Study design of multi-center, open-label randomized controlled, head-to-head trial comparing minodronic acid and raloxifene: Japanese Osteoporosis Intervention Trial (JOINT)-04

Effect of Bone Resorption Inhibitors on Serum Cholesterol Level and Fracture Risk in Osteoporosis: Randomized Comparative Study Between Minodronic Acid and Raloxifene

The positive link between osteoporosis and hypercholesterolemia has been documented, and bone resorption inhibitors, such as nitrogen-containing bisphosphonates (N-BP) and selective estrogen receptor modulators (SERMs), are known to reduce serum cholesterol levels. However, the relationship between the baseline cholesterol level and incident fracture rate under the treatment using the bone resorption inhibitors has not been documented. We investigated the relation between vertebral fracture incident and the baseline cholesterol levels and cholesterol-lowering effect of N-BP and SERM in osteoporosis through a prospective randomized open-label study design. Patients with osteoporosis (n = 3986) were allocated into two groups based on the drug used for treatment: minodronic acid (MIN) (n = 1624) as an N-BP and raloxifene (RLX) as an SERM (n = 1623). Serum levels of cholesterol and incidence of vertebral fracture were monitored for 2 years. The vertebral fracture rates between the two groups were compared using the pre-specified stratification factors. The patients receiving MIN with baseline low-density lipoprotein (LDL)-cholesterol level of ≥ 140 mg/dL, high-density lipoprotein cholesterol level < 40 mg/dL, age group of ≥ 75 years, and T score of BMD ≥ -3 SD had significantly lower vertebral fracture rates than those receiving RLX (incidence rate ratios (IRR) 0.45 [95% confidence interval (CI) 0.30 0.75, p = 0.001], 0.25 [95% CI 0.09 0.65, p = 0.005], 0.71 [95% CI 0.56 0.91, p = 0.006], 0.47 [95% CI 0.30 0.75, p = 0.0012], respectively). The cholesterol-lowering effect was stronger in the RLX group than in the MIN group, regardless of prior statin use. These results indicated that MIN treatment was more effective in reducing fracture risk in patients with higher LDL cholesterol levels, although its cholesterol-lowering ability was lesser than the RLX treatment.Trial registration University Hospital Medical Information Network-Clinical Trials Registry (UMIN-CTR), No. UMIN000005433; date: April 13, 2011.

Influence of symptomatic periodontal disease on changes in skeletal bone density during medication therapy for osteoporosis in postmenopausal women: the Japanese Osteoporosis Intervention Trial (JOINT)-04 and JOINT-05

Japanese postmenopausal women with symptomatic periodontal disease had a significantly smaller increase in the T-score for total hip bone density than those without periodontal disease during medication therapy for osteoporosis. Intervention to treat symptomatic periodontal disease before and/or during osteoporosis therapy could maintain the effect of osteoporosis medications.

PURPOSE

Women with periodontal disease may be more likely to develop osteoporosis. We evaluated whether the presence of symptomatic periodontal disease can influence changes in skeletal bone mineral density (BMD) during medication therapy for osteoporosis in Japanese postmenopausal women.

METHODS

A total of 4,258 postmenopausal women participated in the Japanese Osteoporosis Intervention Trial protocol number 4 (JOINT-04 trial) and number 5 (JOINT-05 trial), which were multi-center, open-label, randomized controlled trials in Japan. Of these, 3,670 non-edentulous subjects participated in the study. Subjects who had self-reported symptoms of periodontal disease at baseline were defined as having periodontal disease. The study outcome was the difference in BMD changes during the study between subjects with and without periodontal disease. Mixed models for repeated measures after adjusting for covariates were used to investigate the difference in the BMD changes during the study between subjects with and without periodontal disease.

RESULTS

Subjects with periodontal disease had significantly lower T-scores for total hip (p = 0.035) and metacarpal (p = 0.048) BMD than those without periodontal disease at baseline. During medication therapy for osteoporosis, subjects with periodontal disease had a significantly smaller increase in T-score for total hip BMD than those without periodontal disease (p = 0.021), although no significant differences were observed in the changes in T-scores for other skeletal BMD measurements between subjects with and without periodontal disease.

CONCLUSIONS

The presence of self-reported symptoms of periodontal disease may be associated with a decrease in the effect of osteoporosis medications in Japanese postmenopausal women.

Risk factors for incident vertebral fractures in osteoporosis pharmacotherapy: a 2-year, prospective, observational study

INTRODUCTION

To identify predictors for incident fractures in patients on pharmaceutical treatment for osteoporosis by a secondary analysis of the Japanese Osteoporosis Intervention Trial protocol number 4 (JOINT-04), which was a 2-year, randomized, parallel-group, controlled trial of minodronate and raloxifene in women with primary osteoporosis.

MATERIALS AND METHODS

This was a prospective, observational study using JOINT-04 data, in which biomarkers, such as undercarboxylated osteocalcin (ucOC), N-telopeptide of type 1 collagen, tartrate-resistant acid phosphatase 5b (TRACP-5b), bone alkaline phosphatase, homocysteine, and pentosidine in blood, and physical functions, such as the timed up and go test and one-leg standing test with eyes open (OLST), and the fall risk index, were measured. The relationships of incident morphometric vertebral fractures during the treatment period, as well as prevalent vertebral fractures, and baseline data were analyzed.

RESULTS

The full analysis set of the JOINT-04 included 3247 patients (1623 in the minodronate group and 1624 in the raloxifene group). The hazard ratio (95% confidence interval) for incident vertebral fractures over 2 years of pharmacotherapy, adjusted for confounders, was 0.93 (0.90-0.96) for ucOC, 1.15 (1.08-1.23) for TRACP-5b, 1.02 (1.01-1.03) for pentosidine, 0.91 (0.88-0.94) for the OLST, and 1.27 (1.01-1.60) for the fall risk index, which were all independent predictors.

CONCLUSION

Evaluating fracture risk for patients with osteoporosis considering these potential risk factors for fracture in addition to the established risk factors may be useful when starting pharmaceutical treatment.

Randomized head-to-head comparison of minodronic acid and raloxifene for fracture incidence in postmenopausal Japanese women: the Japanese Osteoporosis Intervention Trial (JOINT)-04

AIMS

We conducted a head-to-head randomized trial of minodronate, a bisphosphonate, and raloxifene, a selective estrogen receptor modulator, to obtain clinical evidence and information about their efficacy and safety.

METHODS

The Japanese Osteoporosis Intervention Trial protocol number 4 (JOINT-04) trial is a multi-center, open-labeled, blinded endpoints, head-to-head randomized trial of minodronate and raloxifene. Ambulatory elderly women with osteoporosis (age, >60 years) were randomly allocated to the raloxifene or minodronate group by central registration. The co-primary endpoints included any one of osteoporotic fractures (vertebral, humeral, femoral, and radial fractures), vertebral fractures, and major osteoporotic fractures (clinical vertebral, humeral, femoral, and radial fractures). The biological effects of each drug, patients' quality of life, and drug safety were assessed based on the secondary outcomes. This study was registered at the University Hospital Medical Information Network-Clinical Trials Registry (UMIN-CTR) under trial identification number UMIN000005433.

RESULTS

A total of 3896 patients were randomized to the minodronate and raloxifene groups, and drug efficacy assessments were performed for 3247 patients (1623 and 1624 patients, respectively). Among these patients, 1176 and 1187 patients received allocated treatment for 2 years. The incidence rate ratios for osteoporotic, vertebral, and major osteoporotic fractures in the minodronate group were 0.94 (95% CI: 0.78-1.13, p = .494), 0.86 (95% CI: 0.70-1.05, p = .147), and 1.22 (95% CI: 0.86-1.74, p = .274), respectively. Compared to the raloxifene group, the minodronate group showed significantly increased bone mineral density of the lumbar spine for each visit (6 months: p = .007, 12 months: p = .0003, 24 months: p<.0001). Also, serious adverse reactions were observed for four and six patients in the minodronate and raloxifene groups, respectively.

CONCLUSIONS

Overall, there were no statistical differences in the incidence rates of osteoporotic, vertebral, or major osteoporotic fractures between the two groups. Serious adverse reactions were rare in both groups.

Incidence of osteonecrosis of the jaw in Japanese osteoporosis patients taking minodronic acid

Osteonecrosis of the jaw (ONJ) associated with bisphosphonate therapy is a rare but severe side effect in osteoporosis patients. Recently, the number of osteoporosis patients with ONJ has dramatically increased in Japan. This has contributed to an increase in the number of patients avoiding extractions. However, there has been no prospective study providing definitive incidence data for ONJ in Japanese patients. The purpose of this study was to elucidate the true as well as suspected incidence of ONJ. A total of 3229 subjects (1612 subjects in the minodronic acid group and 1617 subjects in the raloxifene group) in the Japanese Osteoporosis Intervention Trial protocol number 4 participated in this study. ONJ was diagnosed by experienced dentists. Suspected Stage 0 and 1 (bone exposure of the jaw) ONJ was assessed by a structured questionnaire at baseline and at 6, 12, 18, and 24 months. No established ONJ cases were diagnosed during the study. The incidence of suspected Stage 0 and/or Stage 1 ONJ was 6.14 per 1000 patient-years in the minodronic acid group and 3.38 per 1000 patient-years in the raloxifene group [hazard ratio (95% confidence interval) = 1.82 (0.84-3.93), P = 0.13]. Approximately 50-60% of bone exposures that appeared during the study had disappeared at the next observation. Although the subjects in this study may have developed a greater interest in the health of the oral cavity, the incidence of ONJ after minodronic acid treatment would be lower than the expected incident rate.