Compliance and discontinuation of denosumab treatment in postmenopausal Japanese women with primary osteoporosis or rheumatoid arthritis and osteoporosis

OBJECTIVES: The aim of this study was to examine the discontinuation and occurrence of fracture during denosumab treatment in Japanese women with primary osteoporosis or rheumatoid arthritis (RA) with osteoporosis. METHODS: This retrospective study included 143 patients with primary osteoporosis and 96 patients with RA and osteoporosis who were treated with denosumab. Treatment discontinuation, fracture occurrence, lumbar spine (L1–4) bone mineral density (LS-BMD), and bilateral total hip BMD (TH-BMD) were examined before and at 1 and 2 years after treatment commencement. RESULTS: In the primary osteoporosis group, 32 cases dropped out and no fractures occurred from 0 to 1 year. Eighteen cases were lost to follow-up and no fractures were noted from 1 to 2 years. In the RA with osteoporosis group, 7 cases dropped out and no fracture occurred from 0 to 1 year. Twenty-one cases were lost to follow-up and 2 nonvertebral fractures were noted from 1 to 2 years. In this group, 13 cases dropped out from 1 to 2 years and 16 cases dropped out during the 2-year study period due to economic reasons. LS-BMD and TH-BMD values increased continuously for 2 years of treatment in both primary osteoporosis and RA with osteoporosis groups. CONCLUSIONS: These results suggest that during denosumab therapy, the discontinuation rate is expected to remain low during 2 years of treatment in primary osteoporotic patients. In RA patients with osteoporosis, however, the discontinuation rate may increase due to economic reasons from 1 to 2 years of therapy.

Monthly minodronate inhibits bone resorption to a greater extent than does monthly risedronate

As a bisphosphonate, minodronate (MIN) is one of the strongest inhibitors of bone resorption. However, there have been no reports directly comparing the antiresorptive effects of monthly MIN with those of monthly risedronate (RIS). We enrolled 30 cases of osteoporosis (OP; 16 in the MIN group [mean age: 68.2 years] and 14 in the RIS group [mean age: 68.1 years]) to investigate the early effects of treatment by monthly MIN or RIS over a 4-month period using bone turnover marker values. Only female patients were enrolled to avoid gender bias. Urinary cross-linked N-telopeptide of type I collagen (NTX) before treatment and at 1, 2, and 4 months of therapy, as well as serum bone alkaline phosphatase and alkaline phosphatase before treatment and at 4 months afterwards, were evaluated. All bone turnover marker values were significantly decreased at 4 months in both groups. The changes in urinary NTX at the study end point for RIS and MIN were -30.1% and -63.1%, respectively. From 2 months of treatment, the antiresorptive effects on urinary NTX by MIN were significantly higher than those by RIS, indicating that MIN more immediately and strongly inhibited bone absorption. Thus, monthly MIN seems to suppress bone resorption faster and more strongly than RIS in OP treatment.