Preventative effects of 1-methyl-1,2,3,4-tetrahydroisoquinoline derivatives (N-functional group loading) on MPTP-induced parkinsonism in mice.

1,2,3,4-tetrahydroisoquinoline (TIQ) is endogenously present in the human brain, and some of its derivatives are thought to contribute to the induction of Parkinson's disease (PD)-like signs in rodents and primates. In contrast, the endogenous TIQ derivative 1-methyl-TIQ (1-MeTIQ) is reported to be neuroprotective. In the present study, we compared the effects of artificially modified 1-MeTIQ derivatives (loading an N-propyl, N-propenyl, N-propargyl, or N-butynyl group) on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD-like signs in mice. In a behavioral study, MPTP-induced bradykinesia was significantly decreased by all compounds. However, only 1-Me-N-propargyl-TIQ showed an inhibitory effect by blocking the MPTP-induced reduction in striatal dopamine content and the number of nigral tyrosine hydroxylase-positive cells. Western blot analysis showed that 1-Me-N-propargyl-TIQ and 1-Me-N-butynyl-TIQ potently prevented the MPTP-induced decrease in dopamine transporter expression, whereas 1-MeTIQ and 1-Me-N-propyl-TIQ did not. These results suggest that although loading an N-propargyl group on 1-MeTIQ clearly enhanced neuroprotective effects, other N-functional groups showed distinct pharmacological properties characteristic of their functional groups. Thus, the number of bonds and length of the N-functional group may contribute to the observed differences in effect.

Vincristine increased spinal cord substance P levels in a peripheral neuropathy rat model.

Chemotherapy-induced peripheral neuropathy has an important impact on the quality of life of cancer patients. Vincristine-induced neuropathy is a major dose-limiting side effect. Symptoms of peripheral neuropathy are spontaneous pain, allodynia, and hyperalgesia. To analyze the contribution of substance P to the development of vincristine-induced mechanical allodynia/hyperalgesia, substance P levels in the rat spinal dorsal horn were analyzed after vincristine treatment. Mechanical allodynia/hyperalgesia was tested with the von Frey filaments 14 days after intraperitoneal (i.p.) administration of vincristine 0.1 mg/kg/day in rats. Vincristine-induced mechanical allodynia/hyperalgesia after day 14 was significantly inhibited by the neurokinin 1 receptor antagonist, aprepitant (20 mg/kg, s.c.). Immunohistochemistry showed that vincristine treatment significantly increased substance P expression (30.3% ± 2.4%) compared to saline treatment in the superficial layers of the spinal dorsal horn. Moreover, vincristine treatment significantly increased the substance P level in the spinal cord. These results suggest that vincristine treatment increases substance P in the spinal dorsal horn, and that aprepitant attenuates mechanical allodynia/hyperalgesia in vincristine-induced neuropathic rats.

Blood Pressure Level and Variability During Long-Term Prasugrel or Clopidogrel Medication After Stroke: PRASTRO-I.

BACKGROUND AND PURPOSE: High blood pressure increases bleeding risk during treatment with antithrombotic medication. The association between blood pressure levels and the risk of recurrent stroke during long-term secondary stroke prevention with thienopyridines (particularly prasugrel) has not been well studied. METHODS: This was a post hoc analysis of the randomized, double-blind, multicenter PRASTRO-I trial (Comparison of Prasugrel and Clopidogrel in Japanese Patients With Ischemic Stroke-I). Patients with noncardioembolic stroke were randomly assigned (1:1) to receive prasugrel 3.75 mg/day or clopidogrel 75 mg/day for 96 to 104 weeks. Risks of any ischemic or hemorrhagic stroke, combined ischemic events, and combined bleeding events were determined based on the mean level and visit-to-visit variability, including successive variation, of systolic blood pressure (SBP) throughout the observational period. These risks were also compared between quartiles of mean SBP level and successive variation of SBP. RESULTS: A total of 3747 patients (age 62.1±8.5 years, 797 women), with a median average SBP level during the observational period of 132.5 mm Hg, were studied. All the risks of any stroke (146 events; hazard ratio, 1.318 [95% CI, 1.094-1.583] per 10-mm Hg increase), ischemic stroke (133 events, 1.219 [1.010-1.466]), hemorrhagic stroke (13 events, 3.247 [1.660-6.296]), ischemic events (142 events, 1.219 [1.020-1.466]), and bleeding events (47 events, 1.629 [1.172-2.261]) correlated with increasing mean SBP overall. Similarly, an increased risk of these events correlated with increasing successive variation of SBP (hazard ratio, 3.078 [95% CI, 2.220-4.225] per 10-mm Hg increase; 3.051 [2.179-4.262]; 3.276 [1.172-9.092]; 2.865 [2.042-4.011]; 2.764 [1.524-5.016], respectively). Event rates did not differ between the clopidogrel and prasugrel groups within each quartile of SBP or successive variation of SBP. CONCLUSIONS: Both high mean SBP level and high visit-to-visit variability in SBP were significantly associated with the risk of recurrent stroke during long-term medication with either prasugrel or clopidogrel after stroke. Control of hypertension would be important regardless of the type of antiplatelet drugs. Registration: URL: https://www.clinicaltrials.jp; Unique identifier: JapicCTI-111582.

Safety and Efficacy of Prasugrel in Elderly/Low Body Weight Japanese Patients with Ischemic Stroke: Randomized PRASTRO-II.

INTRODUCTION: The safety of prasugrel in elderly and/or low body weight Japanese patients with ischemic stroke who have a relatively high bleeding risk with antiplatelet therapy remains unknown. OBJECTIVE: We aimed to investigate the safety and efficacy of long-term prasugrel monotherapy for stroke prevention compared with clopidogrel in elderly and/or low body weight Japanese patients with non-cardioembolic ischemic stroke. METHODS: In this randomized, double-blind, comparative, phase III study, elderly (age ≥75 years) and/or low body weight (≤50 kg) Japanese patients with a previous history of non-cardioembolic ischemic stroke were assigned to a prasugrel 3.75 mg (PRA3.75) group, a prasugrel 2.5 mg (PRA2.5) group, or a clopidogrel 50 mg (CLO50) group and followed up for 48 weeks. The primary safety endpoint was the combined incidence of primary safety events, defined as life-threatening, major, and other clinically relevant bleeding. The efficacy endpoint was a composite of ischemic stroke, myocardial infarction, and death from other vascular causes. RESULTS: A total of 654 patients (age 76.4 ± 7.3 years, body weight 55.6 ± 9.3 kg, women 43.9%) from 74 medical institutions within Japan were enrolled. The combined incidence (95% CI) of primary safety events was 4.2% (1.9-7.8%), 1.9% (0.5-4.7%), and 3.6% (1.6-6.9%) in the PRA3.75 group (n = 216), PRA2.5 group (n = 215), and CLO50 group (n = 223), respectively (hazard ratios [HR] PRA3.75/CLO50, 1.13 [0.44-2.93]; PRA2.5/CLO50, 0.51 [0.15-1.69]). The incidences of bleeding leading to treatment discontinuation (95% CI) were 2.3% (0.8-5.3%), 0.9% (0.1-3.3%), and 2.2% (0.7-5.2%) in the PRA3.75, PRA2.5, and CLO50 groups, respectively (HRs PRA3.75/CLO50, 1.01 [0.29-3.48]; PRA2.5/CLO50, 0.41 [0.08-2.12]). There was no significant difference in all bleeding events between groups. The incidence of ischemic stroke, myocardial infarction, and death from other vascular causes was lower, but not significantly so, in patients treated with prasugrel than in patients treated with clopidogrel: PRA3.75, 0.0% (0/216); PRA2.5, 3.3% (7/215); and CLO50, 3.6% (8/223; HRs PRA3.75/CLO50, 0.00 [0.00-0.00]; PRA2.5/CLO50, 0.90 [0.32-2.47]). CONCLUSIONS: Elderly and/or low body weight -Japanese patients with previous non-cardioembolic ischemic stroke who received PRA3.75 showed similar results in terms of primary safety endpoint, and a numerically lower incidence of ischemic stroke, myocardial infarction, and death from other vascular causes, compared with those who received CLO50.

Pharmacodynamic assessment of prasugrel and clopidogrel in patients with non-cardioembolic stroke: a multicenter, randomized, active-control clinical trial.

Prasugrel, a novel P2Y12 receptor antagonist, has been shown to be more effective than clopidogrel for preventing cardiovascular events in patients with acute coronary syndromes undergoing percutaneous coronary intervention. We investigated the dose-response antiplatelet effects of prasugrel compared with clopidogrel in Japanese patients with non-cardioembolic stroke. The influence of cytochrome P450 (CYP) polymorphisms on the antiplatelet effects of both drugs was also compared. In this multicenter randomized active-control comparative study, patients were randomized to receive prasugrel 2.5 mg, 5 mg, or 7.5 mg (double blind) or clopidogrel 75 mg (open label) once daily for 14 days. The primary endpoint was inhibition of platelet aggregation (IPA) in response to adenosine diphosphate 20 µM within 8 h of study drug administration on day 14. Of the 66 patients randomized, data from 63 (prasugrel 2.5 mg, 5 mg, and 7.5 mg groups, n = 14, 16, and 18, respectively; clopidogrel group, n = 15) were used in the pharmacodynamic assessment. IPA (arithmetic mean ± SD) after prasugrel administration increased dose-dependently (33 ± 9%, 44 ± 11%, and 53 ± 14%, at 2.5 mg, 5 mg, and 7.5 mg, respectively) and was higher in these groups than after clopidogrel (23 ± 16%). In a subgroup of CYP2C19 intermediate metabolizers, IPA was higher in the prasugrel 5 mg and 7.5 mg groups than in the clopidogrel group. No death or serious adverse events were reported. Prasugrel was well tolerated at doses up to 7.5 mg/day and had antiplatelet effects higher than those of clopidogrel 75 mg/day. CYP2C19 polymorphisms may have reduced clopidogrel-induced IPA.

Paclitaxel Induces Upregulation of Transient Receptor Potential Vanilloid 1 Expression in the Rat Spinal Cord.

Painful peripheral neuropathy is a common adverse effect of paclitaxel (PTX) treatment. To analyze the contribution of transient receptor potential vanilloid 1 (TRPV1) in the development of PTX-induced mechanical allodynia/hyperalgesia and thermal hyperalgesia, TRPV1 expression in the rat spinal cord was analyzed after intraperitoneal administration of 2 and 4 mg/kg PTX. PTX treatment increased the expression of TRPV1 protein in the spinal cord. Immunohistochemistry showed that PTX (4 mg/kg) treatment increased TRPV1 protein expression in the superficial layers of the spinal dorsal horn 14 days after treatment. Behavioral assessment using the paw withdrawal response showed that PTX-induced mechanical allodynia/hyperalgesia and thermal hyperalgesia after 14 days was significantly inhibited by oral or intrathecal administration of the TRPV1 antagonist AMG9810. We found that intrathecal administration of small interfering RNA (siRNA) to knock down TRPV1 protein expression in the spinal cord significantly decreased PTX-induced mechanical allodynia/hyperalgesia and thermal hyperalgesia. Together, these results demonstrate that TRPV1 receptor expression in spinal cord contributes, at least in part, to the development of PTX-induced painful peripheral neuropathy. TRPV1 receptor antagonists may be useful in the prevention and treatment of PTX-induced peripheral neuropathic pain.

Influence of cytochrome P450 polymorphisms on the antiplatelet effects of prasugrel in patients with non-cardioembolic stroke previously treated with clopidogrel.

This randomized double-blind crossover study aimed to investigate the influence of cytochrome P450 (CYP) 2C19 polymorphisms on the antiplatelet effects of prasugrel in patients with non-cardioembolic stroke treated with clopidogrel. Patients received clopidogrel 75 mg/day for > 4 weeks. Subsequently, patients received prasugrel 3.75 mg/day (group A; n = 64) or 2.5 mg/day (group B; n = 65) for 4 weeks followed by a 4 week switched-dose regimen. To assess the influence of CYP2C19 polymorphisms, patients were classified as extensive metabolizers (EMs), intermediate metabolizers (IMs), and poor metabolizers (PMs). The primary endpoint was P2Y12 reaction units (PRU) at the end of each 4 week treatment. A significant reduction in PRU was noted after treatment with prasugrel 3.75 mg/day compared with the pre-dose value (after treatment with clopidogrel) (p < 0.0001). By CYP2C19 phenotypes, a significant reduction in PRU was noted in IMs and PMs after treatment with prasugrel 3.75 mg/day and in PMs after treatment with prasugrel 2.5 mg/day, as compared with the pre-dose value (p < 0.0001). The plasma concentration of the active metabolite of clopidogrel was relatively low in PMs compared to EMs and IMs; prasugrel was similar across all CYP2C19 phenotypes. No major or clinically significant hemorrhagic adverse events occurred. By CYP2C19 phenotype, the antiplatelet effects of prasugrel were greater with 3.75 mg/day in IMs and PMs, and with 2.5 mg/day in PMs compared with clopidogrel 75 mg/day, without safety concerns. CYP2C19 polymorphisms did not affect the plasma concentration of the active metabolite of prasugrel or its antiplatelet effects. (JapicCTI-101044).

Edoxaban for the management of elderly Japanese patients with atrial fibrillation ineligible for standard oral anticoagulant therapies: Rationale and design of the ELDERCARE-AF study.

Edoxaban-a non-vitamin K antagonist oral anticoagulant (NOAC)- 60-mg and 30-mg once-daily dose regimens are noninferior versus well-managed warfarin for the prevention of stroke or systemic embolic events (SEE) with less major bleeding in patients with nonvalvular atrial fibrillation (NVAF). There are no published data from phase 3 clinical trials specifically evaluating the use of NOACs in elderly NVAF patients, especially those considered ineligible for available oral anticoagulants. The Edoxaban Low-Dose for EldeR CARE AF patients (ELDERCARE-AF) study is a phase 3, randomized, double-blind, placebo-controlled, parallel-group, multicenter study that will compare the safety and efficacy of once-daily edoxaban 15 mg versus placebo in Japanese patients with NVAF ≥80 years of age who are considered ineligible for standard oral anticoagulant therapy. A total of 800 patients (400 in each treatment group) are planned for randomization (1:1) to either edoxaban or placebo using a stratified randomization method with CHADS2 index score (2 points, ≥3 points) as a factor. The primary efficacy end point is the time to first onset of stroke or SEE. The net clinical outcome is the composite of stroke, SEE, major bleeding, and all-cause mortality. The primary safety end point is the incidence of major bleeding. The treatment period will continue until 65 patients with the primary efficacy events (ie, stroke or SEE) have been observed (2- to 2.5-year expected mean treatment period). The results of ELDERCARE-AF may provide clarity as to the efficacy and safety of edoxaban for the prevention of stroke or SEE in this high-risk population.

Vincristine-induced peripheral neuropathic pain and expression of transient receptor potential vanilloid 1 in rat.

The clinical anti-cancer efficacy of vincristine is limited by the development of dose-dependent peripheral neuropathy. Up-regulation of transient receptor potential vanilloid 1 (TRPV1) is correlated with peripheral neuropathy following anti-cancer drug treatment. To analyze the contribution of TRPV1 to the development of vincristine-induced mechanical allodynia/hyperalgesia, TRPV1 expression in the rat dorsal root ganglion (DRG) was analyzed after vincristine treatment. Mechanical allodynia/hyperalgesia was tested with von Frey filaments 14 days after intraperitoneal administration of 0.1 mg/kg vincristine in rats. TRPV1 expression in DRGs following vincristine treatment was assessed with western blot analysis and in situ hybridization histochemistry. Vincristine-induced mechanical allodynia/hyperalgesia after day 14 was significantly inhibited by the TRP antagonist ruthenium red (3 mg/kg, s.c.) and the TRPV1 antagonist capsazepine (30 mg/kg, s.c.). Vincristine treatment increased the expression of TRPV1 protein in DRG neurons. In situ hybridization histochemistry revealed that most of the TRPV1 mRNA-labeled neurons in the DRG were small in size. Immunohistochemistry showed that isolectin B4-positive small DRG neurons co-expressed TRPV1 protein 14 days after treatment. These results suggest that vincristine treatment increases TRPV1 expression in small DRG neurons. TRPV1 expression may contribute to the development of vincristine-induced painful peripheral neuropathy.

Engineering of Escherichia coli to facilitate efficient utilization of isomaltose and panose in industrial glucose feedstock.

Industrial glucose feedstock prepared by enzymatic digestion of starch typically contains significant amounts of disaccharides such as maltose and isomaltose and trisaccharides such as maltotriose and panose. Maltose and maltosaccharides can be utilized in Escherichia coli fermentation using industrial glucose feedstock because there is an intrinsic assimilation pathway for these sugars. However, saccharides that contain α-1,6 bonds, such as isomaltose and panose, are still present after fermentation because there is no metabolic pathway for these sugars. To facilitate more efficient utilization of glucose feedstock, we introduced glvA, which encodes phospho-α-glucosidase, and glvC, which encodes a subunit of the phosphoenolpyruvate-dependent maltose phosphotransferase system (PTS) of Bacillus subtilis, into E. coli. The heterologous expression of glvA and glvC conferred upon the recombinant the ability to assimilate isomaltose and panose. The recombinant E. coli assimilated not only other disaccharides but also trisaccharides, including alcohol forms of these saccharides, such as isomaltitol. To the best of our knowledge, this is the first report to show the involvement of the microbial PTS in the assimilation of trisaccharides. Furthermore, we demonstrated that an L-lysine-producing E. coli harboring glvA and glvC converted isomaltose and panose to L-lysine efficiently. These findings are expected to be beneficial for industrial fermentation.

Serum folate receptor alpha as a biomarker for ovarian cancer: Implications for diagnosis, prognosis and predicting its local tumor expression.

Folate receptor alpha (FRA) is a GPI-anchored glycoprotein and encoded by the FOLR1 gene. High expression of FRA is observed in specific malignant tumors of epithelial origin, including ovarian cancer, but exhibits very limited normal tissue expression, making it as an attractive target for the ovarian cancer therapy. FRA is known to shed from the cell surface into the circulation which allows for its measurement in the serum of patients. Recently, methods to detect the soluble form of FRA have been developed and serum FRA (sFRA) is considered a highly promising biomarker for ovarian cancer. We prospectively investigated the levels of sFRA in patients clinically suspected of having malignant ovarian tumors. A total of 231 patients were enrolled in this study and analyzed for sFRA as well as tumor expression of FRA by immunohistochemistry. High sFRA was predominantly observed in epithelial ovarian cancer patients, but not in patients with benign or borderline gynecological disease or metastatic ovarian tumors from advanced colorectal cancers. Levels of sFRA were highly correlated to clinical stage, tumor grade and histological type and demonstrated superior accuracy for the detection of ovarian cancer than did serum CA125. High sFRA was significantly associated with shorter progression-free survival in both early and advanced ovarian cancer patients. Finally, tumor FRA expression status was strongly correlated with sFRA levels. Taken together, these data suggest that sFRA might be a useful noninvasive serum biomarkers for future clinical trials assessing FRA-targeted therapy.

Edoxaban vs. Warfarin in East Asian Patients With Atrial Fibrillation　- An ENGAGE AF-TIMI 48 Subanalysis.

BACKGROUND: In the multinational, double-blind, double-dummy ENGAGE AF-TIMI 48 phase 3 study, once-daily edoxaban was non-inferior to warfarin for prevention of stroke or systemic embolism event (SEE) in patients with non-valvular atrial fibrillation (AF). Here, we evaluated the efficacy and safety of edoxaban in patients from East Asia. METHODS AND RESULTS: Patients aged ≥21 years with documented AF and CHADS score ≥2 were randomized to receive once-daily edoxaban higher-dose (60 mg) or lower-dose (30 mg) regimen or warfarin dose-adjusted to an international normalized ratio of 2.0-3.0. Patients with a creatinine clearance of 30-50 ml/min, weighing ≤60 kg, or receiving strong p-glycoprotein inhibitors at randomization or during the study received a 50% dose reduction of edoxaban or matched placebo. This prespecified subanalysis included 1,943 patients from Japan, China, Taiwan, and South Korea. The annualized rate of stroke/SEE for higher-dose edoxaban was 1.34% vs. 2.62% for warfarin (hazard ratio [HR], 0.53; 95% confidence interval [CI]: 0.31-0.90, P=0.02) and 2.52% for lower-dose edoxaban (HR, 0.98; 95% CI: 0.63-1.54, P=0.93). Compared with warfarin (4.80%), major bleeding was significantly reduced for the higher-dose (2.86%; HR, 0.61; 95% CI: 0.41-0.89, P=0.011) and lower-dose regimens (1.59%; HR, 0.34; 95% CI: 0.21-0.54, P<0.001). CONCLUSIONS: Once-daily edoxaban provided similar efficacy to warfarin while reducing major bleeding risk in the East Asian population.

Oxaliplatin administration increases expression of the voltage-dependent calcium channel α2δ-1 subunit in the rat spinal cord.

Oxaliplatin is a chemotherapeutic agent that is effective against various types of cancer including colorectal cancer. Acute cold hyperalgesia is a serious side effect of oxaliplatin treatment. Although the therapeutic drug pregabalin is beneficial for preventing peripheral neuropathic pain by targeting the voltage-dependent calcium channel α2δ-1 (Cavα2δ-1) subunit, the effect of oxaliplatin-induced acute cold hypersensitivity is uncertain. To analyze the contribution of the Cavα2δ-1 subunit to the development of oxaliplatin-induced acute cold hypersensitivity, Cavα2δ-1 subunit expression in the rat spinal cord was analyzed after oxaliplatin treatment. Behavioral assessment using the acetone spray test showed that 6 mg/kg oxaliplatin-induced cold hypersensitivity 2 and 4 days later. Oxaliplatin-induced acute cold hypersensitivity 4 days after treatment was significantly inhibited by pregabalin (50 mg/kg, p.o.). Oxaliplatin (6 mg/kg, i.p.) treatment increased the expression level of Cavα2δ-1 subunit mRNA and protein in the spinal cord 2 and 4 days after treatment. Immunohistochemistry showed that oxaliplatin increased Cavα2δ-1 subunit protein expression in superficial layers of the spinal dorsal horn 2 and 4 days after treatment. These results suggest that oxaliplatin treatment increases Cavα2δ-1 subunit expression in the superficial layers of the spinal cord and may contribute to functional peripheral acute cold hypersensitivity.

Clinical benefit of graduated compression stockings for prevention of venous thromboembolism after total knee arthroplasty: post hoc analysis of a phase 3 clinical study of edoxaban.

BACKGROUND: Guidelines from the Japanese Circulation Society recommend prophylaxis with anticoagulation plus intermittent pneumatic compression or graduated compression stockings (GCS) among patients at the highest risk for developing venous thromboembolism (VTE). However, the benefits of concomitant GCS use for patients undergoing total knee arthroplasty (TKA) and receiving anticoagulation remain unknown. In this study, the efficacy of GCS plus anticoagulation compared with anticoagulation alone was evaluated among patients undergoing TKA. METHODS: This study is a post hoc analysis of a previously reported phase 3 trial involving patients undergoing TKA. In the primary study, which permitted the use of GCS for mechanical prophylaxis, patients were randomized to receive edoxaban 30 mg once daily or enoxaparin 20 mg twice daily for 11 to 14 days following TKA. The primary endpoint was the incidence of VTE, a composite of symptomatic deep vein thrombosis (DVT), symptomatic pulmonary embolism (PE), and asymptomatic DVT. Treatment comparisons were performed using the chi-square test, and the 95 % confidence intervals were calculated. RESULTS: Among patients receiving edoxaban, the incidence of VTE was 3.8 and 5.8 % for patients with and without GCS, respectively. For patients receiving enoxaparin, VTE incidence was 8.4 and 20.8 % among those with and without GCS, respectively. Overall, VTE incidence was 6.0 and 13.0 % for anticoagulated patients with and without GCS mechanical prophylaxis, respectively. No deaths or symptomatic PE were reported during this study. CONCLUSIONS: Although the incidence of VTE was >2-fold lower among patients receiving anticoagulation plus GCS compared with those receiving anticoagulation alone, statistical significance was not achieved. Further studies are required to confirm the findings of this preliminary analysis. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01181102.

Edoxaban versus enoxaparin for the prevention of venous thromboembolism after total knee or hip arthroplasty: pooled analysis of coagulation biomarkers and primary efficacy and safety endpoints from two phase 3 trials.

BACKGROUND: The objective of this analysis was to assess the effects of edoxaban compared with enoxaparin on key coagulation biomarkers and present pooled primary efficacy and safety results from phase 3 STARS E-3 and STARS J-V trials for prevention of venous thromboembolism (VTE) after total knee arthroplasty (TKA) or total hip arthroplasty (THA). METHODS: In the randomized, double-blind, double-dummy, multicenter, STARS E-3 and STARS J-V trials, patients received edoxaban 30 mg or enoxaparin 2000 IU (20 mg) twice daily for 11 to 14 days. The studies were conducted in Japan and Taiwan; enoxaparin dosing was based on Japanese label recommendations. The primary efficacy endpoint was incidence of VTE; the safety endpoint was major or clinically relevant nonmajor (CRNM) bleeding. Blood samples were taken at presurgical evaluation, pretreatment (postsurgery), predose on day 7, predose on completion of treatment, and at a follow-up examination 25 to 35 days after the last dose of study drug for D-dimer, prothrombin fragment 1 + 2 (F1+2), and soluble fibrin monomer complex (SFMC) measurement. RESULTS: A total of 716 patients enrolled in STARS E-3 and 610 patients enrolled in STARS J-V; 1326 patients overall. This analysis included 657 patients who received edoxaban 30 mg QD and 650 patients who received enoxaparin 20 mg BID. Incidence of VTE was 5.1 and 10.7% for edoxaban and enoxaparin, respectively (P <0.001). Incidence of combined major and CRNM bleeding was 4.6 and 3.7% for edoxaban and enoxaparin, respectively (P = 0.427). On day 7, mean D-dimer (4.4 vs 5.5 µg/mL), F1+2 (363 vs 463 pmol/L), and SFMC (5.7 vs 6.8 µg/mL) were lower in edoxaban-treated patients relative to enoxaparin-treated patients, respectively (P <0.0001 for all). At end of treatment, mean D-dimer (5.4 vs 6.2 µg/mL), F1+2 (292 vs 380 pmol/L), and SFMC (6.2 vs 7.2 µg/mL) were lower in edoxaban-treated patients relative to enoxaparin-treated patients (P <0.0001 for all). CONCLUSIONS: Edoxaban was superior to enoxaparin in prevention of VTE following TKA and THA, with comparable rates of bleeding events. Relative to enoxaparin, edoxaban significantly reduced D-dimer, F1+2, and SFMC. TRIAL REGISTRATION: Clintrials.gov NCT01181102 and NCT01181167. Both registered 8/12/2010.

Transient receptor potential ankyrin 1 that is induced in dorsal root ganglion neurons contributes to acute cold hypersensitivity after oxaliplatin administration.

BACKGROUND: Peripheral cold neuropathic pain is a serious side effect of oxaliplatin treatment. However, the mechanism of oxaliplatin-induced cold hyperalgesia is unknown. In the present study, we investigated the effects of oxaliplatin on transient receptor potential ankyrin 1 (TRPA1) in dorsal root ganglion (DRG) neurons of rats. RESULTS: Behavioral assessment using the acetone spray test showed that 3 and 6 mg/kg oxaliplatin (i.p.) induced acute cold hypersensitivity after 1, 2, 4, and 7 days. Real-time PCR showed that oxaliplatin (6 mg/kg) significantly increased TRPA1 mRNA expression in DRGs at days 1, 2, and 4. Western blotting revealed that oxaliplatin significantly increased TRPA1 protein expression in DRGs at days 2, 4, and 7. Moreover, in situ hybridization histochemistry revealed that most TRPA1 mRNA-labeled neurons in the DRGs were small in size. Oxaliplatin significantly increased co-localization of TRPA1 expression and isolectin B4 binding in DRG neurons. Oxaliplatin induced a significant increase in the percent of TRPA1 mRNA-positive small neurons in DRGs at days 1, 2, and 4. In addition, we found that intrathecal administration of TRPA1 antisense, but not TRPA1 mismatched oligodeoxynucleotides, knocked down TRPA1 expression and decreased oxaliplatin-induced cold hyperalgesia. Double labeling showed that p-p38 mitogen-activated protein kinase (MAPK) was co-expressed in TRPA1 mRNA-labeled neurons at day 2 after oxaliplatin administration. Intrathecal administration of the p38 MAPK inhibitor, SB203580, significantly decreased oxaliplatin-induced acute cold hypersensitivity. CONCLUSIONS: Together, these results demonstrate that TRPA1 expression via activation of p38 MAPK in DRG neurons, at least in part, contributes to the development of oxaliplatin-induced acute cold hyperalgesia.

Support of the infectivity of hepatitis delta virus particles by the envelope proteins of different genotypes of hepatitis B virus.

UNLABELLED: This study examined how the envelope proteins of 25 variants of hepatitis B virus (HBV) genotypes A to I support hepatitis delta virus (HDV) infectivity. The assembled virions bore the same HDV ribonucleoprotein and differed only by the HBV variant-specific envelope proteins coating the particles. The total HDV yields varied within a 122-fold range. A residue Y (position 374) in the HDV binding site was identified as critical for HDV assembly. Virions that bound antibodies, which recognize the region that includes the HBV matrix domain and predominantly but not exclusively immunoprecipitate the PreS1-containing virions, were termed PreS1*-HDVs. Using in vitro infection of primary human hepatocytes (PHH), we measured the specific infectivity (SI), which is the number of HDV genomes/cell produced by infection and normalized by the PreS1*-MOI, which is the multiplicity of infection that reflects the number of PreS1*-HDVs per cell in the inoculum used. The SI values varied within a 160-fold range and indicated a probable HBV genotype-specific trend of D > B > E > A in supporting HDV infectivity. Three variants, of genotypes B, C, and D, supported the highest SI values. We also determined the normalized index (NI) of infected PHH, which is the percentage of HDV-infected hepatocytes normalized by the PreS1*-MOI. Comparison of the SI and NI values revealed that, while a particular HBV variant may facilitate the infection of a relatively significant fraction of PHH, it may not always result in a considerable number of genomes that initiated replication after entry. The potential implications of these findings are discussed in the context of the mechanism of attachment/entry of HBV and HDV. IMPORTANCE: The study advances the understanding of the mechanisms of (i) attachment and entry of HDV and HBV and (ii) transmission of HDV infection/disease.

Short-Term Safety and Plasma Concentrations of Edoxaban in Japanese Patients With Non-Valvular Atrial Fibrillation and Severe Renal Impairment.

BACKGROUND: The short-term safety and plasma concentrations of edoxaban 15 mg once daily in Japanese patients with non-valvular atrial fibrillation (NVAF) and severe renal impairment (SRI; creatinine clearance [CLCR] ≥15 to <30 ml/min) were compared with those in NVAF patients with normal renal function or mild renal impairment (normal/MiRI; CLCR≥50 ml/min) treated with edoxaban 30 or 60 mg. METHODS AND RESULTS: In this Phase 3 multicenter open-label 3 parallel-group study, SRI patients received once-daily edoxaban 15 mg (n=50), whereas normal/MiRI patients were randomized to receive either once-daily edoxaban 30 or 60 mg (n=22 and 21, respectively) for 12 weeks. Plasma edoxaban concentrations and biomarkers of blood coagulation and fibrinolysis were measured. Adverse events and thromboembolic events were recorded throughout the study. Rates of any bleeding were comparable between SRI patients receiving edoxaban 15 mg (20.0%) and normal/MiRI patients receiving edoxaban 30 or 60 mg (22.7% and 23.8%, respectively). No major bleeding or thromboembolic events occurred in any treatment group. Similar plasma concentrations and biomarker profiles were observed in SRI patients receiving edoxaban 15 mg and normal/MiRI patients receiving edoxaban 30 or 60 mg. CONCLUSIONS: In this 12-week short-term study in Japanese NVAF patients with SRI, edoxaban 15 mg once daily exhibited similar safety, plasma concentration, and biomarker profiles as did the 30-mg and 60-mg doses in patients with normal/MiRI.

Effects of Regional Differences in Asia on Efficacy and Safety of Edoxaban Compared With Warfarin--Insights From the ENGAGE AF-TIMI 48 Trial.

BACKGROUND: In 21,105 patients with atrial fibrillation in the ENGAGE AF-TIMI 48 trial, edoxaban was non-inferior to warfarin in preventing thromboembolic events while reducing bleeding. We compared results in Japan with the rest of East Asia (EA), including China, Korea, and Taiwan. METHODS AND RESULTS: We compared baseline characteristics, time-in-therapeutic range (TTR) for warfarin, and outcomes (efficacy: stroke or systemic embolic events [SEE], safety: major bleeding). Interaction P values were used to assess for effect modification of treatment (higher-dose edoxaban [HDE, 60 mg/30 mg] vs. warfarin; lower-dose edoxaban [LDE, 30 mg/15 mg] vs. warfarin) by region with adjustments for baseline characteristics. Fewer patients in Japan (n=1,010) were female, taking aspirin or amiodarone, naïve to warfarin (P<0.001 for each), had a history of stroke or transient ischemic attack (P=0.02), and more patients needed dose reduction (P<0.001) compared with EA (n=933). The mean TTR was higher in Japan (70% vs. 56%, P<0.001). Evidence for statistical interactions was observed for HDE vs. warfarin by region for stroke/SEE (adjusted P-int=0.052) and major bleeding (adjusted P-int=0.048) with greater relative efficacy and safety with HDE in EA compared with Japan. No interactions were observed for LDE vs. warfarin after adjustment. CONCLUSIONS: HDE had a greater relative efficacy and safety in EA compared with Japan that was only partially explained by differences in baseline characteristics and TTR.

Efficacy and safety of edoxaban versus enoxaparin for the prevention of venous thromboembolism following total hip arthroplasty: STARS J-V.

BACKGROUND: In the absence of thromboprophylaxis, patients undergoing total hip arthroplasty (THA) are at increased risk for venous thromboembolism (VTE). The objective of this study was to compare the efficacy and safety of edoxaban with enoxaparin for the prevention of VTE after THA in Japan. METHODS: This was a phase 3, double-blind, double-dummy, noninferiority study. Patients undergoing elective, unilateral primary THA were randomized to receive edoxaban 30 mg once daily (n = 307) or enoxaparin 2000 IU (equivalent to 20 mg) twice daily (n = 303) for 11 to 14 days. The primary efficacy endpoint was the incidence of VTE. Safety endpoints included the incidence of major or clinically relevant nonmajor (CRNM) bleeding. RESULTS: The incidence of VTE, based on venography and clinical surveillance, was 2.4 % in the edoxaban group and 6.9 % in the enoxaparin group (P <0.001). The absolute difference in the incidence of VTE was -4.5 % (95 % confidence interval [CI]: -8.6, -0.9), which was within the noninferiority margin set at 8 % for the difference and established the noninferiority of edoxaban to enoxaparin. Since the upper limit of the 95 % CI of the absolute difference was less than 0 %, the superiority of edoxaban over enoxaparin was demonstrated. The incidence of major or CRNM bleeding was 2.6 % in the edoxaban group and 3.7 % in the enoxaparin group (P = 0.475). CONCLUSIONS: Oral edoxaban 30 mg once daily was superior to subcutaneous enoxaparin 2000 IU twice daily in the prevention of VTE following THA without increasing the risk for major or CRNM bleeding.