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).     

Elevated cyclooxygenase-2 expression in patients with early gastric cancer in the gastric pylorus

Background Duodenogastric reflux after surgery increases the risk of gastric carcinoma. To determine whether bile reflux influences the development of gastric cancer in patients who have not had surgery, we compared cyclooxygenase-2 (COX-2) immunoreactivity in early gastric cancer originating from the gastric pylorus and that originating from other locations. We also examined the effects of bile acids on the expression and activity of COX-2 in gastric cells in vitro.Methods Tumor sections from 79 patients who underwent endoscopic mucosal resection for early intestinal-type gastric carcinoma were stained using a COX-2-specific monoclonal antibody. Immunoblotting of COX-2 was used to assess the effects of bile acids on COX-2 expression and activity in human gastric cell lines.Results Among the 79 early gastric cancer lesions studied, 13 (16%) arose in the gastric pylorus. In this group, COX-2 immunoreactivity was negative to weak in 38% (5 of 13 lesions) and moderate to strong in 62% (8 of 13 lesions). In the control group, COX-2 immunoreactivity was negative to weak in 70% (46 of 66 lesions) and moderate to strong in 30% (20 of 66 lesions). COX-2 expression was significantly elevated in early gastric cancer located in the gastric pylorus, compared with that in the other locations. In human gastric cell lines, bile acids induced COX-2 expression, mediated by the ERK 1/2 mitogen-activated protein kinase pathway.Conclusions COX-2 expression is elevated in early gastric cancer of the gastric pylorus, a common site of gastric cancer. Bile acids induced COX-2 expression in human gastric cell lines, suggesting a role of bile reflux in gastric carcinogenesis.     

Effects of age on hemodynamic changes after transcatheter closure of atrial septal defect: importance of ventricular diastolic function

Some older patients develop symptoms of clinical heart failure after closure of an atrial septal defect (ASD). The present study tested the hypothesis that baseline hemodynamics and hemodynamic changes induced by transcatheter ASD closure are different between younger and older patients due to age-related differences in left ventricular (LV) diastolic dysfunction. Forty-three consecutive patients (27.7 ± 16.3 years of age, range 5–63, median 25) who underwent device closure for ASD were divided into younger (age ≤25, n = 24, 15.1 ± 1.2 years) and older (> 25 years, n = 19, 43.7 ± 2.2 years) groups. Echocardiographic evaluations were performed 1 day before and 2 days after ASD closure. Before ASD repair, early diastolic mitral annular velocity (e′) on lateral, an index of ventricular relaxation, showed an age-related decrease. After closure, e′ decreased by similar amount in both groups (p < 0.05). In addition, E/e′, an index of LV filling pressure, was relatively unchanged in the younger group (from 5.4 to 5.9) but significantly increased (p < 0.05) in the older group (from 6.3 to 8.1) over similar increase of normalized LV diastolic dimension. In older patients, ASD closure resulted in further deterioration of baseline impairment in LV relaxation and the increased LV stiffness caused a more marked rise in LV filling pressure, compared to the younger group. Thus, ASD should be closed at a younger age before the development of age-related LV diastolic dysfunction.     

Phase I/II study of humanized anti-CD33 antibody conjugated with calicheamicin, gemtuzumab ozogamicin, in relapsed or refractory acute myeloid leukemia: final results of Japanese multicenter cooperative study

The primary objective of this study was to investigate the tolerability, efficacy and pharmacokinetic profile of gemtuzumab ozogamicin (GO) in patients with relapsed and/or refractory CD33-positive acute myeloid leukemia (AML). Patients received 2-h infusions of GO twice with an interval of approximately 14 days. Tolerability was assessed using the National Cancer Institute Common Toxicity Criteria Version 2.0. Samples for pharmacokinetics were taken on day 1 and day 8 of the first treatment cycle. The dose was increased stepwise and, in each cohort, patients were treated at the same dose. Forty patients, median age 58 years (range 28–68) were treated; 20 and 20 patients were enrolled to the phase I and II parts, respectively. In the phase I part, dose-limiting toxicities (DLTs) were hepatotoxicities, and the recommended dose was established as 9 mg/m² given as two intravenous infusions separated by approximately 14 days. The pharmacokinetic study revealed that C _max and AUC were equivalent to those of non-Japanese patients. In the phase II part, complete remission was observed in 5 patients, and one patient had complete remission without platelet recovery. Four of these 6 in remission and one in the phase I are long-term survivors (alive for at least 44 months). GO is safe and effective as a single agent among Japanese CD33-positive AML patients. Remission lasted longer in a subset of patients than in non-Japanese patients in earlier studies. Further studies of this agent are warranted to establish standard therapy. S. Furusawa: deceased.     

Interferon combined with cyclosporine treatment as an effective countermeasure against hepatitis C virus recurrence in liver transplant patients with end-stage hepatitis C virus related disease

Hepatitis C virus (HCV) is the most common cause of end-stage liver disease in transplant recipients. Progression of recurrent HCV infection is accelerated. Cyclosporine is not only an immunosuppressive drug, but also an anti-HCV drug. We reported here the beneficial effect of combined interferon and cyclosporine treatment for chronic hepatitis C. We recommend this protocol for established HCV-related graft disease.