Alendronate for the treatment of osteoporosis in men

Alendronate Release from UHMWPE-Based Biomaterials in Relation to Particle Size of the GUR Powder for Manufacturing

Ultra-high molecular weight polyethylene (UHMWPE) is widely used in endoprosthetics and has been the subject of countless studies. This project investigates the dependence of alendronate (AL) release on the molecular weight of the UHMWPE used (GUR1020 and GUR1050). A 0.5 wt% AL was added to the UHMWPE during the production of the moldings. In addition to the 14-day release tests, biocompatibility tests such as live dead assay, cell proliferation assay (WST) and Lactate dehydrogenase test (LDH) with MG-63 cells as well as a tensile test according to DIN EN ISO 527 were carried out. The released AL concentration was determined by HPLC. A continuous release of the AL was observed over the entire period of 2 weeks. In addition, a correlation between molar mass and AL release was demonstrated. The GUR1020 showed a release four times higher than the GUR1050. Both materials have no negative influence on the proliferation of MG-63 cells. This was also confirmed in the live/dead assay by the increase in cell count. No cytotoxicity was detected in the LDH test. The addition of 0.5 wt% AL increased the elongation at break for GUR1020 by 23% and for GUR1050 by 49%. It was demonstrated that the choice of UHMWPE has an influence on the release of AL. The particle size in particular has a strong influence on the release behavior.

Design and Biological Evaluation of Delivery Systems Containing Bisphosphonates

Bisphosphonates have found application in the treatment of reoccurrence of bone diseases, breast cancer, etc. They have also been found to exhibit antimicrobial, anticancer and antimalarial activities. However, they suffer from pharmacological deficiencies such as toxicity, poor bioavailability and low intestinal adsorption. These shortcomings have resulted in several researchers developing delivery systems that can enhance their overall therapeutic effectiveness. This review provides a detailed overview of the published studies on delivery systems designed for the delivery of bisphosphonates and the corresponding in vitro/in vivo results.

Analysis of daily teriparatide treatment for osteoporosis in men

The percent and absolute lumbar spine and femoral neck bone mineral densities and absolute procollagen type I N-terminal propeptide (PINP) increases following a 20-μg/day teriparatide treatment for 12 months were similar in men and women regardless of sex differences.

INTRODUCTION

Several placebo-controlled studies have measured the effects of daily teriparatide in men and postmenopausal women with osteoporosis but none have directly compared the effects between these groups. We retrospectively compared the effects of daily teriparatide therapy in men and postmenopausal women with osteoporosis and investigated biochemical markers of bone turnover to detect possible sex differences.

METHODS

Patients (563; 75 men and 488 women) with osteoporosis were retrospectively investigated. All patients were administered with teriparatide at 20 μg/day for 12 months. The primary efficacy measure was changed in lumbar spine (LS) and femoral neck (FN) bone mineral density (BMD) after 12 months of treatment. The change in serum levels of procollagen type I N-terminal propeptide (PINP) and urinary N-telopeptide (uNTX) excretion after 4, 8 and 12 months of treatment were also measured.

RESULTS

In men, the percent LS BMD significantly increased by 11.3 ± 9.9 % (mean ± standard deviation (SD)) and the FN BMD increased by 0.4 ± 6.4 % without a significant difference at 12 months. In postmenopausal women, the percent LS BMD significantly increased by 9.6 ± 8.1 % and the FN BMD significantly increased by 2.4 ± 7.8 % at 12 months. The percent and absolute BMD increases in LS and FN between men and women were similar. The absolute increases in PINP were similar in both groups at 4, 8 and 12 months. However, the absolute increases in uNTX were significantly lower in men than in women at 8 and 12 months.

CONCLUSION

Daily teriparatide treatment was as effective in men as in postmenopausal women regardless of sex differences.

Bone-crack detection, targeting, and repair using ion gradients

Bone cracks can be detected by utilizing the damaged matrix itself as both the trigger and the fuel. A crack in a material with a high mineral content such as bone generates ion gradients, which can be utilized for active targeting and treatment. This approach to targeting a biological structure augments current methods, which are focused on biomacromolecular interactions involving proteins and nucleic acids.

Bisphosphonates and atrial fibrillation: Bayesian meta-analyses of randomized controlled trials and observational studies

Background

Occurrence of atrial fibrillation (AF) amongst bisphosphonate users has been increasingly reported but results are conflicting. We performed a Bayesian meta-analysis to address the possible association between the occurrence of AF and bisphosphonate use and estimated the posterior probability of development of AF with bisphosphonate use.

Methods

Randomized controlled trials (RCTs) evaluating the efficacy and safety of bisphosphonates for treating and preventing osteoporosis, and observational studies investigating the incidence of AF amongst bisphosphonate users, were searched in electronic databases. We pooled the effect size with Bayesian meta-analysis for odds ratio (OR) and calculated its posterior probability of development of AF in bisphosphonate users for RCTs and observational studies, reported with the 95% credible interval (CI).

Results

Of 1751 potentially relevant citations initially retrieved, 4 RCTs and 2 reports of RCTs, and 3 observational studies were included for this meta-analysis. On pooling the RCTs, there was a non-significantly higher risk of overall (OR 1.184, 95% CI 0.837-1.656) and serious AF (OR 1.590, 95% CI 0.613-3.751) in bisphosphonate-treated patients. Combining data of observational studies also revealed a non-significantly higher risk of AF in bisphosphonate users (OR 1.251, 95% CI 0.980-1.732). Using Bayesian meta-analysis based on the effect size of observational studies as the prior, the posterior probability of OR>1.2 in the development of AF amongst bisphosphonate users in the RCTs was 0.484. Egger's regression demonstrated no notable publication bias in all the analyses.

Conclusion

The current meta-analysis revealed no evidence of a higher risk of AF associated with bisphosphonate use. Nevertheless, based on Bayesian meta-analysis with the effect size of the observational studies as the prior, the posterior probabilities of development of AF was found to be 0.484 if the risk of AF was estimated to be more than 20%. The results of the current meta-analysis thus offer clinicians the practical probability of development of AF in patients who take bisphosphonates for the treatment of bone loss and corticosteroid induced osteoporosis.