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.     

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,a cathepsin‐K inhibitor for osteoporosis: A two‐year study in postmenopausal women with low bone density

Cathepsin K, a cysteine protease expressed in osteoclasts, degrades type 1 collagen. Odanacatib selectively and reversibly inhibited cathepsin K and rapidly decreased bone resorption in preclinical and phase I studies. A 1‐year dose‐finding trial with a 1‐year extension on the same treatment assignment was performed in postmenopausal women with low bone mineral density (BMD) to evaluate the safety and efficacy of weekly doses of placebo or 3, 10, 25, or 50 mg of odanacatib on BMD and biomarkers of skeletal remodeling. Women with BMD T‐scores of ?2.0 or less but not less than ?3.5 at the lumbar spine or femoral sites were randomly assigned to receive placebo or one of four doses of odanacatib; all received vitamin D with calcium supplementation as needed. The primary endpoint was percentage change from baseline lumbar spine BMD. Other endpoints included percentage change in BMD at hip and forearm sites, as well as changes in biomarkers of skeletal remodeling. Twenty‐four months of treatment produced progressive dose‐related increases in BMD. With the 50‐mg dose of odanacatib, lumbar spine and total‐hip BMD increased 5.5% and 3.2%, respectively, whereas BMD at these sites was essentially unchanged with placebo (?0.2% and ?0.9%). Biochemical markers of bone turnover exhibited dose‐related changes. The safety and tolerability of odanacatib generally were similar to those of placebo, with no dose‐related trends in any adverse experiences. In summary, 2 years of weekly odanacatib treatment was generally well‐tolerated and increased lumbar spine and total‐hip BMD in a dose‐related manner in postmenopausal women with low BMD. © 2010 American Society for Bone and Mineral Research     

The Effect of Discontinuing Treatment With Blosozumab: Follow‐up Results of a Phase 2 Randomized Clinical Trial in Postmenopausal Women With Low Bone Mineral Density

Administration of blosozumab, a humanized monoclonal antibody that binds sclerostin, increases bone formation and bone mineral density (BMD) in postmenopausal women with low BMD. To evaluate the effect of discontinuing blosozumab, we studied women enrolled in a 1‐year randomized, placebo‐controlled phase 2 trial for an additional year after they completed treatment. Of the 120 women initially enrolled in the study, 106 women completed treatment and continued into follow‐up; 88 women completed 1 year of follow‐up. At the beginning of follow‐up, groups remained balanced for age, race, and body mass index, but lumbar spine and total hip BMD were increased in prior blosozumab groups, reflecting an anabolic treatment effect. At the end of follow‐up, 1 year after discontinuing treatment, lumbar spine BMD remained significantly greater than placebo in women initially treated with blosozumab 270 mg every 2 weeks (Q2W) and blosozumab 180 mg Q2W (6.9% and 3.6% above baseline, respectively). Total hip BMD also declined after discontinuation of treatment but at 1 year after treatment remained significantly greater than placebo in women initially treated with blosozumab 270 mg Q2W and blosozumab 180 mg Q2W (3.9% and 2.6% above baseline, respectively). During follow‐up, median serum P1NP was not consistently different between the prior blosozumab groups and placebo. A similar pattern was apparent for median serum C‐terminal telopeptide of type 1 collagen (CTx) levels, with more variability. Mean serum total sclerostin concentration increased with blosozumab, indicating target engagement, and declined to baseline after discontinuation. There were no adverse events considered related to prior treatment with blosozumab. Anti‐drug antibodies generally declined in patients who had detectable levels during prior treatment. These findings support the continued study of blosozumab as an anabolic therapy for treatment of osteoporosis. © 2015 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research (ASBMR).     

Regional bone metabolism at the lumbar spine and hip following discontinuation of alendronate and risedronate treatment in postmenopausal women

Summary

The aim of this study was to examine the effects of bisphosphonate discontinuation on bone metabolism at the spine and hip measured using ¹⁸?F-fluoride PET. Bone metabolism at the spine remained stable following discontinuation of alendronate and risedronate at 1?year but increased in the hip in the alendronate group only.

Introduction

Bisphosphonates such as alendronate (ALN) or risedronate (RIS) have persistent effects on spine BMD following discontinuation.

Methods

Positron emission tomography (PET) was used to examine regional bone metabolism in 20 postmenopausal women treated with ALN (n?=?11) or RIS (n?=?9) for a minimum of 3?years at screening (range 3–9?years, mean 5?years for both groups). Subjects underwent a dynamic scan of the lumbar spine and a static scan of both hips at baseline and 6 and 12?months following treatment discontinuation. ¹⁸?F-fluoride plasma clearance (K_i) at the spine was calculated using a three-compartment model. Standardised uptake values (SUV) were calculated for the spine, total hip, femoral neck and femoral shaft. Measurements of BMD and biochemical markers of bone turnover were also performed.

Results

With the exception of a significant decrease in spine BMD in the ALN group, BMD remained stable. Bone turnover markers increased significantly from baseline by 12?months for both study groups. Measurements of K_i and SUV at the spine and femoral neck did not change significantly in either group. SUV at the femoral shaft and total hip increased significantly but in the ALN group only, increasing by 33.8% (p?=?0.028) and 24.0% (p?=?0.013), respectively.

Conclusions

Bone metabolism at the spine remained suppressed following treatment discontinuation. A significant increase in SUV at the femoral shaft and total hip after 12?months was observed but for the ALN group only. This study was small, and further clinical studies are required to fully evaluate the persistence of BP treatment.     

Continuous treatment with odanacatib for up to 8 years in postmenopausal women with low bone mineral density: a phase 2 study

Summary

The efficacy and safety of weekly oral odanacatib (ODN) 50 mg for up to 8 years were assessed in postmenopausal women with low bone mineral density (BMD). Treatment with ODN for up to 8 years resulted in continued or maintained increases in BMD at multiple sites and was well tolerated.

Introduction

ODN is a selective inhibitor of cathepsin K. In a 2-year phase 2b study (3/10/25/50 mg ODN once weekly [QW] or placebo) and extensions (50 mg ODN QW or placebo), ODN treatment for 5 years progressively increased BMD and decreased bone resorption markers in postmenopausal women with low BMD (ClinicalTrials.gov NCT00112437).

Methods

In this prespecified interim analysis at year 8 of an additional 5-year extension (years 6 to 10), patients (n?=?117) received open-label ODN 50 mg QW plus weekly vitamin D₃ (5600 IU) and calcium supplementation as needed. Primary end points were lumbar spine BMD and safety. Patients were grouped by ODN exposure duration.

Results

Mean (95 % confidence interval [CI]) lumbar spine BMD changes from baseline were 4.6 % (2.4, 6.7; 3-year continuous ODN exposure), 12.9 % (8.1, 17.7; 5 years), 12.8 % (10.0, 15.7; 6 years), and 14.8 % (11.0, 18.6; 8 years). Similar patterns of results were observed for BMD of trochanter, femoral neck, and total hip versus baseline. Geometric mean changes from baseline to year 8 for bone resorption markers were approximately ?50 % (uNTx/Cr) and ?45 % (sCTx), respectively (all groups); bone formation markers remained near baseline levels. No osteonecrosis of the jaw, delayed fracture union, or morphea-like skin reactions were reported.

Conclusions

Treatment with ODN for up to 8 years resulted in gains in BMD at multiple sites. Bone resorption markers remained reduced, with no significant change observed in bone formation markers. Treatment with ODN for up to 8 years was well tolerated.

     

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.     

Odanacatib reduces bone turnover and increases bone mass in the lumbar spine of skeletally mature ovariectomized rhesus monkeys

Odanacatib (ODN) is a selective and reversible inhibitor of cathepsin K (CatK) currently being developed as a once‐weekly treatment for osteoporosis. In this study, we evaluated the effects of ODN on bone turnover, bone mineral density (BMD), and bone strength in the lumbar spine of estrogen‐deficient, skeletally mature rhesus monkeys. Ovariectomized (OVX) monkeys were treated in prevention mode for 21 months with either vehicle, ODN 6 mg/kg, or ODN 30 mg/kg (p.o., q.d.) and compared with intact animals. ODN treatment persistently suppressed the bone resorption markers (urinary NTx [75% to 90%] and serum CTx [40% to 55%]) and the serum formation markers (BSAP [30% to 35%] and P1NP [60% to 70%]) versus vehicle‐treated OVX monkeys. Treatment with ODN also led to dose‐dependent increases in serum 1‐CTP and maintained estrogen deficiency–elevated Trap‐5b levels, supporting the distinct mechanism of CatK inhibition in effectively suppressing bone resorption without reducing osteoclast numbers. ODN at both doses fully prevented bone loss in lumbar vertebrae (L₁ to L₄) BMD in OVX animals, maintaining a level comparable to intact animals. ODN dose‐dependently increased L₁ to L₄ BMD by 7% in the 6 mg/kg group (p < 0.05 versus OVX‐vehicle) and 15% in the 30 mg/kg group (p < 0.05 versus OVX‐vehicle) from baseline. Treatment also trended to increase bone strength, associated with a positive and highly significant correlation (R = 0.838) between peak load and bone mineral content of the lumbar spine. Whereas ODN reduced bone turnover parameters in trabecular bone, the number of osteoclasts was either maintained or increased in the ODN‐treated groups compared with the vehicle controls. Taken together, our findings demonstrated that the long‐term treatment with ODN effectively suppressed bone turnover without reducing osteoclast number and maintained normal biomechanical properties of the spine of OVX nonhuman primates. © 2012 American Society for Bone and Mineral Research     

Effect of ONO‐5334 on Bone Mineral Density and Biochemical Markers of Bone Turnover in Postmenopausal Osteoporosis: 2‐Year Results From the OCEAN Study

Cathepsin K inhibitors, such as ONO‐5334, are being developed for the treatment of postmenopausal osteoporosis. However, their relative effects on bone resorption and formation, and how quickly the effects resolve after treatment cessation, are uncertain. The aim of this study was to examine the efficacy and safety of 24‐month treatment with ONO‐5334 and to assess the effect of treatment cessation over 2 months. We studied 197 postmenopausal women with osteoporosis or osteopenia with one fragility fracture. Patients were randomized to ONO‐5334 50 mg twice daily, 100 mg or 300 mg once daily, alendronate 70 mg once weekly (positive control), or placebo for 24 months. After 24 months, all ONO‐5334 doses were associated with increased bone mineral density (BMD) for lumbar spine, total hip, and femoral neck (p < 0.001). ONO‐5334 300 mg significantly suppressed the bone‐resorption markers urinary (u) NTX and serum and uCTX‐I throughout 24 months of treatment and to a similar extent as alendronate; other resorption marker levels remained similar to placebo (fDPD for ONO‐5334 300 mg qd) or were increased (ICTP, TRAP5b, all ONO‐5334 doses). Levels of B‐ALP and PINP were suppressed in all groups (including placebo) for approximately 6 months but then increased for ONO‐5334 to close to baseline levels by 12 to 24 months. On treatment cessation, there were increases above baseline in uCTX‐I, uNTX, and TRAP5b, and decreases in ICTP and fDPD. There were no clinically relevant safety concerns. Cathepsin K inhibition with ONO‐5334 resulted in decreases in most resorption markers over 2 years but did not decrease most bone formation markers. This was associated with an increase in BMD; the effect on biochemical markers was rapidly reversible on treatment cessation. © 2014 American Society for Bone and Mineral Research.     

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     

FRAME Study: The Foundation Effect of Building Bone With 1 Year of Romosozumab Leads to Continued Lower Fracture Risk After Transition to Denosumab

Romosozumab is a bone‐forming agent with a dual effect of increasing bone formation and decreasing bone resorption. In FRActure study in postmenopausal woMen with ostEoporosis (FRAME), postmenopausal women with osteoporosis received romosozumab 210 mg s.c. or placebo once monthly for 12 months, followed by denosumab 60 mg s.c. once every 6 months in both groups for 12 months. One year of romosozumab increased spine and hip BMD by 13% and 7%, respectively, and reduced vertebral and clinical fractures with persistent fracture risk reduction upon transition to denosumab over 24 months. Here, we further characterize the BMD gains with romosozumab by quantifying the percentages of patients who responded at varying magnitudes; report the mean T‐score changes from baseline over the 2‐year study and contrast these results with the long‐term BMD gains seen with denosumab during Fracture REduction Evaluation of Denosumab in Osteoporosis every 6 Months (FREEDOM) and its Extension studies; and assess fracture incidence rates in year 2, when all patients received denosumab. Among 7180 patients (n = 3591 placebo, n = 3589 romosozumab), most romosozumab‐treated patients experienced ≥3% gains in BMD from baseline at month 12 (spine, 96%; hip, 78%) compared with placebo (spine, 22%; hip, 16%). For romosozumab patients, mean absolute T‐score increases at the spine and hip were 0.88 and 0.32, respectively, at 12 months (placebo: 0.03 and 0.01) and 1.11 and 0.45 at 24 months (placebo‐to‐denosumab: 0.38 and 0.17), with the 2‐year gains approximating the effect of 7 years of continuous denosumab administration. Patients receiving romosozumab versus placebo in year 1 had significantly fewer vertebral fractures in year 2 (81% relative reduction; p < 0.001), with fewer fractures consistently observed across other fracture categories. The data support the clinical benefit of rebuilding the skeletal foundation with romosozumab before transitioning to antiresorptive therapy. © 2018 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals, Inc.     

Effects of 24 Months of Treatment With Romosozumab Followed by 12 Months of Denosumab or Placebo in Postmenopausal Women With Low Bone Mineral Density: A Randomized,Double‐Blind,Phase 2, Parallel Group Study

Over 12 months, romosozumab increased bone formation and decreased bone resorption, resulting in increased bone mineral density (BMD) in postmenopausal women with low BMD (NCT00896532). Herein, we report the study extension evaluating 24 months of treatment with romosozumab, discontinuation of romosozumab, alendronate followed by romosozumab, and romosozumab followed by denosumab. Postmenopausal women aged 55 to 85 years with a lumbar spine (LS), total hip (TH), or femoral neck T‐score ≤–2.0 and ≥–3.5 were enrolled and randomly assigned to placebo, one of five romosozumab regimens (70 mg, 140 mg, 210 mg monthly [QM]; 140 mg Q3M; 210 mg Q3M) for 24 months, or open‐label alendronate for 12 months followed by romosozumab 140 mg QM for 12 months. Eligible participants were then rerandomized 1:1 within original treatment groups to placebo or denosumab 60 mg Q6M for an additional 12 months. Percentage change from baseline in BMD and bone turnover markers (BTMs) at months 24 and 36 and safety were evaluated. Of 364 participants initially randomized to romosozumab, placebo, or alendronate, 315 completed 24 months of treatment and 248 completed the extension. Romosozumab markedly increased LS and TH BMD through month 24, with largest gains observed with romosozumab 210 mg QM (LS = 15.1%; TH = 5.4%). Women receiving romosozumab who transitioned to denosumab continued to accrue BMD, whereas BMD returned toward pretreatment levels with placebo. With romosozumab 210 mg QM, bone formation marker P1NP initially increased after treatment initiation and gradually decreased to below baseline by month 12, remaining below baseline through month 24; bone resorption marker β‐CTX rapidly decreased after treatment, remaining below baseline through month 24. Transition to denosumab further decreased both BTMs, whereas after transition to placebo, P1NP returned to baseline and β‐CTX increased above baseline. Adverse events were balanced between treatment groups through month 36. These data suggest that treatment effects of romosozumab are reversible upon discontinuation and further augmented by denosumab. © 2018 The Authors Journal of Bone and Mineral Research published by Wiley Periodicals, Inc.     

The relationship of biochemical markers of bone turnover to bone density changes in postmenopausal women: results from the Postmenopausal Estrogen/Progestin Interventions (PEPI) trial.

We assessed the associations of eight bone turnover markers (BTMs) with baseline and 1-year percentage changes in lumbar spine and hip bone mineral density (BMD) of 293 postmenopausal women undergoing treatment with hormone replacement therapy (HRT) or placebo using squared correlation coefficients (R2). In 239 women assigned to treatment with estrogen alone or with with estrogen plus progestins (active treatment), mean percentage changes for all markers decreased significantly and remained below baseline values through 3 years of study, whereas mean percentage changes for 54 women assigned to the placebo group showed no significant change from baseline in any marker. At baseline, age and body mass index (BMI) together accounted for 16% and 25% of the variance in spine and hip BMD, respectively. The telopeptide resorption marker, cross-linked N-telopeptide of type I collagen (NTX), alone accounted for 12% and 8% of variance, respectively. Another telopeptide, carboxy-terminal telopeptide of type I collagen (Crosslaps), accounted for 8% and 7% of variance, respectively. A bone-specific alkaline phosphatase (BALP-2) accounted for 8% of variance at the spine and 5% at the hip. No other marker accounted for more than 5% of total variance at either site; adding either baseline NTX, Crosslaps, or BAP-2 to regressions containing age and BMI increased R2 values at the spine and hip to about 22% and 28%, respectively. In the placebo group, baseline spine BMD accounted for 4% of the variance in 1-year spine BMD percentage change, whereas baseline values for age and BMI accounted for 1% and 0% of the variance, respectively; none of the three accounted for more than 0% of hip BMD percentage change; Crosslaps and NTX contributed 5% and 4% to the variance in 1-year spine BMD percentage change, but other markers accounted for < 2% of variance at the spine. At the hip, another BALP (BALP-1) accounted for 4% of variance, but no other baseline marker except NTX accounted for more than 1% of variance. In the active treatment group, baseline values for age, BMI, and spine BMD together accounted for 13% of the percentage change in spine BMD and for 4% of the BMD change at the hip. No individual or pair of baseline markers significantly enhanced these R2 values, but addition of 1-year percentage changes in some individual markers did significantly increase it. The largest R2 value was obtained by adding the percentage change in BALP-2, which increased the R2 in spine BMD percentage change to 20% and that at the hip to 8%. Adding baseline and change variables for all eight markers to the regression increased R2 to 28% at the spine and 12% at the hip. Restricting the set of analyses to individuals who suppressed marker activity beyond the precision error for the measurement did not improve R2s for the regressions. When baseline marker values were stratified into quartiles, only NTX and osteocalcin showed significant relationships between quartile and change in spine BMD, and these did not reach significance at the hip. When the 1-year change in markers was stratified into quartiles, significant relationships with percentage change in spine BMD were observed only for BALP phosphatases. We conclude that BTMs are not a surrogate for BMD to identify women with low bone mass and that they offer little useful information for predicting BMD changes for individual untreated or HRT-treated postmenopausal women.     

Effect of prior and ongoing raloxifene therapy on response to PTH and maintenance of BMD after PTH therapy

Summary Women with osteoporosis on raloxifene were randomized to 1-34hPTH + raloxifene or raloxifene alone for one year. In the PTH + raloxifene group, bone turnover increased 125–584%, spine BMD increased 9.6%, hip BMD increased 1.2–3.6% and radius BMD declined 4.3%. During the follow-up year, on continued raloxifene, BMD declined slightly at all sites except the femoral neck. Introduction The influence of prior antiresorptives on response to 1–34PTH and the ability to maintain BMD gains might differ for antiresorptive agents with different potencies. The objectives were to evaluate biochemical and bone density responses to 1–34PTH in patients on prior and ongoing raloxifene and to determine whether raloxifene maintains bone gains. Methods Forty-two postmenopausal women with osteoporosis on raloxifene were randomized to raloxifene alone or 1–34PTH daily for 12 months (continuing raloxifene). Women were then followed for 12 months on raloxifene alone. Bone turnover markers and BMD were measured at baseline and at 3, 6, 12, 18 and 24 months. Results Biochemical indices increased rapidly during PTH treatment with peak increments of 125–584% for the three markers (p < 0.001 vs. baseline). After one year of PTH, mean BMD increases were 9.6% for spine, 2.7% for total hip, 3.6% for trochanter (all p < 0.005) and 1.2% in femoral neck (NS), while BMD declined 4.3% in the radius (p = 0.003). After PTH withdrawal, on continued raloxifene, BMD declined slightly (0.7–2.9% losses; NS) at all sites, except the femoral neck, where BMD increased modestly (p = 0.04). At 24 months, spine and femoral neck BMD remained significantly higher than baseline, while radius BMD remained significantly lower (all p < 0.04). Conclusion Substantial gains in BMD of the spine and hip, but not the radius, are seen with one year of PTH treatment in patients on prior raloxifene. After PTH is discontinued, raloxifene partially maintains PTH-induced BMD gains in the spine and hip.     

Intramuscular Neridronate in Postmenopausal Women with Low Bone Mineral Density

Compliance to osteoporosis treatment with oral bisphosphonates is very poor. Intermittent intravenous bisphosphonate is a useful alternative, but this route is not readily available. Neridronate, a nitrogen-containing bisphosphonate that can be given intramuscularly (IM), was tested in a phase 2 clinical trial in 188 postmenopausal osteoporotic women randomized to IM treatment with 25 mg neridronate every 2 weeks, neridronate 12.5 or 25 mg every 4 weeks, or placebo. All patients received calcium and vitamin D supplements. The patients were treated over 12 months with 2-year posttreatment follow-up. After 12-month treatment, all three doses were associated with significant bone mineral density (BMD) increases at both the total hip and spine. A significant dose–response relationship over the three doses was observed for the BMD changes at the total hip but not at the spine. Bone alkaline phosphatase decreased significantly by 40–55% in neridronate-treated patients, with an insignificant dose–response relationship. Serum type I collagen C-telopeptide decreased by 58–79%, with a significant dose–response relationship (P < 0.05). Two years after treatment discontinuation, BMD declined by 1–2% in each dose group, with values still significantly higher than baseline at both the spine and the total hip. Bone turnover markers progressively increased after treatment discontinuation, and on the second year of follow-up the values were significantly higher than pretreatment baseline. The results of this study indicate that IM neridronate might be of value for patients intolerant to oral bisphosphonates and unwilling or unable to undergo intravenous infusion of bisphosphonates.     

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.     

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.     

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.     

Assessment of incident spine and hip fractures in women and men using finite element analysis of CT scans

Finite element analysis of computed tomography (CT) scans provides noninvasive estimates of bone strength at the spine and hip. To further validate such estimates clinically, we performed a 5‐year case‐control study of 1110 women and men over age 65 years from the AGES‐Reykjavik cohort (case = incident spine or hip fracture; control = no incident spine or hip fracture). From the baseline CT scans, we measured femoral and vertebral strength, as well as bone mineral density (BMD) at the hip (areal BMD only) and lumbar spine (trabecular volumetric BMD only). We found that for incident radiographically confirmed spine fractures (n = 167), the age‐adjusted odds ratio for vertebral strength was significant for women (2.8, 95% confidence interval [CI] 1.8 to 4.3) and men (2.2, 95% CI 1.5 to 3.2) and for men remained significant (p = 0.01) independent of vertebral trabecular volumetric BMD. For incident hip fractures (n = 171), the age‐adjusted odds ratio for femoral strength was significant for women (4.2, 95% CI 2.6 to 6.9) and men (3.5, 95% CI 2.3 to 5.3) and remained significant after adjusting for femoral neck areal BMD in women and for total hip areal BMD in both sexes; fracture classification improved for women by combining femoral strength with femoral neck areal BMD (p = 0.002). For both sexes, the probabilities of spine and hip fractures were similarly high at the BMD‐based interventional thresholds for osteoporosis and at corresponding preestablished thresholds for “fragile bone strength” (spine: women ≤ 4500 N, men ≤ 6500 N; hip: women ≤ 3000 N, men ≤ 3500 N). Because it is well established that individuals over age 65 years who have osteoporosis at the hip or spine by BMD criteria should be considered at high risk of fracture, these results indicate that individuals who have fragile bone strength at the hip or spine should also be considered at high risk of fracture. © 2014 American Society for Bone and Mineral Research.     

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.