Increase In Bone-specific Alkaline Phosphatase Research Articles

Ker-050 Treatment Reduced Iron Overload and Increased Bone Specific Alkaline Phosphatase in Participants with Lower-Risk MDS Supporting Potential to Restore Balance to the Osteohematopoietic Niche

Background: Iron overload (IO) in myelodysplastic syndromes (MDS) contributes to the deterioration of the osteohematopoietic niche (OHN), where hematopoietic and osteogenic precursors interact to regulate hematopoiesis and bone metabolism. Excess iron exacerbates ineffective hematopoiesis, inflammation, and bone loss via direct effects on resident hematopoietic and osteogenic precursors. Iron chelation therapy (ICT) is associated with improved event-free survival in patients with MDS but does not address the underlying cause of IO and introduces patient burden due to tolerability and cost. KER-050 is an investigational, modified activin receptor type IIA ligand trap designed to inhibit select TGF-β superfamily ligands (activins A, B, GDFs 8, 11) and promote differentiation and maturation of erythroid and megakaryocytic precursors. KER-050 has potential to reduce dependence on red blood cell transfusions and increase iron utilization via erythropoiesis, possibly mitigating IO at its source. As previously reported from an ongoing Phase 2 study (NCT04419649), KER-050 treatment in participants with lower-risk (LR) MDS resulted in rates of modified IWG 2006 Hematological Improvement-Erythroid (HI-E) and transfusion independence (TI) of 51.4% and 42.3%, respectively, with a mean decrease in ferritin (322 ng/mL at Week 24) among HI-E and/or TI responders. KER-050 treatment also demonstrated effects on osteogenic precursors, including prevention of bone loss in a mouse model of MDS and dose-dependent increases in bone specific alkaline phosphatase (BSAP), a marker of bone formation, observed in healthy postmenopausal women. Thus, KER-050 has potential to address the multifaceted pathogenesis of MDS, including IO. Here, we present new data from the ongoing Phase 2 study in MDS, exploring the potential of KER-050 to provide benefit beyond hematologic responses and to ameliorate IO in MDS. Methods: This ongoing Phase 2 study is evaluating KER-050 in participants with LR MDS. Data from exploratory assessments of markers of IO, hematopoiesis, and bone turnover are presented as of a cutoff date of April 3, 2023, for all participants who had received the recommended Part 2 dose (RP2D; 3.75-5 mg/kg q4wks). Results: Baseline ferritin levels in RP2D participants (N=59) were generally elevated, while levels of mean corpuscular hemoglobin and reticulocyte hemoglobin were in the normal range (Table 1). After KER-050 treatment, sustained decreases in serum ferritin were observed among participants with baseline levels ≥1000 ng/mL (Figure 1), likely driven in part by reduced transfusion burden in responders. Concomitant increases observed in soluble transferrin receptor (sTfR; Figure 1) suggest that increased erythropoiesis may also have contributed. Mean decreases in ferritin observed in non-transfused (NT) participants (-228 ng/mL at Week 24, n=7) indicate potential for KER-050 to affect iron homeostasis by mechanisms other than transfusion reduction. In 1 NT participant receiving ICT, the baseline ferritin of 1632 ng/mL decreased to <500 ng/mL over 32 weeks, leading to ICT discontinuation and coinciding with an increase in hemoglobin (Hgb) from 9.2 g/dL at baseline to 11.3 g/dL over the same period. In another NT participant not receiving ICT, ferritin decreased from 1094 ng/mL at baseline to 884 ng/mL and 583 ng/mL at Weeks 24 and 68, respectively, while Hgb gradually increased from 9.94 g/dL at baseline to 10.7 and 12.2 g/dL at Weeks 24 and 68. KER-050 treatment was also associated with increases in BSAP, a new finding in this MDS population that is consistent with prior observations in preclinical and healthy volunteer studies. Despite some heterogeneity, mean increases of 8.47% (n=23) and 10.4% (n=13) were observed at Weeks 24 and 48, respectively; 3 participants with erythroid responses had increases in BSAP of ≥30% at these time points. Summary: Exploratory data indicate potential for KER-050 to drive meaningful decreases in ferritin in participants with LR MDS, particularly among those with IO. While transfusion reduction likely contributes, observations in NT participants highlight the potential for enhancement of erythropoiesis to improve IO, irrespective of transfusions. Observed changes in BSAP suggest that KER-050 is also acting on osteogenic precursors, with the potential to provide functional improvements within the OHN. Updated results will be provided at the presentation.

The Effects of Polyphenols on Bone Metabolism in Postmenopausal Women: Systematic Review and Meta-Analysis of Randomized Control Trials.

Osteoporosis is a condition favored by the postmenopausal decline in estrogen levels and worsened by oxidative stress (OS). Polyphenols are natural compounds abundantly found in fruits and vegetables, and they exert antioxidant and hormonal effects that could be useful in osteoporosis prevention, as suggested by epidemiological studies showing a lower incidence of fractures in individuals consuming polyphenol-rich diets. The aim of our meta-analysis is to evaluate the effects of polyphenols on bone mineral density (BMD, primary endpoint) and bone turnover markers (BTMs, secondary endpoint) in postmenopausal women. Twenty-one randomized control trials (RCTs) were included in our analysis after in-depth search on PubMed, EMBASE, and Scopus databases. We found that supplementation with polyphenols for 3-36 months exerted no statically significant effects on BMD measured at lumbar spine (sMD: 0.21, 95% CI [-0.08 to 0.51], p = 0.16), femoral neck (sMD: 0.16, 95% CI [-0.23 to 0.55], p = 0.42), total hip (sMD: 0.05, 95% CI [-0.14 to 0.24], p = 0.61), and whole body (sMD: -0.12, 95% CI [-0.42 to 0.17], p = 0.41). Subgroup analysis based on treatment duration showed no statistical significance, but a significant effect on lumbar BMD emerged when studies with duration of 24 months or greater were analyzed separately. On the other hand, we found a significantly slight increase in bone-specific alkaline phosphatase (BALP) levels (sMD: 1.27, 95% CI [1.13 to 1.42], p < 0.0001) and a decrease in pyridinoline (PD) levels (sMD: -0.58, 95% CI [-0.77 to -0.39], p < 0.0001). High heterogeneity among studies and unclear risk of bias in one third of the included studies emerged. A subgroup analysis showed similar effects for different duration of treatment and models of dual-energy X-ray absorptiometry (DXA) scanner. More robust evidence is needed before recommending the prescription of polyphenols in clinical practice.

Impact of Physical Rehabilitation on Bone Biomarkers in Non-Metastatic Breast Cancer Women: A Systematic Review and Meta-Analysis.

Rehabilitation might improve bone health in breast cancer (BC) patients, but the effects on bone biomarkers are still debated. Thus, this meta-analysis of randomized controlled trials (RCTs) aims at characterizing the impact of rehabilitation on bone health biomarkers in BC survivors. On 2 May 2022, PubMed, Scopus, Web of Science, Cochrane, and PEDro were systematically searched for RCTs assessing bone biomarker modifications induced by physical exercise in BC survivors. The quality assessment was performed with the Jadad scale and the Cochrane risk-of-bias tool for randomized trials (RoBv.2). Trial registration number: CRD42022329766. Ten studies were included for a total of 873 patients. The meta-analysis showed overall significant mean difference percentage decrease in collagen type 1 cross-linked N-telopeptide (NTX) serum level [ES: -11.65 (-21.13, -2.17), p = 0.02)] and an increase in bone-specific alkaline phosphatase (BSAP) levels [ES: +6.09 (1.56, 10.62). According to the Jadad scale, eight RCTs were considered high-quality studies. Four studies showed a low overall risk of bias, according to RoBv.2. The significant effects of rehabilitation on bone biomarkers suggested a possible implication for a precision medicine approach targeting bone remodeling. Future research might clarify the role of bone biomarkers monitoring in rehabilitation management of cancer treatment induced bone-loss.

Effect of intradialytic exercise on bone profile in hemodialysis patients

BackgroundChronic kidney disease increases the risk of fractures and altered bone and mineral metabolism. Exercise training could be a non-pharmacological therapeutic intervention. The aim of this work is to evaluate the effect of intradialytic exercise training on bone markers in hemodialysis (HD) patients.ResultsForty adult patients on regular HD participated in the study. Twenty of which completed 3 months supervised intradialytic cycling exercise program and 20 served as controls. At baseline, there was no difference between both groups regarding age, sex, physical performance, and laboratory studies performed. After 3 months, the exercise group showed significant improvement in short performance battery test (SPBT) total score (P<0.001) associated with significant decrease in serum parathormone (PTH) (P=0.01) and increase in serum alkaline phosphatase (ALP) and bone specific alkaline phosphatase (BALP) (P<0.05 and P<0.001 respectively). Controls did not show similar change in SPBT or laboratory studies. There was no significant change in serum calcium or phosphorus in both groups. A significant positive correlation was observed between SPBT scores post-exercise and both BALP and ALP levels (r=0.432, P=0.01 and r=0.645, P<0.01 respectively). Also, an inverse relation was observed between SPBT and PTH (r=−0.503, P=0.01).ConclusionIntradialytic cycling exercise program resulted in significant increase in physical performance associated with decrease in serum PTH and increase in BALP and ALP in HD patients. This indicates the positive influence of exercise not only on physical performance in dialysis patients but also on bone metabolism.

Soluble corn fiber increases bone calcium retention in postmenopausal women in a dose-dependent manner: a randomized crossover trial

Background: Dietary soluble corn fiber (SCF) significantly improves calcium absorption in adolescents and the bone strength and architecture in rodent models.Objective: In this study, we aimed to determine the skeletal benefits of SCF in postmenopausal women.Design: We used our novel technology of determining bone calcium retention by following the urinary appearance of 41Ca, a rare long-lived radioisotope, from prelabeled bone to rapidly and sensitively evaluate the effectiveness of SCF in reducing bone loss. A randomized-order, crossover, double-blinded trial was performed in 14 healthy postmenopausal women to compare doses of 0, 10, and 20 g fiber from SCF/d for 50 d.Results: A dose-response effect was shown with 10 and 20 g fiber from SCF/d, whereby bone calcium retention was improved by 4.8% (P < 0.05) and 7% (P < 0.04), respectively. The bone turnover biomarkers N-terminal telopeptide and osteocalcin were not changed by the interventions; however, a significant increase in bone-specific alkaline phosphatase, which is a bone-formation marker, was detected between 0 and 20 g fiber from SCF/d (8%; P = 0.035).Conclusion: Daily SCF consumption significantly increased bone calcium retention in postmenopausal women, which improved the bone calcium balance by an estimated 50 mg/d. This study was registered at clinicaltrials.gov as NCT02416947.

The Clinical Utility of Bone Resorption and Bone Formation Markers in Multiple Myeloma

Introduction: While bone resorption markers such as urinary N-terminal telopeptide (NTx) have long been used in research, serum C-terminal telopeptide (CTx) has become the preferred marker of bone status in multiple myeloma (MM). A full understanding of the clinical utility of CTx, as well as the bone formation markers osteocalcin (OC) and bone-specific alkaline phosphatase (BSAP), in MM is still lacking. In this study, we evaluated levels of CTx, OC, and BSAP in a cohort of MM patients to better understand their roles.Methods: One set of CTx, OC, and BSAP data was obtained by random sampling in patients during a 60-day window at the Weill Cornell Medical College Myeloma Center. Bone marker changes were assessed with respect to type of myeloma therapy, response status, use of anti-resorptive therapy, and presence of osteolytic lesions or fractures. Additionally, we tested the ability of the bone markers to isolate a high fracture risk group, as defined by radiologic evidence of impending fracture. The Wilcoxon-Mann-Whitney test was used to assess clinical variables, and a 2-sided t value of less than 0.05 indicated statistical significance.Results: 50 patients were identified with bone marker data, of which 47 had MM and 3 had MM precursor diseases. The mean age was 64 years, with 25 males and 25 females. All three markers CTx (p=0.001), OC (p=0.004), and BSAP (p<0.001) significantly decreased with myeloma therapy initiation. Only CTx, however, was significantly lower in patients who achieved a partial response or greater, compared to non-responders (p=0.010). Moreover, only CTx decreased significantly in patients using anti-resorptive therapy within one year of bone marker date (p=0.006). Both CTx (p=0.011) and BSAP (p=0.005) were significantly higher in patients with more than 5 osteolytic lesions compared to those without such lesions. Additionally, only CTx predicted which patients were at risk for impending fracture (p<0.001). Of 8 patients in this high-risk group for fractures, 2 developed new pathological fractures within 1 month of the CTx test. CTx values were significantly higher in patients who were taking both proteasome inhibitor (PI) and alkylating agents compared to those only taking PIs (p<0.001). Choice of PI also affected levels of bone markers, with patients receiving bortezomib having significantly higher levels of CTx (p=0.019) than those on carfilzomib. BSAP levels were similarly higher, with a trend toward significance (p=0.064).Discussion: Of the evaluated bone markers, only CTx correlated with response to anti-MM therapy and risk of impending fracture. Additionally, CTx reflects the extent of bone disease. CTx levels decreased with use of anti-resorptive therapy within one year of bone marker date, but not with longer time points. This suggests the clinical benefit of at least annual dosing of anti-resorptive therapy and indicates the dynamic nature of this marker. The high CTx values in the PI plus alkylating group may also suggest that PI alone is more effective in addressing bone disease in such patients. Differences in CTx between individual proteasome inhibitors points to agent-specific effects of PI on bone remodeling, which warrant further investigation. The potential increase in BSAP with bortezomib versus carfilzomib treatment is consistent with recent findings, which show that bortezomib promotes osteoblastic differentiation and bone formation. As opposed to our CTx data, OC and BSAP did not prognosticate disease response or future fractures or correlate with use of anti-resorptive therapy, suggesting limited utility of these bone formation markers in MM.Table 1Bone MarkerCategoryMM Therapy InitiationMM Therapy RespondersART Use Within 1 YearART Use Before 1 YearLytic Lesions Present5+ lytic Lesions PresentRisk of Future FracturePI Plus AlkylatorCTxBone Resorption↓↓↓↓↓NS↑↑↑↑↑↑↑↑OCBone Formation↓↓NSNSNSNSNSNSNSBSAPBone Formation↓↓NSNSNS↑↑↑NS↑Abbreviations: CTx, C-terminal telopeptide; OC, osteocalcin; BSAP, bone-specific alkaline phosphatase; MM, multiple myeloma; ART, anti-resorptive therapy; NS, not significant; PI, proteasome inhibitor. Single arrow represents a change by a factor of less than 2. Double arrows represent a change by a factor of greater than 2. Triple arrows represent a change by a factor of greater than 3. DisclosuresPearse:Celegen: Consultancy. Rossi:Calgene: Speakers Bureau. Mark:Calgene: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Niesvizky:Celgene: Consultancy, Speakers Bureau. Lane:Agnovos Healthcare, LLC: Consultancy; Bone Therapeutics: Membership on an entity's Board of Directors or advisory committees; CollPlant Holdings, Ltd.: Consultancy; D'Fine, Inc.: Consultancy; Gradtys: Membership on an entity's Board of Directors or advisory committees; ISTO Technologies, Inc: Membership on an entity's Board of Directors or advisory committees; Kuros: Membership on an entity's Board of Directors or advisory committees; Royal Consulting & Marketing: Consultancy.

Long-Term Follow-up of patients on Drug Holiday from Bisphosphonates: Real-World Setting

ObjectiveAtypical femoral fractures and osteoporosis of the jaw have been associated with prolonged bisphosphonate therapy for postmenopausal osteoporosis. American Association of Clinical Endocrinologists guidelines suggest a drug holiday after 4 to 5 years of bisphosphonate treatment for moderate-risk patients and 10 years for high-risk patients, but there are minimal data on safe holiday durations. A recent U.S. Food and Drug Administration perspective suggests a treatment duration of 3 to 5 years. Our aim was to describe a group of patients on drug holiday and identify fracture risk. MethodsA retrospective chart review was conducted of 209 patients who started a bisphosphonate drug holiday between 2005 and 2010. Collected data included bone mineral density (BMD), markers of bone turnover, vitamin D status, and clinical and radiographic reports of fractures. ResultsEleven of 209 patients (5.2%) developed a fracture. Their mean age was 69.36 years (±15.58), and the mean lumbar spine and femoral neck T-scores were −2.225 (±1.779) and −2.137 (±0.950), respectively. All patients had a significant increase in bone-specific alkaline phosphatase at 6 months, which was more pronounced in the fracture group (3.0 ± 0.6083 μg/L vs. 1.16 ± 1.9267 μg/L). Over 4 years, there was no significant change in mean lumbar spine BMD for the entire cohort, but there was a statistically significant decline in the femoral neck BMD at year 2 (−0.0084 ± 0.03 gm/cm2). ConclusionThe current practice of initiating BP holidays needs further evaluation, particularly in the real-world setting. Elderly patients and those with very low BMD warrant close follow-up during a drug holiday. A fracture, early significant rise in bone turnover markers, and/or a decline in BMD should warrant resumption of osteoporosis therapy. (Endocr Pract. 2013;19:989-994)

The Effect of Different Amounts of Calcium Intake on Bone Metabolism and Arterial Calcification in Ovariectomized Rats

Low calcium (Ca) intake is the one of risk factors for both bone loss and medial elastocalcinosis in an estrogen deficiency state. To examine the effect of different amounts of Ca intake on the relationship between bone mass alteration and medial elastocalcinosis, 6-wk-old female SD rats were randomized into ovariectomized (OVX) control or OVX treated with vitamin D(3) plus nicotine injection (VDN) groups. The OVX treated with VDN group was then divided into 5 groups depending on the different Ca content in their diet, 0.01%, 0.1%, 0.6%, 1.2%, and 2.4% Ca intakes. After 8 wk of experimentation, the low Ca intake groups of 0.01% and 0.1% showed a low bone mineral density (BMD) and bone properties significantly different from those of the other groups, whereas the high Ca intake groups of 1.2% and 2.4% showed no difference compared with the OVX control. Only in the 0.01% Ca intake group, a significantly higher Ca content in the thoracic artery was found compared with that of the OVX control. Arterial tissues of the 0.01% Ca intake group showed an increase of bone-specific alkaline phosphatase (BAP) activity, a marker of bone mineralization, associated with arterial Ca content. However, the high Ca intake did not affect arterial Ca content nor arterial BAP activity. These results suggested that a low Ca intake during periods of rapid bone loss caused by estrogen deficiency might be one possible cause for the complication of both bone loss and medial elastocalcinosis.

Effect of Epidural Steroid Injection on Bone Mineral Density and Markers of Bone Turnover in Postmenopausal Women

A prospective, observational study. To evaluate the effect of epidural steroid injection (ESI) on bone mineral density (BMD) in postmenopausal women. ESIs are used to treat the pain associated with radiculopathy. Although it is known that exogenous steroid use can disrupt skeletal architecture, it is less clear whether ESIs result in a decrease of BMD. Twenty-eight postmenopausal women experiencing radiculopathy elected L4-L5 ESI treatment. We had a 50% dropout rate due to noncompliance with study requirements. BMD of the hip, femoral neck, and spine along with markers of bone turnover, bone specific-alkaline phosphatase and serum C-telopeptide of collagen I (CTX), was evaluated at baseline preinjection and 3 and 6 months postinjection. There was a significant decline in the hip BMD of 0.018 g/cm (0.028 ± 0.007, P = 0.002) at 6 months compared with baseline. We compared this decline with an age-matched control population that exhibited a decline of 0.003 g/cm(2), significantly less than our study population (P = 0.007). Bone-specific alkaline phosphatase increased significantly by 2.33 U/L from 3 to 6 months (P = 0.012), but the rise of CTX was not significant. A single ESI in postmenopausal women adversely affects BMD of the hip. This is in conjunction with a rise in bone remodeling activity, as evidenced by an increase in bone-specific alkaline phosphatase and CTX. In addition, when compared with an age-matched control population, our study population exhibited a greater decline in BMD. Our findings show that epidural administration of corticosteroids has a deleterious effect on bone, which should be considered when contemplating treatment options for radiculopathy. The resulting decrease in BMD, while slight, suggests that ESIs should be used with caution in those at a risk for fracture.

First‐line treatment with bortezomib rapidly stimulates both osteoblast activity and bone matrix deposition in patients with multiple myeloma, and stimulates osteoblast proliferation and differentiation in vitro

Objectives:The aim of the study was to investigate the effect of bortezomib on osteoblast proliferation and differentiation, as well as on bone matrix deposition for the first time in bisphosphonate-naïve, previously untreated patients with myeloma.Methods:Twenty newly diagnosed patients received four cycles of bortezomib treatment, initially as monotherapy and then combined with a glucocorticoid from cycle two to four. Bone remodeling markers were monitored closely during treatment. Furthermore, the effects of bortezomib and a glucocorticoid on immature and mature osteoblasts were also studied in vitro.Results:Treatment with bortezomib caused a significant increase in bone-specific alkaline phosphatase and pro-collagen type I N-terminal propeptide, a novel bone formation marker. The addition of a glucocorticoid resulted in a transient decrease in collagen deposition. In vitro bortezomib induced osteoblast proliferation and differentiation. Differentiation but not proliferation was inhibited by glucocorticoid treatment.Conclusions:Bortezomib used as first-line treatment significantly increased collagen deposition in patients with multiple myeloma and osteolytic lesions, but the addition of a glucocorticoid to the treatment transiently inhibited the positive effect of bortezomib, suggesting that bortezomib may result in better healing of osteolytic lesions when used without glucocorticoids in patients that have obtained remission with a previous therapy. The potential bone-healing properties of single-agent bortezomib are currently being explored in a clinical study in patients who have undergone high-dose therapy and autologous stem cell transplantation.

The effects of strontium ranelate on biochemical markers of bone turnover and their relationship with bone mineral density

Dear Editors, We would like to comment on the article by Bruyere et al. [1]. In our opinion, the conclusion that short-term changes in biochemical markers of bone formation and their association with BMD changes suggest a bone-forming activity of strontium ranelate (SrR) is flawed, given the several limitations in this post hoc analysis that need to be considered. Biochemical markers of bone remodelling were assessed at baseline, after 3 and 6 months, and every 6 months thereafter over 3 years. However, only 3-month results are presented [1]. Given the lack of data at later time points, it can be argued that a single early measurement could be a spurious finding, and a full description of the changes of these biochemical markers over time would be more conclusive of the effects of SrR on bone remodelling. The authors state that early changes in markers are close to the coefficient of variation of the immunoassays, and in a substantial proportion of subjects, the changes could be within the variability of the method. Indeed, it is not indicated whether the increases in bone-specific alkaline phosphatase (BALP) (9.6%) and C-terminal propeptide of type I procollagen (PICP) (9.9%) were statistically significant compared to baseline after a 3month treatment with SrR. Previous studies have shown that treatment with SrR was associated with statistically significant decreases in the concentrations of total aminoterminal propeptide of type I collagen and C-telopeptide cross-links (S-CTX) from baseline [2–4], a finding that is consistent with a weak anti-remodelling activity of this drug [2]. The hypothetical bone-forming effect of SrR would be better demonstrated by comparing the changes in bone markers induced by this drug, with those observed in the pooled placebo-treated patients of the trials included in the analysis, but these data are missed in the paper. The comparison of the response of PICP between the SrR and the placebo groups would be of special interest A reply to this letter can be found at doi 10.1007/s00198-009-1156-y

ACE-011, a soluble activin receptor type IIA IgG-Fc fusion protein, decreases follicle stimulating hormone and increases bone-specific alkaline phosphatase, a marker of bone formation, in postmenopausal healthy women.

Abstract Abstract #1160 Breast cancer metastasizes to bone in up to 85% of patients with advanced disease. Skeletal-related morbidity such as pathologic fractures, spinal cord compression, or the need for radiotherapy or surgery to the bone will occur in the majority of these patients within 2 years after diagnosis of metastatic disease. Anti-resorptive agents, such as bisphosphonates, are effective agents in inhibiting osteoclast activity and have been shown to decrease skeletal-related events by 30-40% in breast cancer patients. However, these agents also cause a decrease in markers of bone formation, and have been associated with osteonecrosis of the jaw and renal toxicity. The development of safe anabolic agents to stimulate the formation of new bone may be an effective treatment option for patients with bone metastases. Our previous studies using a soluble form of the extracellular domain of the activin type IIA receptor (ActRIIA) fused to a murine IgG-Fc fragment (RAP-011) in murine models of breast cancer metastases have demonstrated that treatment with an activin antagonist can prevent both skeletal and visceral metastases, prolong survival, and increase bone mass.&amp;#x2028; ACE-011, the human analog of RAP-011, is currently in clinical development for the treatment of bone loss in a variety of disease indications. In a recent single-dose, dose-escalating Phase 1 study in healthy postmenopausal women, administration of ACE-011 demonstrated rapid and sustained dose-dependent increases in the bone formation biomarker, bone-specific alkaline phosphatase (BSAP), as well as dose-dependent decreases in bone resorption biomarkers, C-terminal type 1 telopeptide (CTX) and tartrate-resistant acid phosphatase isoform-5b (TRACP-5b).&amp;#x2028; The increased production of follicle stimulating hormone (FSH) in postmenopausal women in response to activin stimulation is well-established. In this study, ACE-011 treatment in postmenopausal women was associated with a rapid and dose-dependent decrease in serum FSH levels consistent with inhibition of activin. By day 8 after a single dose, a mean percent decrease in FSH from baseline of -15%, -27% and -45% was seen in subjects treated at the 0.3, 1 and 3 mg/kg IV dose levels, respectively. By day 15, a mean percent increase in BSAP from baseline of 15%, 19% and 36% was seen in subjects treated at the corresponding dose levels. Pharmacokinetic-pharmacodynamic Emax modeling was utilized to describe the relationship between ACE-011 exposure and FSH suppression and BSAP stimulation.&amp;#x2028; Taken together, these data support the evaluation of ACE-011 as a novel anabolic agent with the potential to provide a therapeutic benefit in patients with metastatic breast cancer at risk for skeletal complications. Serum FSH levels can be used as a biologically relevant marker of activin inhibition in postmenopausal women treated with ACE-011. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1160.

Improvement in Biomarkers of Bone Formation During Infliximab Therapy in Pediatric Crohn's Disease: Results of the REACH Study

Crohn's disease (CD) is associated with altered bone metabolism. This study examined changes in bone formation and resorption after infliximab induction and associations between bone biomarkers, linear growth, and disease activity (Pediatric Crohn's Disease Activity Index [PCDAI]) after 54 weeks of infliximab therapy. One hundred twelve subjects ages 6-17 years with moderate to severe CD received infliximab induction (5 mg/kg/dose) at weeks 0, 2, and 6; week-10 responders were randomized to infliximab every 8 or every 12 weeks maintenance therapy. Serum bone-specific alkaline phosphatase (BSAP), N-terminal propeptide of type 1 collagen (P1NP), urine C-telopeptide of collagen cross-links (CTX-1), and deoxypyrodinoline (DPD) were collected at baseline and 10 weeks. PCDAI and height z-scores were assessed at baseline and at 10 and 54 weeks. Models were adjusted for bone age, gender, height, and steroid use. Baseline BSAP and P1NP levels were negatively associated with PCDAI (both P = .01). BSAP and P1NP increased during induction (both P < .001) and were associated with 54-week increases in height z-score (P < .05 and P < .001, respectively). Improvements in P1NP were associated with 54-week decreases in PCDAI (P = .01). CTX-1 and DPD also increased during induction (P < .001 and P = .01, respectively) but were not associated with changes in PCDAI. Changes in CTX-1 were associated with improvements in height z-score (P < .002). Infliximab therapy is associated with dramatic increases in BSAP and P1NP, consistent with inhibition of tumor necrosis factor-alpha effects on osteoblasts. The increases in CTX-1 and DPD likely reflect coupling of bone formation and resorption and increases in linear growth.

Efficacy and safety of sevelamer hydrochloride and calcium acetate in patients on peritoneal dialysis

Inadequate phosphorus control is associated with increased morbidity and mortality in patients with CKD stage 5. Although phosphate binders are often used in patients on peritoneal dialysis (PD), no large randomized controlled studies evaluating their use solely in this population have previously been reported. In this multicentre, open-label study, adult patients on PD with serum phosphorus >5.5 mg/dl were randomized (2:1) to 12 weeks of treatment with sevelamer hydrochloride or calcium acetate. Doses were titrated to achieve serum phosphorus of 3.0-5.5 mg/dl. Changes in serum phosphorus, calcium, intact parathyroid hormone (iPTH), lipids and plasma biomarkers were assessed. A total of 253 patients were screened, 143 of whom were randomized (sevelamer hydrochloride, n = 97; calcium acetate, n = 46). Treatment groups were well balanced with regard to baseline demographics. Serum phosphorus levels were significantly reduced after 12 weeks with both sevelamer hydrochloride and calcium acetate (P < 0.001). Serum PTH was also reduced in both groups while serum calcium increased in the calcium acetate group (P = 0.001) but not in the sevelamer hydrochloride group. Sevelamer hydrochloride was also associated with decreases in total cholesterol, low-density lipoprotein cholesterol and uric acid and an increase in bone-specific alkaline phosphatase (all P < 0.001 versus baseline). Both treatments were well tolerated and safety profiles were consistent with previous reports in haemodialysis patients. Hypercalcaemia was experienced by more calcium acetate-treated patients (18 versus 2%; P = 0.001). In summary, sevelamer hydrochloride provides a reduction in serum phosphorus compared to that obtained with calcium-based binders in PD patients. The effects of sevelamer hydrochloride appear similar in both PD and haemodialysis populations.

Effects of Lowering Dialysate Calcium Concentration on Mineral Metabolism and Parathyroid Hormone Secretion: A Multicentric Study

This prospective study was conducted with the aim of examining the efficacy of lowering dialysate calcium (dCa) in order to: (i) stimulate bone turnover in hemodialysis patients with biochemical signs of adynamic bone disease (ABD) (hypercalcemia, normal alkaline phosphatase and intact parathyroid hormone (iPTH) <150 pg/mL); and (ii) diminish hypercalcemia in patients with secondary hyperparathyroidism (sHPT) (hypercalcemia, high alkaline phosphatase and iPTH > 400 pg/mL), thus permitting the use of calcium-containing phosphorus binders and vitamin D metabolites. Patients were divided into: an ABD-treated group (24 patients), a sHPT-treated group (18 patients), an ABD-control group (12 patients) and a sHPT-control group (11 patients). For the ABD- and sHPT-treated patients, hemodialysis was conducted with dCa 1.5 mmol/L for three months and then with dCa 1.25 mmol/L for an additional three months, while in the control groups hemodialysis was conducted with dCa 1.75 mmol/L during the entire study. Reduction of dCa in patients with ABD caused a slight but insignificant decrease of Ca, but a significant and permanent increase of bone-specific alkaline phosphatase and intact parathyroid hormone level serum levels. Reduction of dCa in patients with sHPT slightly but insignificantly decreased Ca and intact parathyroid hormone level values. Nevertheless, this enabled the calcium-based phosphate binder dose to be raised and vitamin D3 metabolites to be introduced. Logistic regression analysis indicated that milder bone disease (both ABD and sHPT) was associated with more the favorable effect of dCa reduction. Thus, low dCa stimulated parathyroid glands and increased bone turnover in ABD patients, and enabled better control of mineral metabolism in sHPT patients.

Assessment Of A Nutrient-Based Approach On Bone Health

Background: Complementary and alternative medicine use in adults with, or at risk for, osteopenia is common. Although most of the herbs and supplements appear to be fairly safe, there is insufficient evidence that demonstrates their beneficial effects. Aim of the Study: This study was done to determine whether the current nutrients improve indicators of calcium metabolism and bone status. Materials and Methods: This human clinical trial was randomized, double-blind, placebo-controlled, and prospective in design. Of a population of 72 individuals who were screened over the telephone, 47 post-menopausal females age 50-75 were included in the study. The enrolled subjects were randomly assigned to receive the active product or placebo, one capsule four times per day for six weeks. The major outcome variables were 24-hour urinary calcium per gram of creatinine, serum Bone Specific Alkaline Phosphatase (BSAP), C-Terminal Telopeptide (CTX), and Osteocalcin (OST). Results: At the conclusion of the study, subjects who received the active product showed reduction in the 24-hour urinary calcium loss and serum CTX levels. They revealed an increase in BSAP and no change was noted for OST. Conclusions: Nutrient-based supplementation is able to improve measures of calcium metabolism and bone health in postmenopausal females. Studies of longer duration using endpoints including fracture incidence and bone densitometry should be conducted in the future.

Retracted: A randomized clinical trial of the effects of isosorbide mononitrate on bone formation and resorption in post-menopausal women: a pilot study

Nitric oxide (NO) stimulates bone formation and inhibits bone resorption in vitro. NO donors (nitrates) are inexpensive and widely available, but their value for post-menopausal osteoporosis has never been evaluated in a randomized trial. The objective of this study was to compare the effects of 5 and 20 mg of isosorbide mononitrate (ISMO) on markers of bone turnover in post-menopausal women. A prospective randomized trial was carried out in the Department of Obstetrics & Gynecology, Ain Shams University, Egypt. The study included 50 healthy post-menopausal women with a hip bone mineral density T score between 0 and -2.5. Participants were randomly assigned to 5 or 20 mg/day of ISMO for 12 weeks. Urine N-telopeptide (NTx), a marker of bone resorption, and serum bone-specific alkaline phosphatase (BSALP), a marker of bone formation, were measured. Markers were measured immediately before randomization and after 12 weeks of treatment. The percent change in NTx and BSALP for each of the treatment groups (5 mg ISMO and 20 mg ISMO) was calculated. The main outcome measures were serum NTx and BSALP in the 5 and 20 mg ISMO groups after 12 weeks of treatment. Women adhering to 20 mg of ISMO had a 42.03% (95% confidence interval (CI), 20.1-73.7) reduction in NTx and a 29.05% (95% CI, 10.8-48.4) increase in BSALP, and women adhering to 5 mg of ISMO had a 31.12% (95% CI, 8.3-68.2) reduction in NTx and a 28.4% (95% CI, 4.6-52.1) increase in BSALP. ISMO, as a NO donor, may be useful for the prevention of post-menopausal osteoporosis.

Response to bortezomib is associated to osteoblastic activation in patients with multiple myeloma

The prompt response to bortezomib observed in a 63-year-old woman with multiple myeloma was associated with a significant increase in alkaline phosphatase (ALP). After similar elevations were noted in patients responding to bortezomib, thalidomide, dexamethasone combination, ALP levels were analysed in two large bortezomib trials. A statistically significant elevation of ALP from baseline was observed in responding patients (complete and partial responders) within three cycles of therapy. The rise in ALP after bortezomib in three patients was explained by a parallel increase in bone-specific ALP and parathyroid hormone, suggesting that response to bortezomib in myeloma is closely associated with osteoblastic activation.

A prospective study of changes in bone turnover and bone density associated with regaining weight in women with anorexia nervosa

Anorexia nervosa (AN) is a condition of self-induced weight loss, associated with an intense fear of gaining weight. Previous studies have shown that bone density may increase with regaining and maintaining normal weight; however, relatively little is known about the changes in bone metabolism that occur during weight restoration. We describe the effect of weight restoration and maintenance of weight over 1 year on bone mineral density (BMD) and bone turnover. We recruited women from the eating disorders services at the South West London and St George's Mental Health NHS Trust, and the Priory and Charter Nightingale Hospitals in London, UK. Details of their AN, fracture history, menstrual history and exercise were obtained by interview and case note review. Morning samples of blood and second void urine were taken for biochemical analysis. BMD was measured by DXA at the lumbar spine (LS), femoral neck (FN), distal radius (RD) and total body bone mineral content (BMC). Patients then entered the treatment program, which includes re-feeding, dietary education and psychotherapy. Over a period of 42 months, we recruited 55 women who agreed to participate in this study and underwent baseline investigations. Of these, 15 (27%) subjects achieved and then maintained their target weight for the duration of the study. At baseline for all subjects (n=55) estradiol levels were lower than the normal reference ranges (both follicular and luteal phases) in 91% of the women. Bone specific alkaline phosphatase (BSAP) concentrations were lower than the premenopausal reference range in 55% of women, and urinary deoxypyridinoline (DPD) was above the premenopausal reference range in 78% of women. Baseline lumbar spine BMD was positively related to BMI (Pearson's r=0.29, P=0.04) and inversely related to bone turnover markers: urinary DPD (Pearson's r=-0.39, P=0.01 and serum BSAP (Pearson's r=-0.3, P=0.06). The 15 patients who regained and maintained weight were followed-up for a mean duration of 69 weeks (SD 7.3, range 54 to 84 weeks). Mean BMI increased from 14.2 (1.7) to 20.2 (0.77) kg/m2 and remained stable throughout follow-up. Menstruation resumed in 8 of the 15 women. Total body BMC and LS BMD increased significantly over the duration of follow-up (by 4.3% each), but FN BMD and distal radius remained stable. Lumbar spine bone area also increased significantly, whereas FN and distal radius did not. These changes were associated with a significant increase in BSAP (P=0.01), and a non-significant trend for a decrease in DPD (P=0.10). Our findings suggest that when women are at low body weight they are in a hypo-estrogenic state, which is associated with imbalance of bone turnover (high bone resorption and low bone formation). This is reversed with weight gain and persists as target weight is maintained and is associated with increases in BMC and BMD.

Response to bortezomib (BOR) and bone metabolism in multiple myeloma patients

6536 Background: Evidence of osteoblastic activation was first observed at our Institution in patients with progressive multiple myeloma (MM) during treatment with bortezomib (VELCADE). Osteoblastic activation, based on isolated alkaline phosphatase (ALP) elevation (without alteration of other liver function tests) with a parallel increase in bone specific ALP and parathyroid hormone, was noted to be associated to response. ALP variation was subsequently assessed in 182 MM patients treated with BOR on the SUMMIT trial. A significant difference in isolated ALP elevation was observed in patients achieving ≥ PR (≥50% paraprotein reduction using EBMT criteria) compared to the other patients (P = 0.02). Methods: In this study we report ALP variation in 584 patients with normal liver function at baseline and treated in the randomized open label phase III APEX trial (Millennium protocol M34101–039). Patients with relapsed or progressive disease after at least one prior therapy were enrolled in the study, which c...