX were 36.0 ± 14.9 and 32.7 ± 16.4 (p=0.394); the number of previous fracture were 5cases (31%) and 16cases (70%) (p=0.018) and the number of previous drug for treatment osteoporosis use were 9cases (56%) and 9cases(39%) (p=0.292). The bone turnover markers and bone mineral density at baseline were as follows; P1NP 62.4 ± 32.1 and 85.8 ± 94.1 (p=0.932); TRACP-5b 467 ± 228 and 542 ± 272 (p=0.424); LS-BMD and T-score 0.79 ± 0.13 and 0.78 ± 0.12 g/cm² (p=0.797), -2.83 ± 0.91 and -2.88 ± 0.86 (p=0.808) and TH-BMD 0.56 ± 0.07 and 0.57 ± 0.07 g/cm² (p=0.560), -3.11 ± 0.52 and -3.03 ± 0.51 (p=0.590). Clinical findings related to RA-OP at baseline were as follows; disease duration 14.7 ± 15.7 years; CRP 1.99 ± 2.98; DAS28-CRP 3.60 ± 1.45; HAQ 1.56 ± 0.99. The rate of increased LS-BMD from baseline to 6, 12, 18 and 24 months between RA-OP and P-OP were 11.2 ± 7.0% and 11.1 ± 5.6%, (p=0.943) at 6 monts, 15.5 ± 8.7% and 16.5 ± 8.4% (p=0.627) at 12 months, 19.3 ± 9.4% and 22.4 ± 9.8% (p=0.797) at 18 months, 20.3 ± 10.9% and 22.4 ± 9.8% (p=0.732) at 24 months and TH-BMD were 4.1 ± 3.9% and 2.9 ± 3.8%, (p=0.310) at 6 monts, 6.2 ± 5.8% and 6.5 ± 5.9% (p=0.893) at 12 months, 8.9 ± 7.9% and 7.9 ± 5.2% (p=0.976) at 18 months, 9.2 ± 9.4% and 9.0 ± 4.8% (p=0.362) at 24 months. Conclusion: Clinical efficacy of treatment with ROMO for 12months and DMB for 12months was extremely effective for RA-OP as well as for P-OP and has the high potential to be an important option in the treatment of RA-OP. REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests: None declared.