Hisashi Urushihara

Chromosomal variability of human mesenchymal stem cells cultured under hypoxic conditions

Bone marrow derived human mesenchymal stem cells (hMSCs) have attracted great interest from both bench and clinical researchers because of their pluripotency and ease of expansion ex vivo. However, these cells do finally reach a senescent stage and lose their multipotent potential. Proliferation of these cells is limited up to the time of their senescence, which limits their supply, and they may accumulate chromosomal changes through ex vivo culturing. The safe, rapid expansion of hMSCs is critical for their clinical application. Chromosomal aberration is known as one of the hallmarks of human cancer, and therefore it is important to understand the chromosomal stability and variability of ex vivo expanded hMSCs before they are used widely in clinical applications. In this study, we examined the effects of culturing under ambient (20%) or physiologic (5%) O2 concentrations on the rate of cell proliferation and on the spontaneous transformation of hMSCs in primary culture and after expansion, because it has been reported that culturing under hypoxic conditions accelerates the propagation of hMSCs. Bone marrow samples were collected from 40 patients involved in clinical research. We found that hypoxic conditions promote cell proliferation more favourably than normoxic conditions. Chromosomal aberrations, including structural instability or aneuploidy, were detected in significantly earlier passages under hypoxic conditions than under normoxic culture conditions, suggesting that amplification of hMSCs in a low‐oxygen environment facilitated chromosomal instability. Furthermore, smoothed hazard‐function modelling of chromosomal aberrations showed increased hazard after the fourth passage under both sets of culture conditions, and showed a tendency to increase the detection rate of primary karyotypic abnormalities among donors aged 60 years and over. In conclusion, we propose that the continuous monitoring of hMSCs will be required before they are used in therapeutic applications in the clinic, especially when cells are cultured under hypoxic conditions.

Increased risk of acute pancreatitis in patients with type 2 diabetes: an observational study using a Japanese hospital database.

Background Increased risks of acute pancreatitis in patients with type 2 diabetes mellitus have been reported recently in several countries. We aimed to estimate the risks of acute pancreatitis in Japanese patients with diabetes mellitus. Methods/Findings We examined a large-scale hospital administrative database consisting of one million patients in 16 secondary medical care hospitals, from 2003 to 2010. The incidence rates of acute pancreatitis were estimated with cohort design; the odds ratios associated with diabetes mellitus and other comorbid risk factors were estimated with separate case-control analyses. In cohort analysis, the incidence of acute pancreatitis was higher in 14,707 diabetic patients than in 186,032 non-diabetic patients (4.75 vs. 1.65 per 1,000 patient-years) and increased in male patients and as age advanced. The adjusted odds ratio of acute pancreatitis in patients with diabetes mellitus was 1.86 (P<0.001) compared with non-diabetic patients in case-control analysis from 1,372 cases and 5,469 matched controls, which is consistent with the ones reported in previous studies. Alcoholism and gallstones were associated with a large increase in the risk of acute pancreatitis (adjusted odds ratio 13.40 and 14.29, respectively, P<0.001), although dyslipidemia was associated with significant risk reduction (adjusted odds ratio 0.62, P<0.001). Conclusions This observational study ascertained the elevated incidence rates and risk of acute pancreatitis in Japanese patients with diabetes. The risk estimates in Japanese patients with diabetes were in agreement with the ones reported in previous studies, and the elevated risk of acute pancreatitis in patients with diabetes would be generalized in different locations/populations.

Oseltamivir Prescription and Regulatory Actions Vis-à-Vis Abnormal Behavior Risk in Japan: Drug Utilization Study Using a Nationwide Pharmacy Database

Background In March 2007, a regulatory advisory was issued in Japan to restrict oseltamivir use in children aged 10-19 years because of safety concerns over abnormal behavior. The effectiveness and validity of regulatory risk minimization actions remain to be reviewed, despite their significant public health implications. To assess the impact of the regulatory actions on prescribing practices and safety reporting. Methodoloy/Prinicpal Findings In this retrospective review of a nationwide pharmacy database, we analyzed 100,344 dispensation records for oseltamivir and zanamivir for the period from November 2006 to March 2009. The time trend in dispensations for these antiviral agents was presented before and after the regulatory actions, contrasted with intensity of media coverage and the numbers of spontaneous adverse reaction reports with regard to antivirals. The 2007 regulatory actions, together with its intense media coverage, reduced oseltamivir dispensation in targeted patients in fiscal year 2008 to 20.4% of that in fiscal year 2006, although influenza activities were comparable between these fiscal years. In contrast, zanamivir dispensation increased approximately nine-fold across all age groups. The number of abnormal behavior reports associated with oseltamivir in children aged 10-19 years decreased from fiscal year 2006 to 2008 (24 to 9 cases); this decline was offset by the increased number of reports of abnormal behavior in children under age 10 (12 to 28 cases). The number of reports associated with zanamivir increased in proportion to increased dispensation of this drug (11 to 114 cases). Conclusions/Significance The 2007 actions effectively reduced oseltamivir prescriptions and the number of reports of abnormal behavior in the targeted group. The observed increase in abnormal behavior reports in oseltamivir patients under age 10 and in zanamivir patients suggests that these patient groups may also be at risk, calling into question the validity of the current discrimination by age and agent (Abstract translation is available in Japanese: Appendix S1).

Heterogeneity in responsiveness of perceived quality of life to body composition changes between adult- and childhood-onset Japanese hypopituitary adults with GH deficiency during GH replacement

OBJECTIVE To examine the responsiveness of quality of life (QoL) associated with changes in clinical indices relevant to GH deficiency (GHD) in Japanese hypopituitary adults. DESIGN AND METHODS QoL was determined using the Short Form (SF)-36 in Japanese adults with adult-(AO; n = 27) or childhood- (CO; n = 37) onset GHD in a 24-week double-blind placebo-controlled study with a fixed GH dose, and a subsequent 48-week open-label extension study with GH doses individualized using serum IGF-I levels. RESULTS Baseline QoL was significantly decreased from the Japanese national reference in both onset types, more so in AO patients. Throughout the study, AO patients showed a trend for an increase in physical functioning and general health (P = 0.0564 and 0.0999 respectively), whereas CO patients showed no changes in these domains. Fat mass changes negatively correlated with the changes in physical functioning and general health in AO patients (r = -0.42 and -0.64 respectively), but to a lesser degree in CO patients (r = -0.36 and -0.32 respectively). CO patients displayed significant decreases in social functioning (P = 0.0305) and mental health (P = 0.0442) and a decreasing trend in bodily pain (P = 0.0769), although no correlation between these decreases and any measured clinical index was observed, except between changes in bodily pain and IGF-I levels (r = -0.43). CONCLUSIONS QoL impairment was evident in Japanese adults with GHD, particularly in AO patients. In AO patients, general health and physical functioning domains were responsive to fat mass changes during GH treatment; this association was not evident in CO patients. These relationships between QoL and body composition warrant verification.

Raloxifene and stroke risks in Japanese postmenopausal women with osteoporosis on postmarketing surveillance.

Objective: The aim of this study was to assess whether the risks of stroke and stroke death in Japanese postmenopausal women with osteoporosis exposed to raloxifene increased in comparison with those of the general Japanese female population. Methods: Safety data associated with use of raloxifene were collected in observational settings from 6,970 women with a median follow-up period of 366 days on postmarketing surveillance conducted in Japan. The stroke incidences in raloxifene-treated women were compared with population stroke rates derived from epidemiology studies conducted at three distinct locations in Japan, yielding standardized morbidity ratios for stroke for the purpose of stroke risk assessment. Results: Exposure to raloxifene totaled 7,474 patient-years and 23 stroke cases were reported, including 4 fatal cases. Multiple stroke risk factors were present in three of four women with fatal outcome. The standardized stroke morbidity ratios in raloxifene-treated women versus women from the three reference regions, including Akita Prefecture, Takashima town in Shiga Prefecture, and Okinawa Prefecture, were 0.68 (95% CI, 0.45-1.02), 0.54 (95% CI, 0.35-0.83), and 0.82 (95% CI, 0.54-1.24), respectively. Conclusions: In this initial interim analysis, there seems to be no significant increased risk of stroke among Japanese women with 1 year of raloxifene use in comparison to Japanese epidemiological data. An increased risk of fatal stroke in the treatment population was indeterminable because of the small number of observed fatal cases. However, ongoing safety monitoring of stroke risk among raloxifene women will continue.

Quality of life in raloxifene-treated Japanese women with postmenopausal osteoporosis: a prospective, postmarketing observational study.

Abstract Objective: To assess changes in quality of life (QOL) and pain in raloxifene-treated Japanese women with postmenopausal osteoporosis. Research design and methods: This prospective, postmarketing observational study was conducted at 60 Japanese hospitals from September 2007 to February 2009 and included Japanese women with postmenopausal osteoporosis who were new to standard treatment with raloxifene (60 mg/day). Primary outcome measures (QOL and pain) were assessed using the Short Form-8 (SF-8), European Quality of Life Instrument (EQ-5D), osteoporosis-specific Japanese Osteoporosis Quality of Life Questionnaire (JOQOL), a visual analogue scale (VAS-pain), and a pain frequency survey. Assessments were performed at baseline and 8 (except JOQOL) and 24 weeks after first administration of raloxifene. Adverse drug reactions were recorded. Japan Pharmaceutical Information Center registration number: JapicCTI-070465. Results: A total of 506 participants, mean (±standard deviation [SD]) age = 70.7 ± 8.7 years, completed ≥1 follow-up assessment and were included in the analyses. All QOL scores increased from baseline during follow-up. All SF-8 domain scores increased significantly from baseline after 8 and 24 weeks (P < 0.001). Mean (±SD) EQ-5D scores increased significantly from baseline (0.70 ± 0.17) by 0.05 ± 0.15 after 8 weeks and 0.07 ± 0.17 after 24 weeks (P < 0.001). The mean (±SD) total JOQOL score increased significantly from baseline (66.8 ± 16.5) by 3.8 ± 11.3 after 24 weeks (P < 0.001). The percentage of participants with a ≥20 mm reduction in VAS-pain was 32.6% (120/368) and 39.5% (115/291) after 8 and 24 weeks, respectively. The frequency of pain reported by participants decreased after 8 and 24 weeks. Forty adverse drug reactions were reported by 34 participants. Limitations: Limitations include the lack of a control group, the possibility of the changes being due to the natural disease course, and potential selection bias. Conclusions: Our findings suggest that standard treatment with raloxifene improves QOL and relieves pain in Japanese women with postmenopausal osteoporosis in a real-world clinical setting.

Economic evaluation of pravastatin for primary prevention of coronary artery disease based on risk prediction from JALS-ECC in Japan

OBJECTIVES The clinical efficacy of 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase inhibitor (statin) therapy in cardiovascular disease has been established in clinical trials. Nonetheless, it is unclear to whom and when statin treatment should be initiated for patients without cardiovascular disease with regard to overall absolute risk reduction of cardiovascular disease and the cost-effectiveness of long-term statin therapy. The objective of this study was to examine the cost-effectiveness of pravastatin 10 mg/d compared with no-drug therapy for primary prevention of coronary artery disease (CAD), using cardiac risk factors from risk predictions for CAD from Japanese cohort studies. METHODS A Markov transition model was used to evaluate the cost-effectiveness of pravastatin compared with no-drug therapy. The incidence of acute myocardial infarction was estimated by using risk predictions for CAD in Japan. A hypothetical population from 45 to 75 years old was examined by using the cardiac risk factors. Quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratio over a lifetime horizon were estimated from a perspective of payers. RESULTS Incremental cost-effectiveness ratios of pravastatin therapy compared with no-drug therapy were 9,677,000 yen per QALY in 55-year-old men and 8,648,000 yen per QALY in 65-year-old men with diabetes mellitus, hypertension (grade II), and smoking as cardiac risk factors. Pravastatin therapy was not cost-effective compared with no-drug therapy in all subgroups evaluated. CONCLUSIONS Using risk prediction for CAD based on a Japanese cohort with no history of cardiovascular events, the cost-effectiveness of pravastatin for primary prevention of CAD may not be cost-effective in populations at both low and high cardiac risk.

Development Safety Update Reports and Proposals for Effective and Efficient Risk Communication

The periodic safety reporting to regulatory authorities is globally harmonized for postmarketing medicinal products by the International Conference on Harmonisation (ICH) guidelines, and is being extended for investigational drugs. To facilitate effective safety risk communication regarding investigational drugs, and to reduce duplicate periodic reporting to the US and EU by sponsors during development programmes, standardized Development Safety Update Reports (DSURs) are to be implemented in the near future.In this current opinion article, after extensively reviewing the relevant report from the CIOMS VII Working Group and the ICH draft guideline regarding DSURs, we discuss an effective and efficient approach to its application. To ensure effective risk communication, we recommend that DSURs be made available to all the ethics committees and participating investigators around the world for the purpose of continuing review during ongoing clinical trials.Furthermore, in order to maintain the consistency and integrity of safety information throughout the life-cycle of a drug, we believe it would be substantially more prudent and efficient to start a single, integrated, life-cycle periodic safety report covering both development and postmarketing, as proposed by the CIOMS VII Working Group, rather than maintain separate DSURs and Periodic Safety Update Reports, which can overlap considerably in content. To this end, we believe that the international regulatory community should undertake the new initiative for integrated periodic reporting immediately.

Biased safety reporting in blinded randomized clinical trials: meta-analysis of angiotensin receptor blocker trials.

Background Cough is listed as an adverse drug reaction (ADR) on the labels of angiotensin receptor blockers (ARB). However, a causal association with cough has also been reported for angiotensin converting enzyme inhibitors (ACEI), which have frequently been used as comparator drugs in the registration clinical trials of ARBs. This prompted us to examine the possible influence of using comparator drugs with well-known ADRs on the safety reporting of investigational drugs in blinded randomized clinical trials. Methods and Findings The double-blinded, randomized clinical trials with comparator drugs were identified in the Japanese dossiers for the new drug applications of ARBs. The risk ratios (RR) of reporting cough and headache in ARB arms were calculated for each ARB by comparing trials using ACEIs and trials using non-ACEIs, were then combined with a meta-analysis. 23 trials with a total of 6643 patients were identified, consisting 6 trials using an ACEI comparator including 819 ARB patients and 17 trials using a non-ACEI comparator including 5824 ARB patients. The combined RR of cough reporting was significantly elevated (20.77; 95% confidence interval [CI], 7.47 to 57.76), indicating more frequent reporting of cough in clinical trials using an ACEI comparator. In contrast, the combined RR of headache, a negative control, was insignificant (1.45; 95% CI, 0.34 to 6.22). Conclusion The use of comparators with well-known ADRs in blinded randomized trials produces potential bias in the reporting frequency of ADRs for investigational drugs. The selection of appropriate comparator drugs should be critical in unbiased safety assessment in double-blinded, randomized clinical trials and thus have relevance in reviewing the safety results from a regulatory point of view.

Night-to-night variability of sleep latency significantly predicts the magnitude of subsequent change in sleep latency during placebo administration

OBJECTIVE To investigate the association between subjective sleep latency (sSL) fluctuation during the lead-in period and the placebo response in the subsequent double-blind period. METHODS The current study is a secondary analysis of data from the placebo arm (380 patients) of a double-blind study in outpatients with primary insomnia. RESULTS Higher fluctuation of lead-in sSL was associated with a greater decrease in sSL in the subsequent weeks. Multivariate analysis suggested that a wider standard deviation for daily sSL and a higher weekly mean sSL during the lead-in period were independent predictors of greater improvement in mean sSL during the subsequent weeks of placebo treatment. Likewise, a wider standard deviation and lower mean of subjective total sleep time (sTST) during the lead-in period were independent predictors of greater improvement in mean sTST in the subsequent weeks, but predictability of change in sTST with these parameters appears lower than those for sSL (R(2)=0.13 and 0.44, respectively, in Week 2). CONCLUSIONS The importance of night-to-night variability of sSL in sleep assessment is highlighted. Excluding patients with high variability of lead-in sSL should be considered in clinical studies evaluating an effect on sleep onset, especially in the early stages of clinical development.