Cardiovascular risk of urate-lowering drugs: A study using the National Database of Health Insurance Claims and Specific Health Checkups of Japan.

In the present study, we aimed to investigate the association between urate-lowering 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 of Health Insurance Claims and Specific Health Checkups of Japan, including new urate-lowering drugs users between August 1, 2010, and March 31, 2018. Exposure and control groups were defined based on the first prescription of urate-lowering drugs as follows: febuxostat or topiroxostat for exposure groups, allopurinol for the control group, and benzbromarone for the secondary control group. The primary outcome was cardiovascular events, defined as a composite of acute coronary syndrome, cerebral infarction, and cerebral hemorrhage. Hazard ratios were estimated using a Cox proportional hazards model. The number of patients in each exposure and control group was 1,357,671 in the febuxostat group, 83,683 in the topiroxostat group, 1,273,211 in the allopurinol group, and 258,786 in the benzbromarone group. The adjusted hazard ratios for the cardiovascular risk were 0.97 (95% confidence interval [CI]: 0.95-0.98) for febuxostat and 0.84 (95% CI: 0.78-0.90) for topiroxostat groups. The benzbromarone group exhibited similar results. No increased cardiovascular risk was observed with febuxostat or topiroxostat when compared with allopurinol in patients with hyperuricemia in Japan. These results provide real-world evidence regarding the cardiovascular risk associated with urate-lowering drugs, indicating that no additional safety-related regulatory actions are warranted in Japan.

Use of National Database of Health Insurance Claims and Specific Health Checkups for examining practical utilization and safety signal of a drug to support regulatory assessment on postmarketing drug safety in Japan.

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.

Nested Case-Control Study Utilizing MID-NET® on Thrombocytopenia Associated With Pegfilgrastim in Patients Treated With Antineoplastic Agents.

Although several spontaneous case reports on the occurrence of thrombocytopenia in patients treated with human granulocyte colony-stimulating factor (G-CSF) preparations have been accumulated, its actual causality is still unclear. To investigate the association between G-CSF preparations (filgrastim, nartograstim, lenograstim, and pegfilgrastim) available in Japan and thrombocytopenia in patients treated with antineoplastic agents, a nested case-control study was conducted using the Medical Information Database NETwork (MID-NET®) with the cohort of the Japanese population taking antineoplastic agents between 2009 and 2018. A case of thrombocytopenia was defined as a patient who had decreased platelet counts (< 50,000/mm3 ). We identified a maximum of 10 controls for each case matched on the index date. Adjusted odds ratios (aORs) and their 95% confidence intervals (CIs) of thrombocytopenia for the use of G-CSF preparations compared with nonuse were estimated using conditional logistic regression. From the cohort in which 33,124 patients were included, 733 cases and 5,592 controls were identified. Compared with the nonuse of G-CSF preparations, the use of any G-CSF preparations increased the risk of thrombocytopenia (aOR: 5.7, 95% CI: 4.3-7.5). More detailed analysis showed that a distinctive increased risk was observed when pegfilgrastim was prescribed at 2-7 days before the index date (aOR: 7.4 95% CI: 2.0-28.1). Associations of the other G-CSF preparations with thrombocytopenia were unclear due to the inconsistent results among different analyses. A significantly increased risk of thrombocytopenia associated with pegfilgrastim was identified, leading to a revision of precautions in the package inserts of pegfilgrastim as a regulatory safety action.

Effect of Hepatitis C Drugs on Blood Coagulability in Patients on Warfarin Using the Medical Information Database Network (MID-NET®) in Japan.

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.