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.

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

We planned to conduct multi-center, open-labeled, blinded-endpoints, head-to-head randomized trial of minodronate and raloxifene to compare incidences of vertebral and non-vertebral fractures. The study is the Japanese Osteoporosis Intervention Trial protocol number 4 (JOINT-4). Here, we present the pre-fixed study design. The inclusion criteria are ambulatory older women with osteoporosis, aged > 60 years, and without pre-specified risk factors for secondary osteoporosis and dementia. The subjects who meet selection criteria will be randomly allocated to the raloxifene (60 mg/day) or minodronate (1 mg/day or 50 mg/4 weeks) groups using the central registry. The co-primary endpoints are osteoporotic (vertebral, humeral, femoral, and radial), vertebral, and major osteoporotic (clinical vertebral, humeral, femoral, and radial) fractures. Furthermore, we plan to use the Hochberg procedure to preserve an overall type 1 error rate. In addition, changes in bone mineral density (BMD), hip-structure analysis (HSA) variables, height, bone turnover markers, serum cholesterol and triglyceride concentrations, dental health questionnaire, fall frequency, fall risk index, nursing care level, physical function, quality of life (QOL), and safety profiles were assessed as secondary endpoints. To detect 24% reduction of major osteoporotic fractures with 80% power and a two-sided significance level of 5% with a 2-year observation period, 1734 patients/treatment arm would be required. Subgroup analysis stratified to the following factors age, body mass index, BMD, 25-hydroxyvitamin D concentration, estimated glomerular filtration rate (eGFR), prevalent vertebral fracture number, hypertension status, and diabetes mellitus is pre-specified. The protocol is registered in the trial registry system, and the trial identification number is UMIN000005433.

Comparison of concurrent treatment with vitamin K2 and risedronate compared with treatment with risedronate alone in patients with osteoporosis: Japanese Osteoporosis Intervention Trial-03.

The aim of this study was to investigate the efficacy of concurrent treatment with vitamin K2 and risedronate compared with treatment with risedronate alone in patients with osteoporosis and to explore subsets of patients for which concurrent treatment is particularly efficacious. Women with osteoporosis aged 65 years or older were recruited from 123 institutes in Japan and allocated to take either vitamin K2 (45 mg/day) and risedronate (2.5 mg/day or 17.5 mg/week) or risedronate (2.5 mg/day or 17.5 mg/week) alone. The primary end point was the incidence of any fracture (vertebral and nonvertebral). The secondary end points were bone mineral density, height, undercarboxylated osteocalcin concentration, quality of life, and safety. Over a 2-year follow-up, vertebral or nonvertebral fractures occurred in 117 or 22 sites respectively among 931 patients in the risedronate and vitamin K2 group and in 104 or 26 sites respectively among 943 patients in the risedronate alone group. The rates of any incident fracture were similar between the two groups (incidence rate ratio 1.074, 95 % confidence interval 0.811-1.422, p = 0.62), implying that the primary end point was not met. There were no differences in the degree of increase in bone mineral density between the two groups. Undercarboxylated osteocalcin concentration decreased from 5.81 ± 3.93 ng/mL to 2.59 ± 1.52 ng/mL at 6 months in the risedronate and vitamin K2 group, whereas the change in the risedronate alone group was minimal (from 5.96 ± 4.36 ng/mL to 4.05 ± 3.40 ng/mL at 6 months) (p < 0.01). The treatment discontinuation rate was higher in the risedronate and vitamin K2 group than in the risedronate alone group (10.0 % vs 6.7 %). No unknown adverse drug reactions were reported. In conclusion, concurrent treatment with vitamin K2 and risedronate was not efficacious compared with monotherapy with risedronate in terms of fracture prevention.

Impact of Osteonecrosis of the Jaw on Osteoporosis Treatment in Japan: Results of a Questionnaire-Based Survey by the Adequate Treatment of Osteoporosis (A-TOP) Research Group.

Dentists request a discontinuation of antiresorptive agents, such as bisphosphonate, before and after tooth extractions to prevent osteonecrosis of the jaw (ONJ). However, little is known about how this affects ONJ and osteoporosis treatment and how medical professionals and dentists cooperate to treat ONJ in patients with osteoporosis. This study aimed to clarify the impact of ONJ on osteoporosis treatment in Japan. A structured questionnaire including 14 key clinical queries was sent to 488 medical professionals as part of the Japanese Osteoporosis Intervention Trial (JOINT)-04, and 206 responses were received. A total of 173 respondents had received discontinuation requests from dentists. Of these, 28 respondents experienced 30 adverse events including ten fractures and one incidence of ONJ. The respondents who refused discontinuation requests observed no cases of ONJ. Approximately 16 % of respondents had patients who discontinued osteoporosis treatment, following a requested drug discontinuation, after tooth extraction. Dentists requested discontinuations for many medications that were not associated with the incidence of ONJ. Approximately 76 % of respondents had never requested oral health care from dentists before osteoporosis treatment and 72 % reported no cooperation between dentists and medical professionals in their region. Our results suggest that drug discontinuation may increase adverse events and disturb osteoporosis treatment without completely preventing ONJ. Currently, both medical professionals and dentists in Japan still continue to recommend their own treatment position. A forum to share information about ONJ among medical professionals, dentists, and patients is required.

Design of a randomized clinical trial of concurrent treatment with vitamin K2 and risedronate compared to risedronate alone in osteoporotic patients: Japanese Osteoporosis Intervention Trial-03 (JOINT-03).

Concurrent treatments with bisphosphonates and vitamin K are promising given that bisphosphonates possibly interfere with vitamin K activation. This is a prospective, multi-center, open-labeled, randomized trial of the efficacy of concurrent treatment with vitamin K2 and risedronate compared with risedronate alone and to explore subsets of patients for which concurrent treatment is particularly efficacious (trial identification number UMIN000000991). Inclusion criteria are women who meet the criteria for pharmacological therapy for osteoporosis, aged ≥65 years, have any of pre-specified risk factors, can walk unassisted, and are able to answer questionnaires. Exclusion criteria are prior warfarin use, secondary osteoporosis or non-osteoporotic metabolic bone diseases, contraindication for vitamin K2 and risedronate, hyper- or hypoparathyroidism, mental disorders, prevalent vertebral fracture at ≥6 sites, severe degenerative spinal deformation between T4 and L4, serious heart, liver, or kidney disease, or bisphosphonate use within the previous 6 months. Patients were recruited from 123 institutes between January 2008 and February 2010, and allocated to vitamin K2 (45 mg/day) and risedronate (2.5 mg/day or 17.5 mg/week) or risedronate alone (2.5 mg/day or 17.5 mg/week) groups. Primary endpoint is a vertebral or non-vertebral fracture. Secondary endpoints are bone mineral density, height, undercarboxylated osteocalcin, JOQOL, EQ-5D and safety. A sample size of 910 subjects per group and 2-year follow-up will provide 80 % power to detect 35 % risk reduction for fracture, with a two-sided significance level of 5 %. Subgroup analysis stratified to adjustment factors for random allocation, body mass index, 25-hydroxyvitamin D, estimated glomerular filtration rate, grade of vertebral fracture, JOQOL, EQ-5D, and co-morbidity is pre-specified.

[A-TOP research group/JOINT program].

A-TOP research consortium has been authorized at 2000 by the Japanese Society of Osteoporosis and assisted by Public Health Research Foundation in order to obtain the clinical evidences regarding osteoporosis treatment. Each clinical trial program was named as JOINT (Japanese Osteoporosis Intervention Trial), which was multi-center randomized open label trial and was registered into clinical trial registry. JOINT-02 was started at 2003 to confirm the effect of combination treatment of active vitamin D3 and alendronate in the prevention of osteoporotic bone fracture occurrence. This trial will be terminated at 2009 and the subsequent third clinical trial to obtain the evidence regarding the combination effects of risedronate and vitamin K2 as JOINT-03 project has been started from 2008. Each trial included around 2,000 participants mainly from practitioner and the registration of the cases in JOINT-02 has been finished within 3 years, suggesting that the participated practitioner would have sympathy with the research aims. The A-TOP research group would have carried out epidemiological studies regarding establishment of osteoporosis database (JOB study), which will contribute the additional knowledge of Japanese osteoporosis.