Three-year denosumab treatment in postmenopausal Japanese women and men with osteoporosis: results from a 1-year open-label extension of the Denosumab Fracture Intervention Randomized Placebo Controlled Trial (DIRECT)

SUMMARY

A 12-month extension phase of DIRECT in Japanese subjects with osteoporosis showed that total 3 years of denosumab treatment in Japanese postmenopausal women and men with osteoporosis was associated with low fracture rates, persistent bone turnover marker (BTM) reductions, continuous bone mineral density (BMD) increases, and a favorable overall benefit/risk profile.

INTRODUCTION

The DIRECT trial demonstrated that 2 years of treatment with denosumab 60 mg subcutaneously every 6 months significantly reduced the incidence of vertebral fracture compared to placebo in Japanese postmenopausal women and men with osteoporosis. The purpose of this study is to evaluate the efficacy and safety of denosumab treatment for up to 3 years.

METHODS

This study includes a 2-year randomized, double-blind, placebo-controlled phase and a 1-year open-label extension phase in which all subjects received denosumab. The data correspond to 3 years of denosumab treatment in subjects who received denosumab (long-term group) and 1 year of denosumab treatment in subjects who received placebo (cross-over group) in the double-blind phase.

RESULTS

Eight hundred and ten subjects who completed the double-blind phase enrolled into the extension phase, and 775 subjects completed the study. All subjects received denosumab with daily supplements of calcium and vitamin D. The cumulative 36-month incidences of new or worsening vertebral fractures and new vertebral fractures were 3.8 and 2.5 %, respectively, in the long-term group. In this group, the BMD continued to increase, and the reduction in BTMs was maintained. In the cross-over group, comparable BMD increases and BTMs reductions to those of in their first year of the long-term group were confirmed. Adverse events did not show a notable increase with long-term denosumab administration. One event of osteonecrosis of the jaw occurred in the cross-over group.

CONCLUSIONS

Three-year denosumab treatment in Japanese subjects with osteoporosis showed a favorable benefit/risk profile.

Heterologous production, purification, and immunodetection of Magnaporthe oryzae avirulence protein AVR-Pia

The avirulence gene AVR-Pia of Magnaporthe oryzae, which induces a hypersensitive reaction in rice cultivars containing the resistance gene Pia, was expressed in Escherichia coli. AVR-Pia protein was collected as inclusion bodies, denatured, and refolded. Finally, recombinant AVR-Pia (rAVR-Pia) protein was purified by column chromatography. Infiltration of rAVR-Pia triggered cell browning in the leaves of rice cultivar Aichiasahi (Pia), with accumulation of H2O2 and induction of PR1a expression in rice. On the other hand, these reactions were not observed in Shin-2 (pia) leaves after the same treatment. This observation indicated that rAVR-Pia had the function of an avirulence protein. rAVR-Pia was used for immunization of a rabbit, and anti-AVR-Pia antiserum was prepared. The specificity of this antibody was appraised by detecting native AVR-Pia in the inoculated leaf sheath extract using Western blotting in combination with immunoprecipitation. Native AVR-Pia was successfully detected, and its molecular weight was estimated to be 7.4 kDa, indicating signal peptide cleavage. Additionally, secreted native AVR-Pia was quantified as 3.7 ng/g rice sheath.

The Molecular Phylogeny of the GenusRhizopusBased on rDNA Sequences

In order to establish the molecular phylogeny of the genus Rhizopus, three molecules of the ribosomal RNA-encoding DNA (rDNA), complete 18S, internal transcribed spacer (ITS)1-5.8S-ITS2, and 28S D1/D2 regions of all the species of the genus were sequenced. Phylogenetic trees showed three major clusters corresponding to the three groups in the current morphological taxonomy, microsporus-group, stolonifer-group, and R. oryzae. R. stolonifer var. lyococcos was clustered independently from the major clusters. R. schipperae clustered differently in all trees. Strains of R. sexualis had multiple ITS sequences. A. rouxii clustered with R. oryzae. These results indicate the possibility of molecular identification of species groups using rDNA sequencing. Reclassification of the genus might be appropriate.

Characterization of multi-antibiotic-resistant Escherichia coli Isolated from beef cattle in Japan

The emergence of multiple-antibiotic-resistance bacteria is increasing, which is a particular concern on livestock farms. We previously isolated 1,347 antimicrobial-resistant (AMR) Escherichia coli strains from the feces of beef cattle on 14 Japanese farms. In the present study, the genetic backgrounds and phylogenetic relationships of 45 AMR isolates were characterized by the chromosome phylotype, AMR phenotype, AMR genotype, and plasmid type. These isolates were classified into five chromosome phylotypes, which were closely linked to the farms from which they were isolated, suggesting that each farm had its own E. coli phylotype. AMR phenotype and plasmid type analyses yielded 8 and 14 types, all of which were associated with the chromosomal phylotype and, thus, to the original farms. AMR genotype analysis revealed more variety, with 16 types, indicating both inter- and intra-farm diversity. Different phylotype isolates from the same farm shared highly similar plasmid types, which indicated that plasmids with AMR genes could be transferred between phylotypes, thereby generating multi-antibiotic-resistant microorganisms. This ecological study demonstrated that the chromosome phylotype was strongly correlated with the farm from which they were isolated, while the AMR phenotype, genotype, and plasmid type were generally correlated with the chromosome phylotype and farm source.

The effects of once-weekly teriparatide on hip structure and biomechanical properties assessed by CT

SUMMARY

Once-weekly administration of 56.5 μg teriparatide improved cortical bone parameters and biomechanical parameters at the proximal femur by CT geometry analysis.

INTRODUCTION

The aim of this study was to evaluate the effects of weekly administration of teriparatide [human PTH (1-34)] on bone geometry, volumetric bone mineral density (vBMD), and parameters of bone strength at the proximal femur which were longitudinally investigated using computed tomography (CT).

METHODS

The subjects were a subgroup of a recent, randomly assigned, double-blind study (578 subjects) comparing the anti-fracture efficacy of a once-weekly subcutaneous injection of 56.5 μg teriparatide with placebo (TOWER trial).

RESULTS

Sixty-six ambulatory postmenopausal women with osteoporosis were enrolled at 15 study sites having multi-detector row CT, and included women injected with teriparatide (n = 29, 74.2 ± 5.1 years) or with placebo (n = 37, 74.8 ± 5.3 years). CT data were obtained at baseline and follow-up scans were performed at 48 and 72 weeks. The data were analyzed to obtain cross-sectional densitometric, geometric, and biomechanical parameters including the section modulus (SM) and buckling ratio (BR) of the femoral neck, inter-trochanter, and femoral shaft. We found that once-weekly teriparatide increased cortical thickness/cross-sectional area (CSA) and total area, and improved biomechanical properties (i.e., decreasing BR) at the femoral neck and shaft. Teriparatide did not change the cortical perimeter.

CONCLUSIONS

Our longitudinal analysis of proximal femur geometry by CT revealed that once-weekly administration of 56.5 μg teriparatide improved cortical bone parameters at the femoral neck and shaft and also improved biomechanical parameters.

Comparison of Yacon (Smallanthus sonchifolius) Tuber with Commercialized Fructo-oligosaccharides (FOS) in Terms of Physiology, Fermentation Products and Intestinal Microbial Communities in Rats

The yacon (Smallanthus sonchifolius) tuber was examined with regard to its prebiotic effects compared with commercialized fructo-oligosaccharides (FOS). A feed containing 10% yacon tuber, which is equivalent to 5% commercialized FOS in terms of the amount of fructo-oligosaccharides (GF2, GF3 and GF4), was administrated to rats for 28 days. The yacon diet changed the intestinal microbial communities beginning in the first week, resulting in a twofold greater concentration of cecal short-chain fatty acids (SCFAs). The SCFA composition differed, but the cecal pH in rats fed yacon tuber was equal to that in rats fed FOS. Serum triglycerides were lower in rats fed yacon compared with rats fed FOS and the control diet. Cecal size was greater with the yacon tuber diet compared with the control diet. The abundant fermentation in the intestines created a selective environment for the intestinal microbiota, which included Lactobacillus acidophilus, Bifidobacterium pseudolongum, Bifidobacterium animalis and Barnesiella spp. according to identification with culture-independent analysis, 16S rRNA gene PCR-DGGE combined with cloning and sequencing. Barnesiella spp. and B. pseudolongum were only found in the rats fed the yacon diet, while L. acidophilus and B. animalis were found in abundance in rats fed both the yacon and FOS diets. The genus Barnesiella has not previously been reported to be associated with yacon or FOS fermentation. We concluded that the physiological and microbiological effects of the yacon tuber were different from those of FOS. Differences in cecal size, blood triglycerides and microbial community profiles including their metabolites (SCFAs) between the yacon tuber and FOS were shown to be more greatly affected by the yacon tuber rather than FOS.

Homologous recombination causes the spontaneous deletion of AVR-Pia in Magnaporthe oryzae

AVR-Pia, an avirulence gene in the genome of the rice blast fungus Magnaporthe oryzae, triggers a hypersensitive reaction in rice cultivars harbouring the resistance gene Pia. The copy number of AVR-Pia was revealed to vary from one to three among M. oryzae isolates avirulent to Pia rice, and three copies of the gene were located on a single chromosome in strain Ina168, from which the gene was originally cloned. The spontaneous avr-Pia mutant originated from Ina168, named Ina168m95-1, which lacks the AVR-Pia gene, and was therefore used to elucidate the molecular mechanism of the deletion of all three copies of AVR-Pia. Screening and analysis of cosmid clones indicated that two copies of the DNA-type transposon Occan (Occan(9E12) and Occan(3A3) ) were located on the same chromosome, and three copies of AVR-Pia were located in between the two Occan elements. Ina168m95-1 contains a conserved Occan element, named Occan(m95-1) , between sequences homologous to the 5'-flanking region of Occan(3A3) and the 3'-flanking region of Occan(9E12) . In addition, sequence polymorphisms indicated a homologous recombination between Occan(3A3) and Occan(9E12) , which resulted in Occan(m95-1) . Based on these observations, we propose the hypothesis that homologous recombination in the two Occan elements leads to the deletion of AVR-Pia in Ina168m95-1.

Ocular volumetry using fast high-resolution MRI during visual fixation

BACKGROUND AND PURPOSE

Volumetry may be useful for evaluating treatment response and prognosis of intraocular lesions. Phantom, volunteer, and patient studies were performed to determine whether ocular MR volumetry is reproducible.

MATERIALS AND METHODS

Half-Fourier single-shot RARE and FSPGR sequences at 1.5T with a 76-mm-diameter surface coil were optimized to obtain still ocular images. Volumetry accuracies of each sequence were compared with simulated subretinal phantom volumes. Ocular volumetry was performed in 15 volunteers twice in 1 week by using contiguous axial images of the globes while the subjects stared at a target, and images were acquired in 2 seconds before the subjects were instructed to blink, with this process repeated as necessary. Imaging, intraobserver, and interobserver reproducibility for volumes of the whole eyeball and anterior chamber were assessed. Ocular volumetry was also performed in 6 patients with intraocular tumors before and after treatment.

RESULTS

The phantom study demonstrated that measurement error rates with RARE were significantly lower than with FSPGR (P<.01). The volunteer study demonstrated excellent imaging and intraobserver reproducibility of RARE volumetry for whole eyeballs and anterior chambers (P<.01). Although no interobserver differences were observed in anterior chamber volume measurement (P=.33), there was a significant difference between the 2 observers in eyeball volume measurement (P<.01). Follow-up volumetric data were useful for treatment decisions in all patients.

CONCLUSIONS

Ocular volumetry from contiguous ultrafast RARE images obtained during visual fixation is feasible in volunteer and patient studies and is superior to FSPGR images.

A multicenter randomized double-masked comparative study of different preparations of alendronate in osteoporosis - monthly (four weeks) intravenous versus once weekly oral administrations

OBJECTIVE

The aim of this study was to evaluate the efficacy and safety of intravenous alendronate (ALN) 900 µg every 4 weeks compared to oral ALN 35 mg once weekly.

METHODS

A 52-week, multicenter, randomized, double-masked, active-controlled, parallel-group, non-inferiority study was conducted in a total of 325 Japanese patients aged 48-87 years with osteoporosis. Patients were randomly assigned to an intravenous ALN (iv, n = 162) group or oral ALN (po, n = 163) group. The efficacy of the both formulations was assessed primarily by bone mineral density (BMD) measurement.

RESULTS

The percentage BMD change from baseline in lumbar spine (L2-L4) after 52 weeks of treatment was 6.4 ± 0.3% in the iv group and 6.0 ± 0.3% in the po group (least-squares mean ± SE). The inter-group difference in least-squares mean of percentage change from baseline in BMD was 0.37%, and its 95% confidence interval was -0.47% to 1.20%. The non-inferiority of the iv group was established against the po group with a prespecified non-inferiority margin (Δ) of 1.5%. In addition, the four bone turnover markers were reduced to a similar level by either treatment throughout the treatment period. The safety profile was also similar between the two treatment groups. Because of the limitations presented in this study, the results of the iv group may not apply to non-Japanese patients with osteoporosis.

CONCLUSIONS

The efficacy and safety of the intravenous ALN 900 µg once every 4 weeks were similar to those of the oral ALN 35 mg once weekly, indicating that intravenous administration of ALN is an effective treatment for osteoporosis and will provide a useful alternative to oral dosing.

Efficacy and safety of monthly oral minodronate in patients with involutional osteoporosis

Monthly minodronate at 30 or 50 mg had similar efficacy as 1 mg daily in terms of change in bone mineral density (BMD) and bone turnover markers with similar safety profiles. This new regimen provides patients with a new option for taking minodronate.

INTRODUCTION

Minodronate at a daily oral dose of 1 mg has been proven to have antivertebral fracture efficacy. In the present study, the efficacy and safety of oral minodronate at monthly doses of either 30 mg or 50 mg were compared with a daily dose of 1 mg.

METHODS

A total of 692 patients with involutional osteoporosis were randomized to receive minodronate at either 30 or 50 mg monthly or a daily dose of 1 mg. The primary endpoint was the percent change from baseline in lumbar spine (LS) BMD at 12 months. Total hip BMD, bone turnover markers, serum calcium (Ca), and parathyroid hormone (PTH) levels were also evaluated.

RESULTS

Minodronate at monthly doses of 30 or 50 mg were noninferior to the 1 mg daily dose in terms of change in LS-BMD. Changes in total hip BMD were also comparable. Although a transient decrease in serum Ca and increase in PTH levels were observed in all three groups at slightly different magnitudes and time courses, changes in bone turnover markers were comparable among the different dosage groups with a similar time course. Safety profiles were also comparable.

CONCLUSION

Minodronate at monthly doses of 30 or 50 mg has similar efficacy to the daily 1 mg dose in terms of BMD and bone turnover markers with similar tolerability.

A multifaceted genomics approach allows the isolation of the rice Pia-blast resistance gene consisting of two adjacent NBS-LRR protein genes

The Oryza sativa (rice) resistance gene Pia confers resistance to the blast fungus Magnaporthe oryzae carrying the AVR-Pia avirulence gene. To clone Pia, we employed a multifaceted genomics approach. First, we selected 12 R-gene analog (RGA) genes encoding nucleotide binding site-leucine rich repeats (NBS-LRRs) proteins from a region on chromosome 11 that shows linkage to Pia. By using seven rice accessions, we examined the association between Pia phenotypes and DNA polymorphisms in the 10 genes, which revealed three genes (Os11gRGA3-Os11gRGA5) exhibiting a perfect association with the Pia phenotypes. We also screened ethyl methane sulfonate (EMS)-treated mutant lines of the rice cultivar 'Sasanishiki' harboring Pia, and isolated two mutants that lost the Pia phenotype. DNA sequencing of Os11gRGA3-Os11gRGA5 from the two mutant lines identified independent mutations of major effects in Os11gRGA4. The wild-type 'Sasanishiki' allele of Os11gRGA4 (SasRGA4) complemented Pia function in both mutants, suggesting that SasRGA4 is necessary for Pia function. However, when the rice cultivar 'Himenomochi' lacking Pia was transfected with SasRGA4, the Pia phenotype was not recovered. An additional complementation study revealed that the two NBS-LRR-type R genes, SasRGA4 and SasRGA5, that are located next to each other and oriented in the opposite direction are necessary for Pia function. A population genetics analysis of SasRGA4 and SasRGA5 suggests that the two genes are under long-term balancing selection.

One of two major paralogs of AVR-Pita1 is functional in Japanese rice blast isolates

We analyzed the avirulence gene AVR-Pita1 in Japanese rice blast isolates to determine how they gain virulence toward rice cultivars containing the Pita resistance gene. An avirulent isolate, OS99-G-7a (G7a), from a Japanese commercial field contained two paralogs of AVR-Pita1, designated as AVR-Pita1(JA) and AVR-Pita1(JB). Analysis of virulent, independent mutants derived from G7a, a single avirulent progenitor strain, indicated that AVR-Pita1(JA) was functional but AVR-Pita1(JB) was nonfunctional. The most frequent mutation was loss of AVR-Pita1(JA). Analyses of field isolates collected from diverse areas in Japan revealed that most of the AVR-Pita1 genes carried by Japanese isolates were identical to AVR-Pita1(JA) or AVR-Pita1(JB). The relationship between these major paralogs in Japanese isolates and the virulence of the strains carrying them indicate that AVR-Pita1(JA) is functional but AVR-Pita1(JB) is not, as is the case in G7a. Isolates that show virulence toward rice cultivars containing the Pita gene are presumed to have evolved virulence from avirulent origins via loss of AVR-Pita1(JA), except for one case in which virulence resulted from a base substitution. In this study, we discuss the properties and specificities of Japanese rice blasts that relate to virulence against Pita-containing rice. Furthermore, we present a method to amplify AVR-Pita1(JA) and AVR-Pita1(JB) separately and, specifically, to monitor functional AVR-Pita1 in Japan.