A comparison of teriparatide and calcitonin therapy in postmenopausal Asian women with osteoporosis: a 6-month study

Effects of Teriparatide versus Salmon Calcitonin Therapy for the Treatment of Osteoporosis in Asia: A Meta-analysis of Randomized Controlled Trials

Objective:

The objective of this meta-analysis was to compare the efficacy and safety of teriparatide versus salmon calcitonin for the treatment of osteoporosis in Asian patients and to investigate whether the results of global studies could be applicable to Asian patients.

Methods:

PubMed, OVID, Cochrane Central Register of Controlled Trials (CENTRAL) and EMBASE up to December 2018 were searched. Eligible randomized controlled trials (RCTs) that compared teriparatide versus salmon calcitonin in Asian osteoporosis population were included. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used for data synthesis, and Cochrane Collaboration software Review Manager 5.3 was used to analyze the pooled data.

Results:

Three RCTs involving 529 patients were included (mean age 68.7 yr; 93.4% females; mean follow-up 6 months); outcome measures included bone mineral density (BMD) of the femoral neck, total hip and lumbar spine; bone markers and adverse events. We found that the period of 6-months of teriparatide treatment was helpful for the improvement of the BMD of lumbar vertebra, however, the improvement of BMD was not significant in the femoral neck and total hip joint. There was a positive correlation between bone-specific alkaline phosphatase (BSAP) and osteocalcin (OCN) and the response of Asian patients to subcutaneous injection of 20 micrograms per day of teriparatide. The proportion of the occurrence of adverse effects was more obvious in the teriparatide group compared with salmon calcitonin, but there was no significant difference.

Conclusion:

Results suggested that the use of teriparatide could improve the lumbar BMD by shortterm (six months) application in Asian osteoporosis patients, which is beneficial to the patients who cannot tolerate adverse events of long-term treatment. The BSAP and OCN bone markers could be useful to monitor the responses of Asian osteoporosis patients to teriparatide treatment. Finally, both of teriparatide and salmon calcitonin were well tolerated by Asian patients.

The efficacy of teriparatide on lumbar spine bone mineral density, vertebral fracture incidence and pain in post-menopausal osteoporotic patients: A systematic review and meta-analysis

Objective

Teriparatide has been increasingly utilized in the management of osteoporosis. The efficacy of low and high dose teriparatide on lumbar spine bone mineral density, vertebral fracture incidence and pain is unknown. We sought to determine the efficacy of teriparatide on these patient-important outcomes using a systematic review and meta-analysis.

Methods

A systematic search of electronic databases (MEDLINE, EMBASE, CENTRAL, CINAHL) was performed to identify randomized controlled trials (RCTs) that evaluate teriparatide to any comparator for the treatment of osteoporosis in postmenopausal women. The Grades of Recommendation Assessment, Development and Evaluation (GRADE) criteria were used by two independent reviewers to assess the strength and quality of evidence.

Results

A total of 20 studies (n = 6024) were included in this review, with 2855 patients receiving teriparatide and 3169 patients receiving placebo or control treatment. A teriparatide dose of 20 μg/day increased lumbar spine bone mineral density (BMD) (standardized mean difference (SMD) 0.34 standard deviation (SD) units higher (95% CI 0.19–0.48 SDs higher) in comparison to placebo. Relative to anti-resorptive agents, 20 μg/day of teriparatide had a range from 0.14 SD units to 0.96 SD units higher (95% CI, 0.08 SDs lower to 0.36 SDs higher, CI, 0.33–1.59 SDs higher, respectively). 20 μg/day teriparatide had a significant effect on pain severity to placebo or control (SMD 0.80, 95% CI, 1.16–0.43 SDs lower) and also decreased the incidence of vertebral fractures compared to placebo (relative risk 0.31, 95% CI 0.21 to 0.46). Arthralgia and extremity pain incidence were also calculated; there were 15 and 8 fewer events per 1000 patients with the use of 20 μg/day of teriparatide compared to placebo or control, respectively.

Conclusion

High quality evidence supports the utilization of teriparatide 20 μg/day dose to significantly improve lumbar spine BMD and decrease incidence of vertebral fractures and pain severity relative to all comparators. 40 μg/day dose of teriparatide demonstrated significantly better results with prolonged treatment. This data is valuable for clinicians involved in the care of this growing demographic of patients. Further investigation on the safety and efficacy of teriparatide in higher doses for the long-term treatment of osteoporosis in postmenopausal women should be conducted through high-quality clinical trials.

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Teriparatide (20 μg/day) significantly improves lumbar spine bone mineral density.

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Teriparatide (20 μg/day) reduces vertebral fracture incidence and pain.

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Increased teriparatide dose (40 μg/day) may have even greater clinical efficacy.

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Further investigation on safety profiles for longer-term treatment is warranted.

Effects of teriparatide on hip and upper limb fractures in patients with osteoporosis: A systematic review and meta-analysis

In randomized clinical trials (RCTs) with teriparatide, the number of patients with incident hip fractures was small and insufficiently powered to show statistically significant differences between groups. We, therefore, conducted a systematic review and meta-analysis of the efficacy of teriparatide in the reduction of hip and upper limb fractures in women and men with osteoporosis. A comprehensive search of databases until 22 November 2017 was conducted for RCTs of at least 6-month duration that reported non-spine fractures (hip, humerus, forearm, wrist), either as an efficacy or safety endpoint. Only RCTs that included patients with the approved treatment indications and dose for use of teriparatide were included; trials with off-label use of teriparatide were excluded. Two independent reviewers performed study selection and data extraction. Statistical procedures included Peto's method and Mantel-Haenszel with empirical correction, as most of the RCTs reported zero events in at least one of the treatment arms. Study results are expressed as odds ratios (OR) with 95% confidence intervals (CI). Publication bias and heterogeneity were evaluated with standard statistical tests. Twenty-three RCTs were included, 19 with an active-controlled arm (representing 64.9% of the patients included in the control group) and 11 double-blind, representing data on 8644 subjects, 3893 of them treated with teriparatide. Mean age (SD) was 67.0 (4.5) years, median treatment duration 18 months (range: 6 to 24 months). A total of 34 incident hip, 31 humerus, 31 forearm, and 62 wrist fractures were included. Meta-analysis results showed an OR (95% CI) for hip fractures of 0.44 (0.22-0.87; p = 0.019) in patients treated with teriparatide compared with controls. The effects on the risk of humerus [1.02 (0.50-2.08)], forearm [0.53 (0.26-1.08)] and wrist fractures [1.21 (0.72-2.04)] were not statistically significant (p > 0.05). This meta-analysis provides evidence of efficacy of teriparatide in reducing hip fractures by 56% in patients with osteoporosis.

Efficacy and Safety of the Biosimilar Recombinant Human Parathyroid Hormone Cinnopar® in Postmenopausal Osteoporotic Women: A Randomized Double-blind Clinical Trial

BACKGROUND

Due to high cost and burden of osteoporosis, it is reasonable to focus on the reduction of fractures as the main goal of treatment. We compared the efficacy and safety of a new biosimilar recombinant human parathyroid hormone (CinnoPar®, CinnaGen, Iran) to the reference product (Forteo®, Eli Lilly, USA) in a randomized double-blind clinical trial (RCT).

METHODS

Overall, 104 osteoporotic postmenopausal women aged 45-75 yr were randomized to receive 20 μg daily subcutaneous injections of either Forteo® or CinnoPar® for 6-months from 2011-2012. Bone biomarkers were measured at baseline, and during first, third, and sixth month's follow-up along with lumbar spine, total hip, and femoral neck bone mineral density (BMD) assessment at the baseline and six months after that. The study was registered in Iranian registry of clinical trials under the registration number of IRCT138810121414N5. The endpoints were to compare bone biomarkers, BMD and drug safety between groups. Data analysis was performed using SPSS 11.

RESULTS

Age range of ninety-four patients who completed the study was 42-81 yr. Participants were divided into Forteo (45 subjects) and CinnoPar (49 subjects) groups. No significant difference in terms of bone biomarkers or BMD scores was shown between groups (P≥0.05). The most prevalent side effects were hypercalcemia and hypercalciuria without any significant statistical differences between groups.

CONCLUSION

CinnoPar® can be considered as a good alternative therapy for Forteo® in postmenopausal osteoporotic women due to its comparable efficacy and safety properties.

Back pain in patients with severe osteoporosis on teriparatide or antiresorptives: a prospective observational study in a multiethnic population

INTRODUCTION

We evaluated reduced back pain in a multiethnic population treated with teriparatide and/or antiresorptives in real-life clinical settings over 12 months.

METHODS

This prospective observational study comprised 562 men and postmenopausal women (mean age 68.8 years) receiving either teriparatide (n = 230), antiresorptives (raloxifene or bisphosphonates; n = 322), or both (n = 10) for severe osteoporosis. The primary endpoint was the relative risk of new/worsening back pain at six months.

RESULTS

At baseline, a higher proportion of teriparatide-treated than antiresorptive-treated patients had severe back pain (30.9% vs. 17.7%), extreme pain/discomfort (25.3% vs. 16.8%), extreme anxiety/depression (16.6% vs. 7.8%) and were confined to bed (10.0% vs. 5.3%). Teriparatide-treated patients had higher visual analog scale (VAS) scores for pain (5.8 ± 2.42 vs. 5.1 ± 2.58) and lower mean European Quality of Life-5 Dimensions (EQ-5D) scores (37.7 ± 29.15 vs. 45.5 ± 31.42) than antiresorptive-treated patients. The incidence of new/worsening back pain at six months for patients on teriparatide and antiresorptives was 9.8% and 10.3% (relative risk 0.99, 95% confidence interval 0.80-1.23), respectively. The incidence of severe back pain at 12 months was 1.3% and 1.6% in the teriparatide and antiresorptive treatment groups, respectively. Teriparatide-treated patients had lower mean VAS (2.71 ± 2.21 vs. 3.30 ± 2.37) and EQ‑5D (46.1 ± 33.18 vs. 55.4 ± 32.65) scores at 12 months. More teriparatide-treated patients felt better (82.7% vs. 71.0%) and were very satisfied with treatment (49.4% vs. 36.8%) compared to antiresorptive-treated patients.

CONCLUSION

Patients treated with either teriparatide or antiresorptives had similar risk of new/worsening back pain at six months.

Epidemiology and treatment of osteoporosis in women: an Indian perspective

The number of women with osteoporosis, ie, with reduced bone mass and the disruption of bone architecture, is increasing in India. While data on prevalence of osteoporosis among women in India come from studies conducted in small groups spread across the country, estimates suggest that of the 230 million Indians expected to be over the age of 50 years in 2015, 20%, ie, ~46 million, are women with osteoporosis. Thus, osteoporosis is a major public health problem in Indian women. Low calcium intakes with extensive prevalence of vitamin D deficiency, increasing longevity, sex inequality, early menopause, genetic predisposition, lack of diagnostic facilities, and poor knowledge of bone health have contributed toward the high prevalence of osteoporosis. Bone health may be optimized by creating an environment to achieve peak bone mass during adolescence, maintenance of healthy bone throughout the life cycle, and prevention of bone loss postmenopausal. In Indian women, calcium, vitamin D, and bisphosphonates are the commonest first-line therapies used. The use of other drugs such as hormone replacement therapy, estrogen agonists, calcitonin, parathyroid hormone, and denosumab is decided as per the affordability and availability of treatment options. Major gaps still remain in the diagnosis and management of osteoporosis, thus highlighting the need for more structured research in this area. This review focuses on the epidemiology of osteoporosis in Indian women and available treatments.

A systematic review on the use of daily subcutaneous administration of teriparatide for treatment of patients with osteoporosis at high risk for fracture in Asia

This systematic review aimed to examine the evidence for teriparatide in Asia for osteoporosis with a high fracture risk and for exploratory (unapproved) bone-related indications. MEDLINE (1946+), EMBASE (1966+), and ClinicalTrials.gov (2008+) were searched (16 August 2013); all studies of daily subcutaneous teriparatide 20 μg for bone-related conditions from China, Hong Kong, Japan, Republic of Korea, Philippines, Singapore, and Taiwan were included. Evidence on efficacy/safety was retrieved primarily from randomized controlled trials (10 publications) of postmenopausal women from Japan and China. In these studies, teriparatide was well tolerated; subjects had significantly greater increases in lumbar spine bone mineral density (BMD) from baseline compared with placebo, antiresorptive agents, or elcatonin/calcitonin; bone turnover markers increased from baseline and were sustained at elevated levels during teriparatide treatment. Few studies reported fracture risk, pain, or quality of life; one study showed a lower incidence of new-onset vertebral fracture with teriparatide versus antiresorptive agents. Nonrandomized studies (nine publications, one unpublished trial) conducted mainly in Taiwan, Japan, and the Republic of Korea provided supporting data for efficacy. The exploratory (unapproved) use of teriparatide (17 publications) for fracture healing and osteonecrosis of the jaw was described primarily in case reports. The clinical effectiveness of teriparatide for treatment of postmenopausal women with osteoporosis who are at high risk of fracture in Asia is focused primarily on improvements in BMD and tolerability. Recommended additional studies may include assessment of fracture risk and the effect of teriparatide on pain, quality of life, and mortality in Asia.

Literature review: The effects of teriparatide therapy at the hip in patients with osteoporosis

Teriparatide is a skeletal anabolic treatment for patients with osteoporosis at high risk for fracture. Because adequate clinical trials have not yet been conducted to assess the efficacy of teriparatide for reducing the risk of hip fracture, we review here the literature regarding how treatment with teriparatide affects the hip in patients with osteoporosis. Teriparatide increases cancellous bone volume, improves bone architecture, and - uniquely among osteoporosis treatments - increases cortical thickness and cortical porosity. By bone scan and positron emission tomography, teriparatide increases bone formation throughout the skeleton, including the hip. Consistent with these findings, studies using dual-energy X-ray absorptiometry and quantitative computed tomography for longitudinal assessment of changes at the hip have consistently shown increases in areal and volumetric bone mineral density, cortical thickness, and finite element-estimated hip strength in patients treated with teriparatide. Finally, in clinical fracture-outcome trials, treatment with teriparatide has been shown to reduce the risk of nonvertebral fracture, a composite endpoint that includes hip fracture. Taken together, this body of evidence suggests that teriparatide positively affects the hip in patients with osteoporosis.

PEGylation site-dependent structural heterogeneity study of monoPEGylated human parathyroid hormone fragment hPTH(1-34)

The structures of C- and N-terminally monoPEGylated human parathyroid hormone fragment hPTH(1-34) as well as their unmodified counterparts, poly(ethylene glycol) (PEG) and hPTH(1-34), have been studied by small-angle neutron scattering (SANS). The scattering results show that free hPTH(1-34) in 100 mM phosphate buffer (pH 7.4) aggregates into clusters. After conjugation with PEG, the PEG-peptide conjugates self-assemble into a supramolecular core-shell structure with a cylindrical shape. The PEG chains form a shell around the hPTH(1-34) core to shield hPTH(1-34) from the solvent. The detailed structural information on the self-assembled structures is extracted from SANS using a model of the cylindrical core with a shell of Gaussian chains attached to the core surface. On the basis of the data, because of the charge-dipole interactions between the conjugated PEG chain and the peptide, the conjugated PEG chain forms a more collapsed conformation compared to free PEG. Moreover, the size of the self-assembled structures formed by the C-terminally monoPEGylated hPTH(1-34) is about 3 times larger than that of the N-terminally monoPEGylated hPTH(1-34). The different aggregation numbers of the self-assembled structures, triggered by different PEGylation sites, are reported. These size discrepancies because of different PEGylation sites could potentially affect the pharmacokinetics of the hPTH(1-34) drug.

Normocalcemic primary hyperparathyroidism in a patient with severe osteoporosis receiving teriparatide

We describe here the case of an elderly female with severe osteoporosis, who presented with a worsening backache, following teriparatide treatment. She was subsequently diagnosed to have normocalcemic primary hyperparathyroidism. Before prescribing teriparatide, an appropriate endocrine evaluation must be undertaken by all healthcare physicians (serum intact parathyroid hormone (iPTH) level), despite having a normal serum calcium. Normocalcemic hyperparathyroidism should be considered as an important alternate cause for osteoporosis.

Osteoanabolics

Osteoporosis is characterized by reduced bone mass, impaired bone quality, and a propensity to fracture. An "osteoanabolic" should be referred to any therapy that helps increase bone mass. Bone mass represents 80% of bone mechanical strength. A low bone mass therefore provides the strongest association of future risk of fracture. This review aims to discuss all available and future therapies that attempt to increase bone mass be it organic or inorganic.

Teriparatide - Indications beyond osteoporosis

Osteoporosis is a condition of impaired bone strength that results in an increased risk of fracture. The current and most popular pharmacological options for the treatment of osteoporosis include antiresorptive therapy, in particular, oral bisphosphonates (alendronate, risedronate, ibandronate). Anabolic agents like teriparatide have widened our therapeutic options. They act by directly stimulating bone formation and improving bone mass quantity and quality. Two forms of recombinant human parathyroid hormone (PTH) are available : full-length PTH (PTH 1-84; approved in the EU only) and the 1-34 N-terminal active fragment of PTH (teriparatide, US FDA approved). This review aims to discuss the benefits of teriparatide beyond the currently licensed indications like fracture healing, dental stability, osteonecrosis of jaw, hypoparathyroidism, and hypocalcemia.

Teriparatide: Its Use in the Treatment of Osteoporosis

The prevalence of osteoporosis is likely to rise with the increase in life expectancy of an ageing population. Current first line therapies for the treatment of osteoporosis are predominantly anti-resorptive. Teriparatide is a first in class, anabolic agent with a unique mechanism that results in increased bone formation. Daily subcutaneous injection for 6–24 months was effective in reducing vertebral and non-vertebral fracture rates, in improving bone mineral density (BMD) and in increasing bone formation rates in postmenopausal osteoporosis, with effects persisting following treatment cessation. Similar benefits on bone mass and bone formation were seen in men with osteoporosis and glucocorticoid induced osteoporosis. Beneficial effects on bone mass have been demonstrated in treatment naive subjects treated with teriparatide alone, sequentially with anti-resorptive therapy and concomitantly with some, but not all, anti-resorptive treatments due to an early blunting of the anabolic effect. Teriparatide is generally well tolerated. However, the high treatment cost and inconvenient mode of administration has limited it's use to patients with osteoporosis who have experienced an unsatisfactory response, who are intolerant to other osteoporosis therapies, or to patients at very high risk of fracture. Teriparatide treatment is currently restricted to a total lifetime treatment dose of 18 months of daily subcutaneous therapy due to concerns from animal studies suggesting an increased risk of osteosarcoma. More safety data may permit a longer duration of treatment in the future but will necessitate prolonged human studies. Teriparatide may serve a more prominent role in the treatment of older patients who continue to fracture despite low bone turnover or sustain side effects with anti-resorptive therapy.

Osteoclast activity and subtypes as a function of physiology and pathology--implications for future treatments of osteoporosis

Osteoclasts have traditionally been associated exclusively with catabolic functions that are a prerequisite for bone resorption. However, emerging data suggest that osteoclasts also carry out functions that are important for optimal bone formation and bone quality. Moreover, recent findings indicate that osteoclasts have different subtypes depending on their location, genotype, and possibly in response to drug intervention. The aim of the current review is to describe the subtypes of osteoclasts in four different settings: 1) physiological, in relation to turnover of different bone types; 2) pathological, as exemplified by monogenomic disorders; 3) pathological, as identified by different disorders; and 4) in drug-induced situations. The profiles of these subtypes strongly suggest that these osteoclasts belong to a heterogeneous cell population, namely, a diverse macrophage-associated cell type with bone catabolic and anabolic functions that are dependent on both local and systemic parameters. Further insight into these osteoclast subtypes may be important for understanding cell-cell communication in the bone microenvironment, treatment effects, and ultimately bone quality.

Oral salmon calcitonin--pharmacology in osteoporosis

IMPORTANCE OF THE FIELD

Osteoporosis is a slow progressive disease with develops over decades, and where intervention is needed for an extended number of years. This highlights the need for safe intervention possibilities, which have sustained beneficial effects post-treatment.

AREAS COVERED IN THIS REVIEW

Articles on salmon calcitonin appearing on Pubmed from 1960 until today, with focus on a newly developed oral formulation showing increased exposure and efficacy compared with nasal formulation is reviewed. The second half focuses on long-term phenomena, such as bone quality and resolution effects. The final part discusses potential additional benefits of salmon calcitonin.

WHAT THE READER WILL GAIN

Insight into the clinical development of an orally formulated peptide, as well as a detailed understanding of why this approach could revive salmon calcitonin as a treatment for osteoporosis.

TAKE HOME MESSAGE

The oral formulation of salmon calcitonin provides additional benefits and increased efficacy on bone based on Phase I and II clinical trials data, as compared with the nasal formulation. Hence, the results on the ongoing Phase III fracture trial are awaited with great interest.

Effects of teriparatide on bone mineral density and bone turnover markers in Japanese subjects with osteoporosis at high risk of fracture in a 24-month clinical study: 12-month, randomized, placebo-controlled, double-blind and 12-month open-label phases

This multicenter study assessed the safety and efficacy of teriparatide 20 microg/day in Japanese men and women with osteoporosis at high risk of fracture during a 12-month, randomized, double-blind, placebo-controlled treatment period followed by second and third treatment periods (to 18 and 24 months, respectively,) in which all subjects received open-label teriparatide. Subjects (93% female; median age 70 years) were randomized 2:1 to teriparatide versus placebo (randomized at baseline, teriparatide n=137, placebo-teriparatide n=70; entering the second period, teriparatide n=119, placebo-teriparatide n=59; entering the third period, teriparatide n=102, placebo-teriparatide n=50). For subjects with measurements at 12 months, teriparatide significantly increased bone mineral density (BMD) at the lumbar spine L2-L4 (mean percent change+/-SD, teriparatide 10.04+/-5.23% versus placebo-teriparatide 0.19+/-4.33%), the femoral neck (teriparatide 2.01+/-4.63% versus placebo-teriparatide 0.44+/-3.97%), and the total hip (teriparatide 2.72+/-4.04% versus placebo-teriparatide -0.26+/-3.42%). In the placebo-teriparatide group at 24 months (12-month teriparatide dosing) BMD increased by 9.11+/-5.14% at the lumbar spine, 2.19+/-4.81% at the femoral neck and 2.46+/-3.54% at the total hip. In the teriparatide group at 18 and 24 months, BMD increased from baseline at the lumbar spine by 11.93+/-5.79% and 13.42+/-6.12%, respectively; at the femoral neck by 2.68+/-4.45% and 3.26+/-4.25%, respectively; and at the total hip by 3.02+/-3.79% and 3.67+/-3.98%, respectively. Serum procollagen I N-terminal pro-peptide (PINP) increased rapidly with teriparatide treatment (P<0.001 versus placebo at 1 month) and changed from baseline in the teriparatide and placebo-teriparatide groups at 12 months by a median of 78.95% and -17.23%, respectively, (P<0.001) and at 24 months by 49.24% and 76.12%, respectively. The incidence of treatment-emergent adverse events (TEAEs), serious TEAEs, and discontinuations due to TEAEs were comparable in the teriparatide and placebo-teriparatide groups. These data show that teriparatide 20 microg/day was well tolerated and stimulated bone formation in Japanese subjects with osteoporosis at high risk of fracture during 18 and 24 months of treatment.

Effect of teriparatide [rhPTH(1,34)] and calcitonin on intertransverse process fusion in a rabbit model

STUDY DESIGN

Randomized, double-blinded, placebo controlled animal study.

OBJECTIVE

To evaluate the effect of teriparatide and calcitonin after an intertransverse process spinal fusion in a rabbit model.

SUMMARY OF BACKGROUND DATA

It is widely recognized that some osteoporosis medications, including bisphosphonates, can interfere with bone healing. Although prescribed frequently in the treatment of osteoporosis, the effect of teriparatide and calcitonin on spinal fusion has not been fully elucidated. We hypothesized that teriparatide, being the only anabolic medication for osteoporosis treatment, would have a beneficial effect on spine fusion.

METHODS

Fifty-one New Zealand white rabbits underwent a posterolateral L5-L6 intertransverse process arthrodesis using autogenous iliac crest bone graft. The rabbits were randomly divided into 3 groups. All animals received daily subcutaneous injections of group I (n = 17) 1 mL of saline placebo; group II (n = 17) 10 microg/kg/day of teriparatide; group III (n = 17) 14 IU/animal of calcitonin during the 8-week postoperative period. Postmortem analyses included manual palpation, radiographic, biomechanical, and histologic assessment. Three random 10x fields were examined/graded within the cephalad, middle, and caudal regions of each section (810 fields). Fusion quality was graded using the Emery histologic scale (0-7 based on fibrous/bone content of the fusion mass).

RESULTS

Histologic fusion rates for teriparatide averaged 86.7% and was significantly greater than the autograft control group (50%) (P = 0.033). Radiographically, there was a strong trend towards teriparatide being superior to the calcitonin group (85.7% vs. 56.3%, respectively; P = 0.07). The average Emery grading score was 5.99 +/- 1.46 SD for the autologous group and 6.26 +/- 0.93 SD for the teriparatide group (P = 0.031). Although not significant, the teriparatide group showed less motion in flexion/extension, lateral bending, and axial rotation.

CONCLUSION

Our results suggest that teriparatide enhances spinal fusion while calcitonin has a neutral effect. The teriparatide group had the best histologic fusion rate and Emery scores, while the calcitonin group was similar to the saline controls. Although not significant, the teriparatide group had a strong trend towards superior radiographic fusion over the calcitonin group.

Is bone quality associated with collagen age?

The World Health Organization defines osteoporosis as a systemic disease characterized by decreased bone tissue mass and microarchitectural deterioration, resulting in increased fracture risk. Since this statement, a significant amount of data has been generated showing that these two factors do not cover all risks for fracture. Other independent clinical factors, such as age, as well as aspects related to qualitative changes in bone tissue, are believed to play an important role. The term "bone quality" encompasses a variety of parameters, including the extent of mineralization, the number and distribution of microfractures, the extent of osteocyte apoptosis, and changes in collagen properties. The major mechanism controlling these qualitative factors is bone remodeling, which is tightly regulated by the osteoclast/osteoblast activity. We focus on the relationship between bone remodeling and changes in collagen properties, especially the extent of one posttranslational modification. In vivo, measurements of the ratio between native and isomerized C-telopeptides of type I collagen provides an index of bone matrix age. Current preclinical and clinical studies suggests that this urinary ratio provides information about bone strength and fracture risk independent of bone mineral density and that it responds differently according to the type of therapy regulating bone turnover.

Teriparatide: a review of its use in osteoporosis

Recombinant teriparatide (Forteo; Forsteo) is an anabolic (bone forming) agent. Studies have shown that subcutaneous teriparatide 20 microg/day is effective in women with postmenopausal osteoporosis, men with idiopathic or hypogonadal osteoporosis and patients with glucocorticoid-induced osteoporosis. Teriparatide improves bone mineral density (BMD) and alters the levels of bone formation and resorption markers; histomorphometric studies showed teriparatide-induced effects on bone structure, strength and quality. Subcutaneous teriparatide 20 microg/day administered over a treatment period of 11-21 months was effective in reducing the risk of fractures in and in improving BMD in men with idiopathic or hypogonadal osteoporosis, women with postmenopausal osteoporosis and patients with glucocorticoid-induced osteoporosis. Furthermore, the beneficial effects of teriparatide on vertebral fracture prevention and BMD appear to persist following treatment cessation. Teriparatide is generally well tolerated and treatment compliance rates are favourable. However, current limitations on the length of treatment and the high acquisition cost mean that teriparatide is best reserved for the treatment of patients with osteoporosis at high risk of fracture, or for patients with osteoporosis who have unsatisfactory responses to or intolerance of other osteoporosis therapies.

Calcitonin: a drug of the past or for the future? Physiologic inhibition of bone resorption while sustaining osteoclast numbers improves bone quality

Postmenopausal osteoporosis results from a continuous imbalance between bone resorption and bone formation, favoring bone resorption. An increasing number of treatments for osteoporosis are in development and on the market. A range of differences and similarities are found between these treatment options, and these need to be carefully evaluated before the initiation of treatment. This article summarizes data from in vitro and animal studies, as well as clinical trials, on the effect of calcitonin on bone turnover. Calcitonin was found to exert its antiresorptive effects via directly reducing osteoclastic resorption, and thus leads to an increase in bone mineral density and bone strength. Furthermore, calcitonin appears to mainly target the most active osteoclasts, and in contrast to most other antiresorptive agents it does not reduce the number of osteoclasts. Finally, in humans, while attenuating resorption, calcitonin treatment does not interfere markedly with bone formation, in contrast to other currently available antiresorptive agents. Thus, we speculate that calcitonin treatment will lead to a continuously positive bone balance in contrast with other antiresorptive agents currently on the market and thereby, in a physiologic manner, result in improved bone quality. Calcitonin is currently only available in injectable and nasal formulations. An oral formulation may, however, improve patient acceptance and compliance. Currently, several different routes are being pursued to identify an optimal oral formulation, of which the technology based on 5-CNAC is the most advanced. There are promising clinical data available for this formulation from both osteoarthritis and osteoporosis clinical trials, although the antifracture efficacy is not yet known.

Effect of teriparatide on bone mineral density and biochemical markers in Japanese women with postmenopausal osteoporosis: a 6-month dose-response study

The dose-response efficacy and safety with three doses of teriparatide and placebo was assessed, using once-daily subcutaneous injections for 24 weeks, in Japanese postmenopausal women with osteoporosis at high risk of fracture for reasons of preexisting fracture(s), advanced age, and/or low bone mineral density (BMD). In this multicenter, randomized, placebo-controlled study, 159 subjects were randomized and 154 subjects were included for analysis. Teriparatide (10-microg, 20-microg, and 40-microg doses) showed a statistically significant increase with increasing treatment dose as assessed by the percent change of lumbar spine BMD from baseline to endpoint using Williams' test when compared with placebo (P < 0.001). The mean (+/-SD) percent change in lumbar spine, femoral neck, and total hip BMD with the 20-microg dose from baseline to endpoint was 6.40% +/- 4.76%, 1.83% +/- 7.13%, and 1.91% +/- 3.60%, respectively. Rapid and sustained increases in bone formation markers [type I procollagen N-terminal propeptide (PINP), type I procollagen C-terminal propeptide (PICP), and bone-specific alkaline phosphatase (BAP)], followed by late increases in a bone resorption marker [type I collagen cross-linked C-telopeptide (CTX)], were observed for the teriparatide treatment groups (20-microg, 40-microg), suggesting a persistent, positive, balanced anabolic effect of teriparatide. Optimal adherence was achieved by this daily self-injection treatment. Regarding safety, most of the adverse events were mild to moderate in severity. No study drug-or study procedure-related serious adverse events were reported during the treatment period. These results observed in Japanese patients may support the observation that teriparatide stimulates bone formation in patients with osteoporosis at a high risk of fracture.