Romosozumab Effective in RA and Primary Osteoporosis: Study

Patients with RA-OP and P-OP were included in the study if they had a BMD T score of -2.5 or less at the lumbar spine or hip and either 1 or more moderate or severe vertebral fractures or 2 or more mild vertebral fractures. All patients received 210 mg romosozumab once per month for more than 6 months. Researchers measured BMD and T-scores of the lumbar spine and hip and bone turnover markers including procollagen I N-terminal propeptide (PINP) and tartrate-resistant acid phosphatase 5b (TRACP-5b) during the 12-month study period.

Among 48 patients (14 with RA-OP and 34 with P-OP), 47 were women. Mean age of patients was 73.4±9.3 years, with a body mass index of 20.4±3.8 and high fracture risk assessment (FRAX) scores of 36.4±16.8. Duration of RA in patients with RA-OP was 19.9±16.4 years. Baseline RA indices for patients with RA-OP included C-reactive protein (CRP) 0.58±0.59, disease activity score (DAS28-CRP) 3.39±0.93, and health assessment questionnaire disability index (HAQ) 1.63±0.94. Baseline bone measurements for all patients were PINP 83.2±77.9, TRACP-5b 525±291, lumbar spine BMD 0.79±0.15 g/cm2, lumbar spine BMD T-score -2.80±1.03, hip BMD 0.57 ± 0.08 g/cm2, and hip BMD T-score -3.04±0.62. Over a period of 12 months, the researchers observed a decrease in TRAC-5b biomarker levels and increase in PINP and BMD (lumbar and hip) from baseline.

The results of the study are as follows:

The rate of decrease in TRAC-5b from baseline to 1, 3, 6 and 12 months was -19.4%±25.3%, -10.0%±31.6%, -8.9%±51.8%, and -11.6%±60.2%, respectively.

• The rate of increase in PINP from baseline to 1, 3, 6 and 12 months was 105.2%±90.8%, 87.3%±100.7%, 66.5%±143.1%, and 30.8%±146.6%, respectively.
• The rate of increase in lumbar spine BMD from baseline to 6 and 12 months was 10.3%±7.3% and 14.6%±9.9%, respectively.
• For hip BMD, the rate of increase from baseline to 6 and 12 months was 3.8%±5.6% and 6.6%±7.8% respectively.

Thus, the researchers concluded that clinical efficacy of romosozumab for RA-OP and P-OP was extremely effective for 12 months and has the high potential to be an important option in the treatment of osteoporosis."

Reference

Kanayama Y, Tsuji T, Futamura N, Ota K, Watanabe T, Teresawa K, Maeda K. Clinical efficacy of romosozumab in patients with rheumatoid arthritis and primary osteoporosis for 12 months. Presented at: ASBMR Annual Meeting 2021; October 1-4, 2021; San Diego, CA. Abstract VPP-647.