In the present study, we aimed to investigate the association between uratelowering drugs and cardiovascular events, primarily focusing on the risk of febuxostat and topiroxostat when compared with allopurinol in Japan. We conducted an observational study with a cohort design using the National Database

An association between kidney disease and direct-acting antivirals against hepatitis C (DAAs) has been suggested, however the warning on the package insert (PI) of the drug varies among DAAs. In this study, the risk of decreased kidney function associated with DAAs marketed in Japan was investigated to determine whether the risk of kidney disease is a common adverse event and class effect of DAAs. Data for patients who were new users of DAAs marketed in Japan, with eGFR ≥ 45 mL/min/1.73 m2 and without specific risk factors, were extracted from the MID-NET® medical information database network in Japan. Changes from the baseline on estimated glomerular filtration rate (eGFR) categories (eGFR ≥ 90, 90 > eGFR ≥ 60, 60 > eGFR ≥ 45, 45 > eGFR ≥ 30, 30 > eGFR ≥ 15, 15 > eGFR; unit: mL/min/1.73 m2) were used for evaluating the risk of decreased kidney function. Exposure groups for DAAs and relevant concomitant drugs were categorized into 10 patterns based on the PI. Among the 10 patterns, a significant increase in the incidence rate ratio (P < 0.01) was observed in the prescription patterns of concomitant use of telaprevir with peginterferon alpha and ribavirin, concomitant use of daclatasvir hydrochloride with asunaprevir, and ombitasvir hydrate combined with paritaprevir hydrate and ritonavir, which were concomitantly used with ribavirin; such an increase was not observed in the other prescription patterns. The effects of DAAs on kidney function may differ among drugs, suggesting the possibility that the risk of kidney disease is not a class effect of DAAs and should be evaluated individually for each DAA.

Background Previous studies suggested that direct-acting antivirals (DAAs) against hepatitis C increased the blood coagulability of patients on warfarin. This study aims to descriptively investigate the effects of DAAs on the blood coagulability and liver function of patients on warfarin in Japan. Methods The Medical Information Database Network (MID-NET®) was used as data source. Fluctuations of blood coagulability and liver function were examined before and after DAA treatment in patients who were prescribed both DAAs and warfarin at least once during the study period from January 1, 2010, to December 31, 2017. Results For the 16 eligible patients, the mean values of both PT-INR and WSI (warfarin sensitivity index) defined as the value obtained by dividing the PT-INR by the warfarin daily dose slightly decreased at the date of completion of the DAA treatment in comparison with those at the date of initiation and subsequently increased at 12 weeks after treatment completion. In contrast, the warfarin daily dose increased at the date of completion of the DAA treatment, followed by a decrease at 12 weeks after its completion. Several laboratory tests related to the liver function also revealed a similar decrease at the end of the DAA treatment. Conclusion The analysis of MID-NET® data provides useful information on drug safety assessment of real-world patients. The results of this study imply that fluctuation of the liver function test results may relate to the fluctuation of blood coagulability in patients on both DAA and warfarin. This study contributes to a deeper understanding of the usefulness and limitations of real-world data in MID-NET® for regulatory purposes.

The Pharmaceuticals and Medical Devices Agency (PMDA) has conducted many pharmacoepidemiological studies for postmarketing drug safety assessments based on real-world data from medical information databases. One of these databases is the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB), containing health insurance claims of almost all Japanese individuals (over 100 million) since April 2009. This article describes the PMDA’s regulatory experiences in utilizing the NDB for postmarketing drug safety assessment, especially focusing on the recent cases of use of the NDB to examine the practical utilization and safety signal of a drug. The studies helped support regulatory decision-making for postmarketing drug safety, such as considering a revision of prescribing information of a drug, confirming the appropriateness of safety measures, and checking safety signals in real-world situations. Different characteristics between the NDB and the MID-NET® (another database in Japan) were also discussed for appropriate selection of data source for drug safety assessment. Accumulated experiences of pharmacoepidemiological studies based on real-world data for postmarketing drug safety assessment will contribute to evolving regulatory decision-making based on real-world data in Japan.

Intestinal perforation and obstruction are known to be one of adverse events caused by antipsychotics; however, warning information on package inserts varies among antipsychotics. To investigate the risks of gastrointestinal perforation and intestinal obstruction in patients prescribed atypical antipsychotics compared with those in patients prescribed typical antipsychotics, a nested case-control study was conducted utilizing real-world data from the MID-NET® medical information database in Japan. The study period spanned from January 1, 2009, to December 31, 2018. Consequently, the risks of gastrointestinal perforation and intestinal obstruction in patients prescribed atypical antipsychotics were significantly lower than those in patients prescribed typical antipsychotics (adjusted odds ratio, 0.48; 95% confidence interval, 0.29–0.80). This finding was supported with prolonged periods for the exposure definition in the sensitivity analyses. In addition, no major differences in the risks of atypical antipsychotics, such as risperidone, quetiapine, olanzapine, and aripiprazole, were identified in this study. The safety profile regarding the lower risks of gastrointestinal perforation and intestinal obstruction in patients prescribed atypical antipsychotics should be considered when choosing antipsychotics in clinical practice in terms of the proper use of a drug.