Early Effects of Abaloparatide on Bone Formation and Resorption Indices in Postmenopausal Women With Osteoporosis.

Anabolic osteoporosis drugs improve bone mineral density by increasing bone formation. The objective of this study was to evaluate the early effects of abaloparatide on indices of bone formation and to assess the effect of abaloparatide on modeling-based formation (MBF), remodeling-based formation (RBF), and overflow MBF (oMBF) in transiliac bone biopsies. In this open-label, single-arm study, 23 postmenopausal women with osteoporosis were treated with 80 µg abaloparatide daily. Subjects received double fluorochrome labels before treatment and before biopsy collection at 3 months. Change in dynamic histomorphometry indices in four bone envelopes were assessed. Median mineralizing surface per unit of bone surface (MS/BS) increased to 24.7%, 48.7%, 21.4%, and 16.3% of total surface after 3 months of abaloparatide treatment, representing 5.5-, 5.2-, 2.8-, and 12.9-fold changes, on cancellous, endocortical, intracortical, and periosteal surfaces (p < .001 versus baseline for all). Mineral apposition rate (MAR) was significantly increased only on intracortical surfaces. Bone formation rate (BFR/BS) was significantly increased on all four bone envelopes. Significant increases versus baseline were observed in MBF on cancellous, endocortical, and periosteal surfaces, for oMBF on cancellous and endocortical surfaces, and for RBF on cancellous, endocortical, and intracortical surfaces. Overall, modeling-based formation (MBF + oMBF) accounted for 37% and 23% of the increase in bone-forming surface on the endocortical and cancellous surfaces, respectively. Changes from baseline in serum biomarkers of bone turnover at either month 1 or month 3 were generally good surrogates for changes in histomorphometric endpoints. In conclusion, treatment with abaloparatide for 3 months stimulated bone formation on cancellous, endocortical, intracortical, and periosteal envelopes in transiliac bone biopsies obtained from postmenopausal women with osteoporosis. These increases reflected stimulation of both remodeling- and modeling-based bone formation, further elucidating the mechanisms by which abaloparatide improves bone mass and lowers fracture risk. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Response rates for hip, femoral neck, and lumbar spine bone mineral density in patients treated with abaloparatide followed by alendronate: Results from phase 3 ACTIVExtend.

Abaloparatide is a selective activator of the parathyroid hormone type 1 receptor signaling pathway that favors the stimulation of bone formation. Here, we report a prospective, exploratory analysis of bone mineral density (BMD) response rates comparing sequential abaloparatide/alendronate vs placebo/alendronate across the ACTIVE and ACTIVExtend studies. BMD was measured at the lumbar spine, total hip, and femoral neck from the beginning of ACTIVE to the end of ACTIVExtend (18 months of abaloparatide or placebo followed by about 1 month for re-consent, followed by 24 months of alendronate treatment for a total of 43 months). Responders were defined as those patients who had improvements in BMD at 3 anatomic sites-the lumbar spine, total hip, and femoral neck. Three response thresholds, >0%, >3%, and >6%, were evaluated. Five hundred fifty-eight patients in the abaloparatide/alendronate group and 581 patients in the placebo/alendronate group from ACTIVExtend were included in the analysis. At Month 43, a significantly greater proportion of those in the abaloparatide/alendronate group compared with the placebo/alendronate group responded with BMD changes from ACTIVE baseline of >0%, >3%, and >6% at all 3 anatomic sites (p < 0.001 for each comparison). At the>3% threshold, 60.7% (307/506) vs 24.0% (121/505) of patients experienced BMD increases at all 3 sites in the abaloparatide/alendronate vs placebo/alendronate groups, respectively (p < 0.001). A significantly greater proportion of the abaloparatide/alendronate group experienced BMD increases of>0%, >3%, and >6% at each individual anatomic site compared with the placebo/alendronate group at 43 months (p < 0.001). Additionally, at each visit in ACTIVExtend, there was a significantly greater proportion of patients in the abaloparatide/alendronate group above the 3% threshold at each anatomic site compared with the placebo/alendronate group. Results are consistent with the significant BMD response with abaloparatide vs placebo observed in ACTIVE and with the continued fracture risk reduction with sequential abaloparatide/alendronate compared with placebo/alendronate treatment observed in ACTIVE through ACTIVExtend.

Abaloparatide in patients with mild or moderate renal impairment: results from the ACTIVE phase 3 trial.

Objective: To evaluate, post hoc, the efficacy and safety of abaloparatide by degree of renal impairment.Methods: ACTIVE was a phase 3, 18-month, randomized, double-blind, active-comparator, placebo-controlled study of postmenopausal women with osteoporosis who received subcutaneous abaloparatide 80 µg, placebo, or open-label teriparatide 20 µg daily. Patients with serum creatinine >2.0 mg/dL or 1.5-2.0 mg/dL with an estimated glomerular filtration rate (eGFR) <37 mL/min, calculated by Cockcroft-Gault formula, were excluded.Results: At baseline, 660 patients had eGFR ≥90 mL/min, 1276 had 60 to ˂90 mL/min, and 527 had <60 mL/min. Older age and lower T-scores were associated with greater renal impairment. Among renal-function subgroups, there were no meaningful changes in bone mineral density, fracture risk reduction, or overall incidence of treatment-emergent adverse events in the active-treatment arms. Anemia, nausea, hypercalcemia, and upper-respiratory-tract infection tended to be more frequent with increasing renal impairment. Hypercalcemia measured by albumin-adjusted serum calcium occurred significantly less frequently with abaloparatide than teriparatide in patients with eGFR <60 mL/min (3.6% versus 10.9%; p = .008) and in the overall ACTIVE safety population (3.4% versus 6.4%; p = .006). Computed tomography scans in 376 patients revealed no evidence of increased renal calcification.Conclusion: Increased exposure to abaloparatide and teriparatide in patients with renal impairment led to no meaningful differences in efficacy or safety. These results support the use of abaloparatide without dosage adjustment in patients with renal impairment, provided those with severe renal impairments are monitored for adverse events.

Recommendations for the conduct of clinical trials for drugs to treat or prevent sarcopenia.

PURPOSE: Sarcopenia is an age-related muscle condition which is frequently a precursor of frailty, mobility disability and premature death. It has a high prevalence in older populations and presents a considerable social and economic burden. Potential treatments are under development but, as yet, no guidelines support regulatory studies for new drugs to manage sarcopenia. The objective of this position paper is therefore to suggest a set of potential endpoints and target population definitions to stimulate debate and progress within the medico-scientific and regulatory communities. METHODS: A multidisciplinary expert working group was hosted by the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis, which reviewed and discussed the recent literature from a perspective of clinical experience and guideline development. Relevant parallels were drawn from the development of definition of osteoporosis as a disease and clinical assessment of pharmaceutical treatments for that indication. RESULTS: A case-finding decision tree is briefly reviewed with a discussion of recent prevalence estimations of different relevant threshold values. The selection criteria for patients in regulatory studies are discussed according to the aims of the investigation (sarcopenia prevention or treatment) and the stage of project development. The possible endpoints of such studies are reviewed and a plea is made for the establishment of a core outcome set to be used in all clinical trials of sarcopenia. CONCLUSIONS: The current lack of guidelines for the assessment of new therapeutic treatments for sarcopenia could potentially hinder the delivery of effective medicines to patients at risk.

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.

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.

Quality of life in sarcopenia and frailty.

The reduced muscle mass and impaired muscle performance that define sarcopenia in older individuals are associated with increased risk of physical limitation and a variety of chronic diseases. They may also contribute to clinical frailty. A gradual erosion of quality of life (QoL) has been evidenced in these individuals, although much of this research has been done using generic QoL instruments, particularly the SF-36, which may not be ideal in older populations with significant comorbidities. This review and report of an expert meeting presents the current definitions of these geriatric syndromes (sarcopenia and frailty). It then briefly summarizes QoL concepts and specificities in older populations and examines the relevant domains of QoL and what is known concerning QoL decline with these conditions. It calls for a clearer definition of the construct of disability, argues that a disease-specific QoL instrument for sarcopenia/frailty would be an asset for future research, and discusses whether there are available and validated components that could be used to this end and whether the psychometric properties of these instruments are sufficiently tested. It calls also for an approach using utility weighting to provide some cost estimates and suggests that a time trade-off study could be appropriate.

Selective oestrogen receptor modulators in prevention of breast cancer: an updated meta-analysis of individual participant data.

BACKGROUND: Tamoxifen and raloxifene reduce the risk of breast cancer in women at elevated risk of disease, but the duration of the effect is unknown. We assessed the effectiveness of selective oestrogen receptor modulators (SERMs) on breast cancer incidence. METHODS: We did a meta-analysis with individual participant data from nine prevention trials comparing four selective oestrogen receptor modulators (SERMs; tamoxifen, raloxifene, arzoxifene, and lasofoxifene) with placebo, or in one study with tamoxifen. Our primary endpoint was incidence of all breast cancer (including ductal carcinoma in situ) during a 10 year follow-up period. Analysis was by intention to treat. RESULTS: We analysed data for 83,399 women with 306,617 women-years of follow-up. Median follow-up was 65 months (IQR 54-93). Overall, we noted a 38% reduction (hazard ratio [HR] 0·62, 95% CI 0·56-0·69) in breast cancer incidence, and 42 women would need to be treated to prevent one breast cancer event in the first 10 years of follow-up. The reduction was larger in the first 5 years of follow-up than in years 5-10 (42%, HR 0·58, 0·51-0·66; p<0·0001 vs 25%, 0·75, 0·61-0·93; p=0·007), but we noted no heterogeneity between time periods. Thromboembolic events were significantly increased with all SERMs (odds ratio 1·73, 95% CI 1·47-2·05; p<0·0001). We recorded a significant reduction of 34% in vertebral fractures (0·66, 0·59-0·73), but only a small effect for non-vertebral fractures (0·93, 0·87-0·99). INTERPRETATION: For all SERMs, incidence of invasive oestrogen (ER)-positive breast cancer was reduced both during treatment and for at least 5 years after completion. Similar to other preventive interventions, careful consideration of risks and benefits is needed to identify women who are most likely to benefit from these drugs. FUNDING: Cancer Research UK.

Is diabetes mellitus a heart disease equivalent in women? Results from an international study of postmenopausal women in the Raloxifene Use for the Heart (RUTH) Trial.

BACKGROUND: Several studies have concluded that diabetes mellitus and heart disease carry similar risk for future cardiovascular disease (CVD). Most of these studies were too small to quantify independent risks specific to women. The purpose of this study was to determine whether diabetes mellitus is a coronary heart disease (CHD) risk equivalent for prediction of future CHD and CVD events in women. METHODS AND RESULTS: The Raloxifene Use for the Heart (RUTH) trial was an international, multicenter, double-blind, randomized, placebo-controlled trial of raloxifene and CVD outcomes in 10 101 postmenopausal women selected for high CHD risk. Of these, 3672 had a history of diabetes mellitus without known CHD, and 3265 had a history of CHD without known diabetes mellitus. Cox proportional hazard models were used to compare cardiovascular outcomes in these 2 groups. Mean age at baseline was 67.5 years; median follow-up was 5.6 years. There were 725 deaths, including 450 cardiovascular deaths. In age-adjusted analyses, diabetic women had an increased risk of all-cause mortality compared with women with CHD. Although the overall risk of CHD and CVD was lower in diabetic women compared with women with CHD, the risk of fatal CHD, fatal CVD, and all-cause mortality was similar (hazard ratio [95% confidence interval]: 0.85 [0.65-1.12], 0.99 [0.78-1.25], and 1.18 [0.98-1.42], respectively, after adjusting for age, lifestyle factors, CHD risk factors, statin use, and treatment assignment). CONCLUSIONS: In the RUTH trial, diabetes mellitus was a CHD risk equivalent in women for fatal, but not nonfatal, CHD and CVD.

Femoral strength in osteoporotic women treated with teriparatide or alendronate.

To gain insight into the clinical effect of teriparatide and alendronate on the hip, we performed non-linear finite element analysis of quantitative computed tomography (QCT) scans from 48 women who had participated in a randomized, double-blind clinical trial comparing the effects of 18-month treatment of teriparatide 20 µg/d or alendronate 10mg/d. The QCT scans, obtained at baseline, 6, and 18 months, were analyzed for volumetric bone mineral density (BMD) of trabecular bone, the peripheral bone (defined as all the cortical bone plus any endosteal trabecular bone within 3 mm of the periosteal surface), and the integral bone (both trabecular and peripheral), and for overall femoral strength in response to a simulated sideways fall. At 18 months, we found in the women treated with teriparatide that trabecular volumetric BMD increased versus baseline (+4.6%, p<0.001), peripheral volumetric BMD decreased (-1.1%, p<0.05), integral volumetric BMD (+1.0%, p=0.38) and femoral strength (+5.4%, p=0.06) did not change significantly, but the ratio of strength to integral volumetric BMD ratio increased (+4.0%, p=0.04). An increase in the ratio of strength to integral volumetric BMD indicates that overall femoral strength, compared to baseline, increased more than did integral density. For the women treated with alendronate, there were small (<1.0%) but non-significant changes compared to baseline in all these parameters. The only significant between-treatment difference was in the change in trabecular volumetric BMD (p<0.005); related, we also found that, for a given change in peripheral volumetric BMD, femoral strength increased more for teriparatide than for alendronate (p=0.02). We conclude that, despite different compartmental volumetric BMD responses for these two treatments, we could not detect any overall difference in change in femoral strength between the two treatments, although femoral strength increased more than integral volumetric BMD after treatment with teriparatide.

Long-term raloxifene for postmenopausal osteoporosis.

BACKGROUND: Due to the chronic nature of osteoporosis and the risk of invasive breast cancer, raloxifene 60 mg/day (raloxifene) is intended to be used for long-term treatment (treatment >3 years). SCOPE: We review available information concerning long-term use of raloxifene, present several new analyses, and report new data from patients who underwent iliac crest bone biopsies after 8 years of raloxifene therapy. The most important studies were the Multiple Outcomes of Raloxifene Evaluation (MORE) followed by the Continued Outcomes of Raloxifene Evaluation (CORE). FINDINGS: The primary endpoint in MORE was incidence of vertebral fracture, and the difference between the raloxifene and placebo groups for this endpoint widened during 4 years of therapy, with the relative risk reduction during the fourth year of the study being similar to the relative risk reduction during years 0 to 3 of the study. Continued raloxifene treatment is necessary to preserve bone mineral density (BMD). In MORE, raloxifene lowered markers of bone turnover to a premenopausal reference interval. Biopsies from three patients treated with raloxifene for 8 years showed normal bone and bone cells and double label in all specimens. Invasive breast cancer risk is a clinical consideration in postmenopausal women with osteoporosis, and invasive breast cancer risk reduction was the primary endpoint in CORE. In MORE and CORE, the benefit of raloxifene versus placebo in incidence of invasive breast cancer increased with greater duration of therapy up to 8 years. CONCLUSIONS: The long-term use of raloxifene has been evaluated through changes in fracture risk reduction, BMD, markers of bone turnover, iliac crest bone biopsies, and invasive breast cancer risk reduction.

Recommendations for an update of 2003 European regulatory requirements for registration of drugs to be used in the treatment of RA.

Since 2003, the European Medicines Agency (EMA) document, 'Points to consider on clinical investigation of medicinal products other than NSAIDs (nonsteroidal anti-inflammatory drugs) for the treatment of rheumatoid arthritis' has provided guidance for the clinical development of both biologic and non-biologic disease-modifying antirheumatic drugs (DMARDs). In the last few years, several new products have been developed or are in development for the treatment of RA, which offer significant efficacy with regard to disease control, including prevention of structural damage and disability. Concurrently, novel insights have been gained with respect to the assessment of disease activity, joint damage and disability. New treatment strategies have been established which relate to early therapy, tight control and rapid switching of medication. Accordingly, several new EULAR/ACR recommendations have been or are being developed. Several important additions and changes are needed in the 2003 guidance to incorporate the current scientific knowledge into clinical trial design for the development of future products. Under the auspices of the Group for the Respect of Ethics and Excellence in Science (GREES), a group of experts in the field of RA and clinical trial design met to provide a consensus recommendation for an update to the 2003 EMA guidance document.

Effect of Raloxifene on all-cause mortality.

OBJECTIVE: Raloxifene, a selective estrogen receptor modulator, reduces osteoporosis and invasive breast cancer risk but increases risk for venous thromboembolism and fatal stroke in women with or at high risk for coronary heart disease. To assess the risk/benefit of raloxifene as a preventative treatment, we analyzed treatment effects on overall and cause-specific mortality. METHODS: A pooled analysis of mortality data was performed from large clinical trials of raloxifene (60 mg/day) versus placebo, including the Multiple Outcomes of Raloxifene Evaluation/Continuing Outcomes Relevant to Evista studies (7705 postmenopausal osteoporotic women followed for 4 years and a subset of 4011 participants followed for an additional 4 years; 110 deaths) and the Raloxifene Use for the Heart trial (10,101 postmenopausal women with coronary disease or multiple risk factors for coronary disease followed for 5.6 years; 1149 deaths). Cause of death was assessed by blinded adjudicators. Cox proportional hazards regression models compared mortality by treatment assignment in a pooled analysis of trial data from the Multiple Outcomes of Raloxifene Evaluation/Continuing Outcomes Relevant to Evista and Raloxifene Use for the Heart trials. RESULTS: All-cause mortality was 10% lower among women assigned to raloxifene 60 mg/day versus placebo (relative hazard 0.90; 95% confidence interval, 0.80-1.00; P=.05). Lower overall mortality was primarily due to lower rates of noncardiovascular deaths, especially a lower rate of noncardiovascular, noncancer deaths. CONCLUSIONS: All-cause mortality was 10% lower in pooled analyses among older postmenopausal women receiving raloxifene 60 mg/day compared with placebo, due primarily to a reduction in noncardiovascular, noncancer deaths. The mechanism whereby raloxifene might reduce the risk of noncardiovascular death is unclear.

Teriparatide for acceleration of fracture repair in humans: a prospective, randomized, double-blind study of 102 postmenopausal women with distal radial fractures.

Animal experiments show a dramatic improvement in skeletal repair by teriparatide. We tested the hypothesis that recombinant teriparatide, at the 20 microg dose normally used for osteoporosis treatment or higher, would accelerate fracture repair in humans. Postmenopausal women (45 to 85 years of age) who had sustained a dorsally angulated distal radial fracture in need of closed reduction but no surgery were randomly assigned to 8 weeks of once-daily injections of placebo (n = 34) or teriparatide 20 microg (n = 34) or teriparatide 40 microg (n = 34) within 10 days of fracture. Hypotheses were tested sequentially, beginning with the teriparatide 40 microg versus placebo comparison, using a gatekeeping strategy. The estimated median time from fracture to first radiographic evidence of complete cortical bridging in three of four cortices was 9.1, 7.4, and 8.8 weeks for placebo and teriparatide 20 microg and 40 microg, respectively (overall p = .015). There was no significant difference between the teriparatide 40 microg versus placebo groups (p = .523). In post hoc analyses, there was no significant difference between teriparatide 40 microg versus 20 microg (p = .053); however, the time to healing was shorter in teriparatide 20 microg than placebo (p = .006). The primary hypothesis that teriparatide 40 microg would shorten the time to cortical bridging was not supported. The shortened time to healing for teriparatide 20 microg compared with placebo still may suggest that fracture repair can be accelerated by teriparatide, but this result should be interpreted with caution and warrants further study.

Teriparatide and raloxifene reduce the risk of new adjacent vertebral fractures in postmenopausal women with osteoporosis. Results from two randomized controlled trials.

BACKGROUND: Vertebral fractures increase the risk of new vertebral fractures; however, we are not aware of any study addressing the risk of new vertebral fractures adjacent to existing vertebral fractures. Therefore, we sought to determine the influence of the number and severity of prevalent (preexisting) vertebral fractures on the risk of new adjacent vertebral fractures and to determine whether teriparatide (rhPTH [recombinant human parathyroid hormone] [1-34]) or raloxifene treatment reduces the incidence of adjacent vertebral fractures in postmenopausal women with osteoporosis. METHODS: Data from the Fracture Prevention Trial and the Multiple Outcomes of Raloxifene Evaluation trial were analyzed to determine the incidences of new adjacent and new nonadjacent vertebral fractures in the placebo groups and the effect of treatment with raloxifene and teriparatide on the incidence of new adjacent vertebral fractures as compared with that of new nonadjacent vertebral fractures. RESULTS: Of 1226 untreated postmenopausal women with one or more prevalent vertebral fractures at baseline, 196 (16.0%) had a total of 292 new vertebral fractures during the two-year follow-up period, with 108 (8.8%) of the 1226 women having at least one new fracture adjacent to a prevalent fracture. Of the 292 new vertebral fractures, 136 (47%) were adjacent to a previously existing vertebral fracture. The risk of a new adjacent vertebral fracture was 2.5-fold higher than the risk of a new nonadjacent vertebral fracture (4.03% compared with 1.59%). The incidence of new adjacent vertebral fractures increased with both the number and the severity of prevalent vertebral fractures. Teriparatide reduced the risk of any new, new adjacent, and new nonadjacent vertebral fractures by 72%, 75%, and 70%, respectively, compared with the rates in the placebo group. Similarly, compared with the placebo, raloxifene treatment reduced the risk of any new vertebral fracture, new adjacent vertebral fracture, and new nonadjacent vertebral fracture by 54%, 54%, and 53%, respectively. CONCLUSIONS: In untreated postmenopausal women with osteoporosis, nearly half of the incident vertebral fractures occur adjacent to an existing vertebral fracture. Both teriparatide and raloxifene can significantly reduce the occurrence of new adjacent and nonadjacent vertebral fractures.

Recommendations regarding technical standards for follow-on biologics: comparability, similarity, interchangeability.

BACKGROUND: Policy makers around the world are currently considering the creation of a regulatory pathway for follow-on biologics (FOB), which will have to account for the substantial technical challenges associated with FOB development. These challenges will likely involve more complexity than comparability assessments of process changes made by the same manufacturer. The history of industry-regulator comparability discussions helps explain why the same degree of testing and flexibility now applied to change-control within a manufacturer's own process, at this time, cannot be extrapolated to the observed and possibly unknown differences between two manufacturing processes that are independently developed by different (non-collaborating) parties. OBJECTIVES: This commentary provides recommendations on the technical aspects that should be considered in the creation of an approval pathway for FOB products. CONCLUSIONS: In the authors' view, analytical methodology in its current state cannot alone provide full assurance that the FOB is sufficiently similar to the innovator product. Moreover, the FOB manufacturer will not have access to the extensive knowledge accumulated by the innovator manufacturer from early development through marketing. Thus, extensive clinical evaluation will likely be necessary to provide assurance that the FOB is safe and efficacious. If such testing demonstrates the FOB is safe and efficacious per existing regulatory standards, the product should receive marketing approval as a 'similar' product. Since 'similarity' is a fundamentally different determination than establishing interchangeability between the two products, an interchangeability determination must be based on additional testing and market experience to ensure patient safety. Post-marketing surveillance of the FOB should be conducted to ensure that the approved molecule has similar clinical safety and efficacy as the innovator product, prior to any consideration of interchangeability.

Clinical evaluation of medicinal products for acceleration of fracture healing in patients with osteoporosis.

Pre-clinical studies indicate that pharmacologic agents can augment fracture union. If these pharmacologic approaches could be translated into clinical benefit and offered to patients with osteoporosis or patients with other risks for impaired fracture union (e.g. in subjects with large defects or open fractures with high complication rate), they could provide an important adjunct to the treatment of fractures. However, widely accepted guidelines are important to encourage the conduct of studies to evaluate bioactive substances, drugs, and new agents that may promote fracture union and subsequent return to normal function. A consensus process was initiated to provide recommendations for the clinical evaluation of potential therapies to augment fracture repair in patients with meta- and diaphyseal fractures. Based on the characteristics of fracture healing and fixation, the following study objectives of a clinical study may be appropriate: a) acceleration of fracture union, b) acceleration of return to normal function and c) reduction of fracture healing complications. The intended goal(s) should determine subsequent study methodology. While an acceleration of return to normal function or a reduction of fracture healing complications in and of themselves may be sufficient primary study endpoints for a phase 3 pivotal study, acceleration of fracture union alone is not. Radiographic evaluation may either occur at multiple time points during the healing process with the aim of measuring the time taken to reach a defined status (e.g. cortical bridging of three cortices or disappearance of fracture lines), or could be obtained at a single pre-determined timepoint, were patients are expected to reach a common clinical milestone (i.e. pain free full weight-bearing in weight-bearing fracture cases). Validated Patient Reported Outcomes (PRO's) measures will need to support the return to normal function co-primary endpoints. If reduction of complication rate (e.g. non-union) is the primary objective, the anticipated complications must be defined in the study protocol, along with their possible associations with the specified fracture type and fixation device. The study design should be randomized, parallel, double-blind, and placebo-controlled, and all fracture subjects should receive a standardized method of fracture fixation, defined as Standard of Care.

Effects of teriparatide and alendronate on vertebral strength as assessed by finite element modeling of QCT scans in women with osteoporosis.

UNLABELLED: FE modeling was used to estimate the biomechanical effects of teriparatide and alendronate on lumbar vertebrae. Both treatments enhanced predicted vertebral strength by increasing average density. This effect was more pronounced for teriparatide, which further increased predicted vertebral strength by altering the distribution of density within the vertebra, preferentially increasing the strength of the trabecular compartment. INTRODUCTION: Teriparatide 20 microg/day (TPTD) and alendronate 10 mg/day (ALN) increase areal, measured by DXA, and volumetric, measured by QCT, lumbar spine BMD through opposite effects on bone remodeling. Using finite element (FE) modeling of QCT scans, we sought to compare the vertebral strength characteristics in TPTD- and ALN-treated patients. MATERIALS AND METHODS: A subset of patients (N = 28 TPTD; N = 25 ALN) from the Forteo Alendronate Comparator Trial who had QCT scans of the spine at baseline and postbaseline were analyzed. The QCT scans were analyzed for compressive strength of the L(3) vertebra using FE modeling. In addition, using controlled parameter studies of the FE models, the effects of changes in density, density distribution, and geometry on strength were calculated, a strength:density ratio was determined, and a response to bending was also quantified. RESULTS: Both treatments had positive effects on predicted vertebral strength characteristics. At least 75% of the patients in each treatment group had increased strength of the vertebra at 6 months compared with baseline. Patients in both treatment groups had increased average volumetric density and increased strength in the trabecular bone, but the median percentage increases for these parameters were 5- to 12-fold greater for TPTD. Larger increases in the strength:density ratio were also observed for TPTD, and these were primarily attributed to preferential increases in trabecular strength. CONCLUSIONS: These results provide new insight into the effects of these treatments on estimated biomechanical properties of the vertebra. Both treatments positively affected predicted vertebral strength through their effects on average BMD, but the magnitudes of the effects were quite different. Teriparatide also affected vertebral strength by altering the distribution of density within the vertebra, so that overall, teriparatide had a 5-fold greater percentage increase in the strength:density ratio.