Odanacatib in the treatment of postmenopausal women with low bone mineral density: Three‐year continued therapy and resolution of effect

The selective cathepsin K inhibitor odanacatib (ODN) progressively increased bone mineral density (BMD) and decreased bone‐resorption markers during 2 years of treatment in postmenopausal women with low BMD. A 1‐year extension study further assessed ODN efficacy and safety and the effects of discontinuing therapy. In the base study, postmenopausal women with BMD T‐scores between ?2.0 and ?3.5 at the lumbar spine or femur received placebo or ODN 3, 10, 25, or 50 mg weekly. After 2 years, patients (n = 189) were rerandomized to ODN 50 mg weekly or placebo for an additional year. Endpoints included BMD at the lumbar spine (primary), total hip, and hip subregions; levels of bone turnover markers; and safety assessments. Continued treatment with 50 mg of ODN for 3 years produced significant increases from baseline and from year 2 in BMD at the spine (7.9% and 2.3%) and total hip (5.8% and 2.4%). Urine cross‐linked N‐telopeptide of type I collagen (NTx) remained suppressed at year 3 (?50.5%), but bone‐specific alkaline phosphatase (BSAP) was relatively unchanged from baseline. Treatment discontinuation resulted in bone loss at all sites, but BMD remained at or above baseline. After ODN discontinuation at month 24, bone turnover markers increased transiently above baseline, but this increase largely resolved by month 36. There were similar overall adverse‐event rates in both treatment groups. It is concluded that 3 years of ODN treatment resulted in progressive increases in BMD and was generally well tolerated. Bone‐resorption markers remained suppressed, whereas bone‐formation markers returned to near baseline. ODN effects were reversible: bone resorption increased transiently and BMD decreased following treatment discontinuation. © 2011 American Society for Bone and Mineral Research.     

Effects of Bazedoxifene on BMD and Bone Turnover in Postmenopausal Women: 2‐Yr Results of a Randomized,Double‐Blind,Placebo‐, and Active‐Controlled Study

Osteoporosis is an increasingly common health concern in postmenopausal women. In a 2‐yr phase III study, bazedoxifene prevented bone loss, reduced bone turnover, and was well tolerated in early postmenopausal women with normal or low BMD. Introduction : Bazedoxifene is a novel selective estrogen receptor modulator that has increased BMD and bone strength in experimental models, without stimulating breast or uterus. This 24‐mo, randomized, double‐blind study assessed the efficacy and safety of three doses of bazedoxifene compared with placebo and raloxifene in the prevention of postmenopausal osteoporosis. Materials and Methods : Healthy postmenopausal women with a BMD T‐score at the lumbar spine or femoral neck between –1.0 and ?2.5 or clinical risk factors for osteoporosis were randomly assigned to one of five groups: bazedoxifene 10, 20, or 40 mg/d, placebo, or raloxifene 60 mg/d. All women received elemental calcium. Efficacy outcomes included changes from baseline through 24 mo in BMD of the lumbar spine, hip, femoral neck, and femoral trochanter and biomarkers of bone metabolism. Results : The intent‐to‐treat population included 1434 women (mean age, 58 yr; mean time from last menstrual period, 11 yr). All doses of bazedoxifene and raloxifene prevented bone loss, whereas in the placebo group, there was significant loss of BMD at all skeletal sites. Mean differences in percent change in lumbar spine BMD from baseline to 24 mo relative to placebo were 1.08 ± 0.28%, 1.41 ± 0.28%, 1.49 ± 0.28%, and 1.49 ± 0.28% for 10, 20, and 40 mg bazedoxifene and 60 mg raloxifene, respectively (p < 0.001 for all comparisons). Comparable BMD responses were observed at other body sites. Significant and comparable decreases in serum osteocalcin and C‐telopeptide levels from baseline and relative to placebo with active treatment were observed as early as 3 mo and were sustained through study conclusion (p < 0.001). Overall incidences of adverse events, serious adverse events, and discontinuations caused by adverse events were similar between groups. The most common adverse events included headache, infection, arthralgia, pain, hot flush, and back pain. Conclusions : Treatment with bazedoxifene prevented bone loss and reduced bone turnover equally as well as raloxifene and was generally well tolerated in postmenopausal women with normal/low BMD.     

Effects of Odanacatib on the Radius and Tibia of Postmenopausal Women: Improvements in Bone Geometry,Microarchitecture, and Estimated Bone Strength

The cathepsin K inhibitor odanacatib (ODN), currently in phase 3 development for postmenopausal osteoporosis, has a novel mechanism of action that reduces bone resorption while maintaining bone formation. In phase 2 studies, odanacatib increased areal bone mineral density (aBMD) at the lumbar spine and total hip progressively over 5 years. To determine the effects of ODN on cortical and trabecular bone and estimate changes in bone strength, we conducted a randomized, double‐blind, placebo‐controlled trial, using both quantitative computed tomography (QCT) and high‐resolution peripheral (HR‐p)QCT. In previously published results, odanacatib was superior to placebo with respect to increases in trabecular volumetric BMD (vBMD) and estimated compressive strength at the spine, and integral and trabecular vBMD and estimated strength at the hip. Here, we report the results of HR‐pQCT assessment. A total of 214 postmenopausal women (mean age 64.0 ± 6.8 years and baseline lumbar spine T‐score –1.81 ± 0.83) were randomized to oral ODN 50 mg or placebo, weekly for 2 years. With ODN, significant increases from baseline in total vBMD occurred at the distal radius and tibia. Treatment differences from placebo were also significant (3.84% and 2.63% for radius and tibia, respectively). At both sites, significant differences from placebo were also found in trabecular vBMD, cortical vBMD, cortical thickness, cortical area, and strength (failure load) estimated using finite element analysis of HR‐pQCT scans (treatment differences at radius and tibia = 2.64% and 2.66%). At the distal radius, odanacatib significantly improved trabecular thickness and bone volume/total volume (BV/TV) versus placebo. At a more proximal radial site, odanacatib attenuated the increase in cortical porosity found with placebo (treatment difference = –7.7%, p = 0.066). At the distal tibia, odanacatib significantly improved trabecular number, separation, and BV/TV versus placebo. Safety and tolerability were similar between treatment groups. In conclusion, odanacatib increased cortical and trabecular density, cortical thickness, aspects of trabecular microarchitecture, and estimated strength at the distal radius and distal tibia compared with placebo. © 2014 American Society for Bone and Mineral Research     

Effect of the cathepsin K inhibitor odanacatib administered once weekly on bone mineral density in Japanese patients with osteoporosis—a double-blind, randomized, dose-finding study

Summary

The efficacy and safety of oral placebo or odanacatib 10, 25, or 50 mg once weekly for 52 weeks were evaluated in a double-blind, randomized, multi-center study in Japanese female and male patients with osteoporosis.

Introduction

Odanacatib is a selective and reversible cathepsin K inhibitor that decreases bone resorption and increases bone mineral density (BMD).

Methods

The primary efficacy endpoint was percent change from baseline to week 52 in lumbar spine BMD. Secondary endpoints included percent change in total hip, femoral neck, and trochanter BMD and in bone biomarkers after treatment for 52 weeks.

Results

In this study, 286 patients [94 % female, mean age (SD) 68.2 (7.1) years] were included in the analysis. The least-squares mean percent changes from baseline to week 52 in the groups receiving placebo, 10, 25 and 50 mg of odanacatib for lumbar spine (L1～L4) BMD were 0.5, 4.1, 5.7, and 5.9 % and for total hip BMD were ?0.4, 1.3, 1.8, and 2.7 %, respectively. The changes in femoral neck and trochanter BMD were similar to those at the total hip. Bone turnover markers were reduced in a dose-dependent manner. However, the effects of odanacatib on bone formation markers were less compared with the effects on bone resorption markers. Tolerability and safety profiles were similar among all treatment groups with no dose-related trends in any adverse events.

Conclusions

Weekly odanacatib treatment for 52 weeks increased BMD at the lumbar spine and at all hip sites in a dose-dependent manner and was well tolerated in Japanese patients with osteoporosis.     

Comparison of the Effect of Denosumab and Alendronate on BMD and Biochemical Markers of Bone Turnover in Postmenopausal Women With Low Bone Mass: A Randomized,Blinded, Phase 3 Trial

Denosumab is a fully human monoclonal antibody that inhibits bone resorption by neutralizing RANKL, a key mediator of osteoclast formation, function, and survival. This phase 3, multicenter, double‐blind study compared the efficacy and safety of denosumab with alendronate in postmenopausal women with low bone mass. One thousand one hundred eighty‐nine postmenopausal women with a T‐score ≤ ?2.0 at the lumbar spine or total hip were randomized 1:1 to receive subcutaneous denosumab injections (60 mg every 6 mo [Q6M]) plus oral placebo weekly (n = 594) or oral alendronate weekly (70 mg) plus subcutaneous placebo injections Q6M (n = 595). Changes in BMD were assessed at the total hip, femoral neck, trochanter, lumbar spine, and one‐third radius at 6 and 12 mo and in bone turnover markers at months 1, 3, 6, 9, and 12. Safety was evaluated by monitoring adverse events and laboratory values. At the total hip, denosumab significantly increased BMD compared with alendronate at month 12 (3.5% versus 2.6%; p < 0.0001). Furthermore, significantly greater increases in BMD were observed with denosumab treatment at all measured skeletal sites (12‐mo treatment difference: 0.6%, femoral neck; 1.0%, trochanter; 1.1%, lumbar spine; 0.6%, one‐third radius; p ≤ 0.0002 all sites). Denosumab treatment led to significantly greater reduction of bone turnover markers compared with alendronate therapy. Adverse events and laboratory values were similar for denosumab‐ and alendronate‐treated subjects. Denosumab showed significantly larger gains in BMD and greater reduction in bone turnover markers compared with alendronate. The overall safety profile was similar for both treatments.     

Two-year treatment with denosumab (AMG 162) in a randomized phase 2 study of postmenopausal women with low BMD.

Denosumab is a monoclonal antibody to RANKL. In this randomized, placebo-controlled study of 412 postmenopausal women with low BMD, subcutaneous denosumab given every 3 or 6 mo was well tolerated, increased BMD, and decreased bone resorption markers for up to 24 mo. Continued study of denosumab is warranted in the treatment of low BMD in postmenopausal women. INTRODUCTION: Denosumab is a fully human monoclonal antibody that inhibits RANKL, a key mediator of osteoclastogenesis and bone remodeling. This prespecified exploratory analysis evaluated the efficacy and safety of denosumab through 24 mo in the treatment of postmenopausal women with low BMD. MATERIALS AND METHODS: Four hundred twelve postmenopausal women with lumbar spine BMD T-scores of -1.8 to -4.0 or femoral neck/total hip T-scores of -1.8 to -3.5 were randomly assigned to receive double-blind, subcutaneous injections of placebo; denosumab 6, 14, or 30 mg every 3 mo; denosumab 14, 60, 100, or 210 mg every 6 mo; or open-label oral alendronate 70 mg once weekly. Outcome measures included BMD at the lumbar spine, total hip, distal one-third radius, and total body; bone turnover markers; and safety. RESULTS: Denosumab increased BMD at all measured skeletal sites and decreased concentrations of bone turnover markers compared with placebo at 24 mo. At the lumbar spine, BMD increases with denosumab ranged from 4.13% to 8.89%. BMD changes with denosumab 30 mg every 3 mo and > or =60 mg every 6 mo were similar to, or in some cases greater than, with alendronate. The incidence of adverse events was similar in the placebo, denosumab, and alendronate treatment groups. Exposure-adjusted adverse events over 2 yr of treatment were similar to those reported during the first year of treatment. CONCLUSIONS: In these postmenopausal women with low BMD, treatment with denosumab for 2 yr was associated with sustained increases in BMD and reductions in bone resorption markers compared with placebo.     

A Randomized,Double‐Blind Phase 2 Clinical Trial of Blosozumab,a Sclerostin Antibody,in Postmenopausal Women with Low Bone Mineral Density

Sclerostin, a SOST protein secreted by osteocytes, negatively regulates formation of mineralized bone matrix and bone mass. We report the results of a randomized, double‐blind, placebo‐controlled multicenter phase 2 clinical trial of blosozumab, a humanized monoclonal antibody targeted against sclerostin, in postmenopausal women with low bone mineral density (BMD). Postmenopausal women with a lumbar spine T‐score –2.0 to –3.5, inclusive, were randomized to subcutaneous blosozumab 180 mg every 4 weeks (Q4W), 180 mg every 2 weeks (Q2W), 270 mg Q2W, or matching placebo for 1 year, with calcium and vitamin D. Serial measurements of spine and hip BMD and biochemical markers of bone turnover were performed. Overall, 120 women were enrolled in the study (mean age 65.8 years, mean lumbar spine T‐score –2.8). Blosozumab treatment resulted in statistically significant dose‐related increases in spine, femoral neck, and total hip BMD as compared with placebo. In the highest dose group, BMD increases from baseline reached 17.7% at the spine, and 6.2% at the total hip. Biochemical markers of bone formation increased rapidly during blosozumab treatment, and trended toward pretreatment levels by study end. However, bone specific alkaline phosphatase remained higher than placebo at study end in the highest‐dose group. CTx, a biochemical marker of bone resorption, decreased early in blosozumab treatment to a concentration less than that of the placebo group by 2 weeks, and remained reduced throughout blosozumab treatment. Mild injection site reactions were reported more frequently with blosozumab than placebo. In conclusion, treatment of postmenopausal women with an antibody targeted against sclerostin resulted in substantial increases in spine and hip BMD. These results support further study of blosozumab as a potential anabolic therapy for osteoporosis. © 2014 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research (ASBMR)     

Odanacatib Treatment Affects Trabecular and Cortical Bone in the Femur of Postmenopausal Women: Results of a Two‐Year Placebo‐Controlled Trial

Odanacatib, a selective cathepsin K inhibitor, increases areal bone mineral density (aBMD) at the spine and hip of postmenopausal women. To gain additional insight into the effects on trabecular and cortical bone, we analyzed quantitative computed tomography (QCT) data of postmenopausal women treated with odanacatib using Medical Image Analysis Framework (MIAF; Institute of Medical Physics, University of Erlangen, Erlangen, Germany). This international, randomized, double‐blind, placebo‐controlled, 2‐year, phase 3 trial enrolled 214 postmenopausal women (mean age 64 years) with low aBMD. Subjects were randomized to odanacatib 50 mg weekly (ODN) or placebo (PBO); all participants received calcium and vitamin D. Hip QCT scans at 24 months were available for 158 women (ODN: n = 78 women; PBO: n = 80 women). There were consistent and significant differential treatment effects (ODN‐PBO) for total hip integral (5.4%), trabecular volumetric BMD (vBMD) (12.2%), and cortical vBMD (2.5%) at 24 months. There was no significant differential treatment effect on integral bone volume. Results for bone mineral content (BMC) closely matched those for vBMD for integral and trabecular compartments. However, with small but mostly significant differential increases in cortical volume (1.0% to 1.3%) and thickness (1.4% to 1.9%), the percentage cortical BMC increases were numerically larger than those of vBMD. With a total hip BMC differential treatment effect (ODN‐PBO) of nearly 1000 mg, the proportions of BMC attributed to cortical gain were 45%, 44%, 52%, and 40% for the total, neck, trochanter, and intertrochanter subregions, respectively. In postmenopausal women treated for 2 years, odanacatib improved integral, trabecular, and cortical vBMD and BMC at all femur regions relative to placebo when assessed by MIAF. Cortical volume and thickness increased significantly in all regions except the femoral neck. The increase in cortical volume and BMC paralleled the increase in cortical vBMD, demonstrating a consistent effect of ODN on cortical bone. Approximately one‐half of the absolute BMC gain occurred in cortical bone. © 2014 American Society for Bone and Mineral Research.     

Oral daily ibandronate prevents bone loss in early postmenopausal women without osteoporosis.

Oral daily ibandronate was investigated for the prevention of bone loss in postmenopausal women without osteoporosis (n = 653). BMD at the lumbar spine and hip were significantly increased (3.1% and 1.8%, respectively; p < or = 0.0001 versus placebo) with 2.5 mg ibandronate after 24 months. Oral ibandronate is a promising option for the prevention of postmenopausal bone loss. INTRODUCTION: Further strategies to manage patients most at risk from developing postmenopausal osteoporosis are required. The objectives of this multicenter, double-blind, randomized, placebo-controlled study were to examine the efficacy, tolerability, and optimal dose of oral daily ibandronate in the prevention of bone loss in postmenopausal women. MATERIALS AND METHODS: In total, 653 women (mean bone mineral density [BMD] T-score > -2.5 at the lumbar spine), who had been postmenopausal for at least 1 year, were allocated to one of four strata based on time since menopause and baseline lumbar spine BMD. Women were randomized to receive calcium (500 mg daily) plus either placebo (n = 162) or ibandronate 0.5 mg (n = 162), 1 mg (n = 166), or 2.5 mg (n = 163) as once-daily oral treatment for 2 years. The primary endpoint was the mean percent change in lumbar spine BMD with ibandronate versus placebo. RESULTS AND CONCLUSIONS: After 2 years, oral daily ibandronate produced a dose-related and sustained maintenance or increase in BMD at the lumbar spine and hip (total hip, femoral neck, trochanter), together with a dose-related reduction in the rate of bone turnover. The greatest nominal increases in spinal and hip BMD were observed with the 2.5-mg dose, which produced statistically significant BMD gains compared with placebo at 6 months and all subsequent time-points at the spine and hip (3.1% and 1.8% increase in lumbar spine and total hip BMD, respectively, versus placebo; p < or = 0.0001 after 24 months). Oral daily ibandronate was well tolerated with an incidence of upper gastrointestinal adverse events similar to placebo. No safety concerns were identified. In summary, oral daily ibandronate 2.5 mg decreases bone turnover, preserves or increases BMD in the spine and proximal femur, and is well tolerated. Oral ibandronate provides a promising option for the prevention of bone loss in postmenopausal women.     

Odanacatib in the treatment of postmenopausal women with low bone mineral density: Five years of continued therapy in a phase 2 study

Odanacatib (ODN) is a selective inhibitor of the collagenase cathepsin K that is highly expressed by osteoclasts. In this 2‐year, phase 2, dose‐ranging trial, postmenopausal women with bone mineral density (BMD) T‐scores ?2.0 to ?3.5 at spine or hip were randomized to weekly placebo or ODN 3, 10, 25, or 50 mg plus vitamin D₃ and calcium. Prespecified trial‐extensions continued through 5 years. In year 3, all women were re‐randomized to ODN 50 mg or placebo. For years 4 and 5, women who received placebo or ODN 3 mg in years 1 and 2 and placebo in year 3 received ODN 50 mg; others continued year 3 treatments. Endpoints included lumbar spine (primary), hip, 1/3 radius, and total body BMD; markers of bone metabolism; and safety. Women in the year 4 to 5 extension receiving placebo (n = 41) or ODN 50 mg (n = 100) had similar baseline characteristics. For women who received ODN (10–50 mg) for 5 years, spine and hip BMD increased over time. With ODN 50 mg continually for 5 years (n = 13), mean lumbar spine BMD percent change from baseline (95% confidence interval [CI]) was 11.9% (7.2% to 16.5%) versus ?0.4% (?3.1% to 2.3%) for women who were switched from ODN 50 mg to placebo after 2 years (n = 14). In pooled results of women receiving continuous ODN (10–50 mg, n = 26–29), year 5 geometric mean percent changes from baseline in bone resorption markers cross‐linked N‐telopeptide of type I collagen (NTX)/creatinine and cross‐linked C‐telopeptide (CTX) were approximately ?55%, but near baseline for bone formation markers bone‐specific alkaline phosphatase (BSAP) and amino‐terminal propeptide of type I procollagen (P1NP). In women switched from ODN 10 to 50 mg to placebo after 2 years (n = 25), bone turnover markers were near baseline. In summary, women receiving combinations of ODN (10–50 mg) for 5 years had gains in spine and hip BMD and showed larger reductions in bone resorption than bone formation markers. Discontinuation of ODN resulted in reversal of treatment effects. Treatment with ODN for up to 5 years was generally well‐tolerated. © 2012 American Society for Bone and Mineral Research.     

Safety and efficacy of the cathepsin K inhibitor ONO‐5334 in postmenopausal osteoporosis: The OCEAN study

Osteoporosis occurs when there is an imbalance between resorption and formation of bone, with resorption predominating. Inhibitors of cathepsin K may rebalance this condition. This is the first efficacy study of a new cathepsin K inhibitor, ONO‐5334. The objective of the study was to investigate the efficacy and safety of ONO‐5334 in postmenopausal osteoporosis. This was a 12‐month, randomized, double‐blind, placebo‐ and active‐controlled parallel‐group study conducted in 13 centers in 6 European countries. Subjects included 285 postmenopausal women aged 55 to 75 years with osteoporosis. Subjects were randomized into one of five treatment arms: placebo; 50 mg twice daily, 100 mg once daily, or 300 mg once daily of ONO‐5334; or alendronate 70 mg once weekly. Lumbar spine, total hip, and femoral neck BMD values were obtained along with biochemical markers of bone turnover and standard safety assessments. All ONO‐5334 doses and alendronate showed a significant increase in BMD for lumbar spine, total hip (except 100 mg once daily), and femoral neck BMD. There was little or no suppression of ONO‐5334 on bone‐formation markers compared with alendronate, although the suppressive effects on bone‐resorption markers were similar. There were no clinically relevant safety concerns. With a significant increase in BMD, ONO‐5334 also demonstrated a new mode of action as a potential agent for treating osteoporosis. Further clinical studies are warranted to investigate long‐term efficacy as well as safety of ONO‐5334. © 2011 American Society for Bone and Mineral Research.     

The Effect of the Cathepsin K Inhibitor ONO‐5334 on Trabecular and Cortical Bone in Postmenopausal Osteoporosis: The OCEAN Study

ONO‐5334 (Ono Pharmaceutical Co., Ltd., Osaka, Japan) inhibits cathepsin K and has been shown to increase areal bone mineral density (BMD) at the hip and spine in postmenopausal osteoporosis. Quantitative computed tomography (QCT) allows the study of the cortical and trabecular bone separately and provides structural information such as cortical thickness. We investigated the impact of 2 years of cathepsin K inhibition on these different bone compartments with ONO‐5334. The clinical study was a randomized, double‐blind, placebo, and active controlled parallel group study conducted in 13 centers in six European countries. The original study period of 12 months was extended by another 12 months. A total of 147 subjects (age 55–75 years) of the QCT substudy who participated in the extension period were included. Subjects had been randomized into one of five treatment arms: placebo; ONO‐5334 50 mg twice per day (BID); ONO‐5334 100 mg once daily (QD); ONO‐5334 300 mg QD; or alendronate 70 mg once weekly (QW). QCT was obtained to evaluate bone structure at the lumbar spine and proximal femur. After 24 months ONO‐5334 showed statistically significant increases versus placebo for integral, trabecular, and cortical BMD at the spine and the hip (for ONO‐5334 300 mg QD, BMD increases were 10.5%, 7.1%, and 13.4% for integral, cortical, and trabecular BMD at the spine, respectively, and 6.2%, 3.4%, and 14.6% for integral, cortical, and trabecular total femur BMD, respectively). Changes in cortical and trabecular BMD in the spine and hip were similar for alendronate as for ONO‐5334. Integral volume did not demonstrate statistically significant changes under ONO‐5334 treatment, thus there was no evidence of periosteal apposition, neither at the spine nor at the femur. Cortical thickness changes were not statistically significant for ONO‐5334 in the spine and hip, with exception of a 2.1% increase after month 24 in the intertrochanter for ONO‐5334 300 mg QD. Over 2 years ONO‐5334 showed a statistically significant and persistent increase of trabecular and integral BMD at the spine and the hip. Cortical BMD also progressively increased but at a lower rate. Changes in bone size and of periosteal apposition were not observed. © 2014 American Society for Bone and Mineral Research.     

Once‐Weekly Risedronate in Men With Osteoporosis: Results of a 2‐Year,Placebo‐Controlled,Double‐Blind,Multicenter Study

Male osteoporosis is increasingly recognized as a major public health issue. This multinational, 2‐yr, randomized, double‐blind, placebo‐controlled study was conducted to determine the efficacy and safety of 35 mg once‐a‐week risedronate in men with osteoporosis. Patients had to be men ≥30 yr old, with lumbar spine T‐score ≤ ?2.5 and femoral neck T‐score ≤ ?1 SD or lumbar spine T‐score ≤ ?1 and femoral neck T‐score ≤ ?2 SD (based on young normal men). Patients were randomized 2:1 to risedronate 35 mg once a week or placebo for 2 yr; all patients took 1000 mg elemental calcium and 400–500 IU vitamin D daily. Lumbar spine BMD at month 24 using last observation carried forward was the primary endpoint. Other endpoints included lumbar spine BMD at time points other than month 24, proximal femur BMD, bone turnover markers (BTMs), new vertebral fractures, clinical fractures, and adverse event (AE) assessment. There were 284 men enrolled in the study. Treatment with risedronate resulted in a significant increase from baseline to endpoint in lumbar spine BMD compared with placebo (4.5%; 95% CI: 3.5%, 5.6%; p < 0.001). Few new vertebral and nonvertebral fractures were reported, with no differences in fracture rates between the two groups. There was a significant (p < 0.01) reduction from baseline in BTMs for the risedronate group compared with placebo at all time points. No apparent differences in the pattern or distribution of AEs including serious and upper gastrointestinal AEs were observed. Risedronate therapy was well tolerated during this 2‐yr study and was rapidly effective as indicated by significant BTM decreases at month 3 and BMD increases at month 6 (the earliest time points tested). The effects of risedronate treatment on BMD and BTMs in this study were similar to those previously shown to be associated with fracture risk reductions in women with postmenopausal osteoporosis.     

Effects of bazedoxifene on bone mineral density,bone turnover,and safety in postmenopausal japanese women with osteoporosis

This randomized, double‐blind, placebo‐controlled, dose‐response late phase 2 study evaluated the efficacy and safety of bazedoxifene in postmenopausal Japanese women 85 years of age or younger with osteoporosis. Eligible subjects received daily treatment with oral doses of bazedoxifene 20 or 40 mg or placebo for 2 years. Efficacy assessments included bone mineral density (BMD) at the lumbar spine and other skeletal sites, bone turnover marker levels, lipid parameters, and incidence of new fractures. Of 429 randomized subjects, 387 were evaluable for efficacy, and 423 were included in the safety analyses (mean age, 64 years). At 2 years, the mean percent changes from baseline in lumbar spine BMD were significantly greater with bazedoxifene 20 and 40 mg (2.43% and 2.74%, respectively) than with placebo (?0.65%, p < .001 for both). Both bazedoxifene doses significantly improved BMD at the total hip, femoral neck, and greater trochanter compared with placebo (p < .001 for all). Decreases in bone turnover markers were observed with bazedoxifene 20 and 40 mg as early as 12 weeks (p < .05 for all) and were sustained throughout the study. Total and low‐density lipoprotein cholesterol levels were significantly decreased from baseline with both bazedoxifene doses compared with placebo (p < .05 for all). Incidences of new vertebral and nonvertebral fractures were similar among the bazedoxifene and placebo groups. Overall, the incidence of adverse events with bazedoxifene 20 and 40 mg was similar to that with placebo. Bazedoxifene significantly improved BMD, reduced bone turnover, and was well tolerated in postmenopausal Japanese women with osteoporosis. © 2011 American Society for Bone and Mineral Research.     

BMD changes and predictors of increased bone loss in postmenopausal women after a 5‐year course of alendronate

Management of women discontinuing bisphosphonates after 3 to 5 years of treatment is controversial. Little is known about how much bone mineral density (BMD) is lost after discontinuation or whether there are risk factors for greater rates of bone loss post‐discontinuation. We report patterns of change in BMD and prediction models for the changes in BMD in postmenopausal women during a 5‐year treatment‐free period after alendronate (ALN) therapy. We studied 406 women enrolled in the Fracture Intervention Trial (FIT) who had taken ALN for a mean of 5 years and were then enrolled in the placebo arm of the FIT Long‐Term Extension (FLEX) trial for an additional 5 years, describing 5‐year percent changes in total hip, femoral neck, and lumbar spine BMD over the treatment‐free period. Prediction models of 5‐year percent changes in BMD considered all linear combinations of candidate risk factors for bone loss such as BMD at the start of the treatment‐free period, the change in BMD on ALN, age, and fracture history. Serum for three markers of bone turnover was available in 76 women, and these bone turnover markers were included as candidate predictors for these 76 women. Mean 5‐year BMD changes were –3.6% at the total hip, –1.7% at the femoral neck, and 1.3% at the lumbar spine. Five‐year BMD losses of >5% were experienced by 29% of subjects at the total hip, 11% of subjects at the femoral neck, and 1% of subjects at the lumbar spine. Several risk factors such as age and BMI were associated with greater bone loss, but no models based on these risk factors predicted bone loss rates. Although about one‐third of women who discontinued ALN after 5 years experienced >5% bone loss at the total hip, predicting which women will lose at a higher rate was not possible.     

Efficacy and safety of bazedoxifene in postmenopausal Asian women

Summary

This 6-month study examined the efficacy and safety of bazedoxifene 20?mg in postmenopausal Asian women. Bazedoxifene showed statistically significant improvements over placebo in bone mineral density at all skeletal sites evaluated. Bazedoxifene significantly reduced bone turnover and had favorable effects on lipid parameters. Bazedoxifene was safe and well tolerated.

Introduction

This 6-month, randomized, double-blind, placebo-controlled phase 3 study conducted in China, Korea, and Taiwan evaluated the efficacy and safety of bazedoxifene in postmenopausal Asian women.

Methods

Generally, healthy postmenopausal Asian women (N?=?487; mean age, 57.2?years; mean lumbar spine bone mineral density [BMD], ?1.1) were randomized to daily therapy with bazedoxifene 20?mg or placebo; all subjects received daily supplemental calcium carbonate 600?mg. The changes from baseline in BMD at the lumbar spine (primary end point) and at other skeletal sites, bone turnover markers, and lipid parameters were evaluated at 6?months. Safety assessments included adverse event (AE) reporting and physical/gynecologic examination.

Results

At 6?months, women who received bazedoxifene 20?mg had significantly greater BMD compared with those receiving placebo at the lumbar spine (0.41% vs ?0.32%, P?<?0.01), femoral neck (?0.08% vs ?0.69%, P?=?0.014), trochanter (0.50% vs ?0.23%, P?=?0.010), and total hip (?0.03% vs ?0.77%, P?<?0.001), respectively. Bazedoxifene 20?mg was also associated with significant differences from placebo in median percent reductions from baseline in serum C-telopeptide (?21.8%, P?<?0.001) and osteocalcin (?12.9%, P?<?0.001) levels and total (?5.0%, P?<?0.001) and low-density lipoprotein cholesterol (?9.5%, P?<?0.001) levels. The incidence of AEs was not different between subjects treated with bazedoxifene and those who received placebo.

Conclusion

Bazedoxifene was generally safe and effective in preventing bone loss in this short-term study of postmenopausal Asian women.     

Efficacy and safety of a once‐yearly i.v. Infusion of zoledronic acid 5 mg versus a once‐weekly 70‐mg oral alendronate in the treatment of male osteoporosis: A randomized,multicenter, double‐blind,active‐controlled study

Zoledronic acid (ZOL) has shown beneficial effects on bone turnover and bone mineral density (BMD) in postmenopausal osteoporosis. This study compared the efficacy and safety of a once‐yearly i.v. infusion of ZOL with weekly oral alendronate (ALN) in men with osteoporosis. In this multicenter, double‐blind, active‐controlled, parallel‐group study, participants (n = 302) were randomized to receive either once‐yearly ZOL 5 mg i.v. or weekly oral ALN 70 mg for 24 months. Changes in BMD and bone marker levels were assessed. ZOL increased BMD at the lumbar spine, total hip, femoral neck, and trochanter and was not inferior to ALN at 24 months [least squares mean estimates of the percentage increases in lumbar spine BMD of 6.1% and 6.2%; difference approximately 0.13; 95% confidence interval (CI) 1.12–0.85 in the ZOL and ALN groups, respectively]. At month 12, the median change from baseline of markers for bone resorption [serum β‐C‐terminal telopeptide of type I collagen (β‐CTx) and urine N‐terminal telopeptide of type I collagen (NTx)] and formation [serum N‐terminal propeptide of type I collagen (P1NP) and serum bone‐specific alkaline phosphatase (BSAP)] were comparable between ZOL and ALN groups. Most men preferred i.v. ZOL over oral ALN. The incidence of adverse events and serious adverse events was similar in the treatment groups. It is concluded that a once‐yearly i.v. infusion of ZOL 5 mg increased bone density and decreased bone turnover markers similarly to once‐weekly oral ALN 70 mg in men with low bone density. © 2010 American Society for Bone and Mineral Research.     

Efficacy and safety of ibandronate given by intravenous injection once every 3 months

Oral bisphosphonates are established therapeutics for postmenopausal osteoporosis. Alternative, simplified dosing regimens that improve tolerability and promote convenience may be advantageous. Ibandronate is a highly potent, nitrogen-containing bisphosphonate that can be administered as a convenient intravenous (i.v.) injection (over 15-30 s) in schedules featuring extended between-dose intervals. In a recent fracture prevention study, 1 and 0.5 mg i.v. ibandronate injections, given once every 3 months, were shown to dose-dependently increase lumbar spine and hip bone mineral density (BMD) and decrease biochemical markers of bone turnover in women with postmenopausal osteoporosis, but the overall magnitude of efficacy provided by both doses was suboptimal. In the present study (Intermittent Regimen intravenous Ibandronate Study: the IRIS study), the dose-response relationship with intermittent intravenous ibandronate injections was further evaluated in 520 postmenopausal osteoporotic women (aged 55-75 years, time since menopause >or= 5 years, lumbar spine [L1-L4] BMD T score < -2.5). At enrolment, participants were randomized to receive either 2 mg (n = 261) or 1 mg (n = 131) ibandronate or placebo (n = 128) intravenous injections, given once every 3 months. After 1 year, ibandronate therapy produced substantial and dose-dependent increases in lumbar spine and hip BMD, and decreases in biochemical markers of bone turnover, with the 2 mg dose providing significantly greater efficacy than the 1 mg dose. Most notably, lumbar spine BMD increased by 5.0% and 2.8% in the 2 and 1 mg groups, respectively, and decreased by 0.04% in the placebo group. Furthermore, total hip BMD increased by 2.9%, 2.2%, and 0.6%, respectively. Serum and urinary CTX, reflecting bone resorption, were decreased by 62.5% and 61%, respectively, with the 2 mg dose, and by 43.5% and 42%, respectively, with the 1 mg dose. Intravenous ibandronate was well tolerated with a similar incidence of adverse events to placebo. Importantly, no indicators of renal toxicity were reported. In summary, the 2 mg ibandronate regimen provides significantly greater BMD increases and significantly greater suppression of bone resorption markers than the 1 mg dose used in this study and in the previous fracture prevention study. Ongoing studies aim to further establish the efficacy and convenience of intermittent intravenous ibandronate injections in postmenopausal osteoporosis.     

Denosumab Significantly Increases DXA BMD at Both Trabecular and Cortical Sites: Results From the FREEDOM Study

Denosumab is an approved therapy for postmenopausal women with osteoporosis at high or increased risk for fracture. In the FREEDOM study, denosumab reduced fracture risk and increased bone mineral density (BMD). We report the spine and hip dual-energy X-ray absorptiometry (DXA) BMD responses from the overall study of 7808 women and from a substudy of 441 participants in which more extensive spine and hip assessments as well as additional skeletal sites were evaluated. Significant BMD improvements were observed as early as 1 mo at the lumbar spine, total hip, and trochanter (all p < 0.005 vs placebo and baseline). BMD increased progressively at the lumbar spine, total hip, femoral neck, trochanter, 1/3 radius, and total body from baseline to months 12, 24, and 36 (all p < 0.005 vs placebo and baseline). BMD gains above the least significant change of more than 3% at 36 months were observed in 90% of denosumab-treated subjects at the lumbar spine and 74% at the total hip, and gains more than 6% occurred in 77% and 38%, respectively. In conclusion, denosumab treatment resulted in significant, early, and continued BMD increases at both trabecular and cortical sites throughout the skeleton over 36 mo with important gains observed in most subjects.     

Cathepsin K inhibitors prevent bone loss in estrogen‐deficient rabbits

Two cathepsin K inhibitors (CatKIs) were compared with alendronate (ALN) for their effects on bone resorption and formation in ovariectomized (OVX) rabbits. The OVX model was validated by demonstrating significant loss (9.8% to 12.8%) in lumbar vertebral bone mineral density (LV BMD) in rabbits at 13‐weeks after surgery, which was prevented by estrogen or ALN. A potent CatKI, L‐006235 (L‐235), dosed at 10 mg/kg per day for 27 weeks, significantly decreased LV BMD loss (p < .01) versus OVX‐vehicle control. ALN reduced spine cancellous mineralizing surface by 70%, whereas L‐235 had no effect. Similarly, endocortical bone‐formation rate and the number of double‐labeled Haversian canals in the femoral diaphysis were not affected by L‐235. To confirm the sparing effects of CatKI on bone formation, odanacatib (ODN) was dosed in food to achieve steady‐state exposures of 4 or 9 µM/day in OVX rabbits for 27 weeks. ODN at both doses prevented LV BMD loss (p < .05 and p < .001, respectively) versus OVX‐vehicle control to levels comparable with sham or ALN. ODN also dose‐dependently increased BMD at the proximal femur, femoral neck, and trochanter. Similar to L‐235, ODN did not reduce bone formation at any bone sites studied. The positive and highly correlative relationship of peak load to bone mineral content in the central femur and spine suggested that ODN treatment preserved normal biomechanical properties of relevant skeletal sites. Although CatKIs had similar efficacy to ALN in preventing bone loss in adult OVX rabbits, this novel class of antiresorptives differs from ALN by sparing bone formation, potentially via uncoupling bone formation from resorption. © 2011 American Society for Bone and Mineral Research.