Possibility of Multiple Drug-Drug Interactions in Patients Treated with Statins: Analysis of Data from the Japanese Adverse Drug Event Report (JADER) Database and Verification by Animal Experiments.

Adverse drug events due to drug-drug interactions can be prevented by avoiding concomitant use of causative drugs; therefore, it is important to understand drug combinations that cause drug-drug interactions. Although many attempts to identify drug-drug interactions from real-world databases such as spontaneous reporting systems have been performed, little is known about drug-drug interactions caused by three or more drugs in polypharmacy, i.e., multiple drug-drug interactions. Therefore, we attempted to detect multiple drug-drug interactions using decision tree analysis using the Japanese Adverse Drug Event Report (JADER) database, a Japanese spontaneous reporting system. First, we used decision tree analysis to detect drug combinations that increase the risk of rhabdomyolysis in cases registered in the JADER database that used six statins. Next, the risk of three or more drug combinations that significantly increased the risk of rhabdomyolysis was validated with in vivo experiments in rats. The analysis identified a multiple drug-drug interaction signal only for pitavastatin. The reporting rate of rhabdomyolysis for pitavastatin in the JADER database was 0.09, and it increased to 0.16 in combination with allopurinol. Furthermore, the rate was even higher (0.40) in combination with valsartan. Additionally, necrosis of leg muscles was observed in some rats simultaneously treated with these three drugs, and their creatine kinase and myoglobin levels were elevated. The combination of pitavastatin, allopurinol, and valsartan should be treated with caution as a multiple drug-drug interaction. Since multiple drug-drug interactions were detected with decision tree analysis and the increased risk was verified in animal experiments, decision tree analysis is considered to be an effective method for detecting multiple drug-drug interactions.

Adverse Drug Events Caused by Drugs Contraindicated for Coadministration Reported in the Japanese Adverse Drug Event Report Database and Recognized by Reporters.

The "INTERACTIONS" section of package inserts aims to provide alert-type warnings in clinical practice; however, these also include many drug-drug interactions that occur rarely. Moreover, considering that drug-drug interaction alert systems were created based on package inserts, repeated alerts can lead to alert fatigue. Although investigations have been conducted to determine prescriptions that induce drug-drug interactions, no studies have focused explicitly on the adverse events induced by drug-drug interactions. We, therefore, sought to investigate the true occurrence of adverse events caused by drug pair contraindications for coadministration in routine clinical practice. Toward this, we created a list of drug combinations that were designated as "contraindications for coadministration" and extracted the cases of adverse drug events from the Japanese Adverse Drug Event Report database that occurred due to combined drug usage. We then calculated the reporters' recognition rate of the drug-drug interactions. Out of the 2121 investigated drug pairs, drug-drug interactions were reported in 43 pairs, 23 of which included an injected drug and many included catecholamines. Warfarin potassium and miconazole (19 reports), azathioprine and febuxostat (11 reports), and warfarin potassium and iguratimod (six reports) were among the 20 most-commonly reported oral medication pairs that were contraindicated for coadministration, for which recognition rates of drug-drug interactions were high. Although these results indicate that only a few drug pair contraindications for coadministration were associated with adverse drug events (43 pairs out of 2121 pairs), it remains necessary to translate these findings into clinical practice.

Categorisation of Pharmaceutical Adverse Events Using the Japanese Adverse Drug Event Report Database: Characteristic Adverse Drug Events of the Elderly Treated with Polypharmacy.

BACKGROUND: Pharmacokinetics and pharmacodynamics of drugs in elderly individuals differ from those in younger adults; thus, adverse drug events (ADEs) are common in older patients with polypharmacy because co-existing comorbidities elevate the risk of ADEs occurring. However, ADEs have not yet been characterised based on the elderly patients of Japanese origin and polypharmacy. OBJECTIVE: The 100 most commonly reported ADEs were grouped into four classes (Class 1-Class 4) based on elderly patients with polypharmacy. PATIENTS AND METHODS: In this study, logistic regression analysis was performed using cases recorded in the Japanese Adverse Drug Event Report (JADER) database. RESULTS: ADEs in elderly patients treated with polypharmacy-in whom the risk of electrolyte abnormalities, renal and respiratory disorders, and coagulopathy was high-were categorised as 'Class 1 [E(+), P(+)]', while ADEs in elderly patients not treated with polypharmacy-in whom the risk of delirium and fall was high-were categorised as 'Class 2 [E(+), P(-)]'. When there was no association with being elderly, ADEs associated with polypharmacy that carried a high risk of myelosuppression and infection were categorised as 'Class 3 [E(-), P(+)]', and allergic ADEs that were not affected by being elderly or polypharmacy, were categorised as 'Class 4 [E(-), P(-)]'. Class 1 events as well as Class 3 ADEs occurred more frequently in females than in males, whereas Class 3 ADEs (deep vein thrombosis and pulmonary embolism) occurred more frequently in males. CONCLUSIONS: Class 1 and Class 2 ADEs should be investigated in analyses that focus on individual drugs.

Discrepancies between patients' and pharmacists' perceptions of the role of community pharmacists as advisors on the use of pharmaceuticals in Japan: A comparison prior to and following revision of the Pharmacists' Act.

OBJECTIVES: In 2014, immediately prior to the revision of Article 25-2 of the Pharmacists' Act, we conducted a survey on pharmacists' and patients' perceptions of pharmacists' roles. A role discrepancy between the two was identified. The objective was to examine changes in role perceptions and awareness of pharmacists as medication specialists following revision to the Pharmacists' Act. METHODS: The survey was conducted using an Internet-based questionnaire. A total of 469 patients and 354 pharmacists responded to 12 questions about the perceived roles of pharmacists. RESULTS: Analysis revealed that the only evaluation that changed as a result of revisions was pharmacists' role as "family or regular pharmacist," with scores dropping by about half. As in 2014, the high rating rate for pharmacists surpassed the high rating of patients for all other items. The greatest discrepancy in role perception was observed for the same three items ("Understanding the effects of the drugs the patients are taking," "Understanding the health changes caused by the drugs dispensed to the patients," and "Consciously protecting patients from the adverse effects of drugs") as 2014. CONCLUSION: A major role discrepancy continues to exist between patients and pharmacists, and it is necessary for pharmacists to take on a more advanced role in patient care. Results suggest that pharmacists must monitor changes in patients' lifestyles and provide clear explanations for patients to rate them highly as medication specialists.

Acoustic cavitation as an enhancing mechanism of low-frequency sonophoresis for transdermal drug delivery.

We investigated the role of acoustic cavitation on sonophoretic skin permeation of calcein, a model permeant, across excised hairless rat skin. Three different frequencies (41, 158, 445 kHz) and various intensities (60 to 300 mW/cm(2)) of ultrasound were applied. Cavitation generation in degassed and undegassed (normal) water was monitored using a commercially available cavitation meter, then compared with skin permeability from calcein solution consistent of them. In addition, the penetration of a fluorescent dye, rhodamine B, into gelatin gel as a skin alternative was observed to estimate the role of cavitation collapse in the solution at or near the skin surface. Cavitation generation in the undegassed water was dependent on the ultrasound frequency, and the rank order of the cavitation was 41 kHz>158 kHz>445 kHz. At 41 kHz, cavitation generation in degassed water was clearly lower than that in undegassed water. Calcein permeability during ultrasound application correlated well with the cavitation generation in the medium, suggesting the important role of the indirect actions of cavitation collapse which occurred in the applied solution rather than the direct action in the skin. When ultrasound (41 or 158 kHz) was applied to the gelatin gels covered with rhodamine B solution, alteration in the surface configuration, like spots, and the coincident penetration of the dye were observed only at 41 kHz, while no alteration in the surface configuration was evident at 158 kHz. These results suggest that cavitation collapses in the vicinity of the skin surface might be more important for solute penetration in addition to skin permeabilization.

Quality of Japanese clinical trials estimated from good clinical practice audit findings.

To describe qualitatively recent changes in the Japanese clinical trial environments, we compared the results of the Good Clinical Practice (GCP) audits conducted from April 1997 to March 2000 (FY1997 to FY1999) with those from April 2002 to March 2003 (FY2002). In addition, the audit results were compared between the United States and Japan. The audit findings in the former period were based on the official audits by the Organization for Pharmaceutical Safety and Research (OPSR) that covered 331 hospitals and 775 trials. The audits by the OPSR in the latter period targeted 136 hospitals and 226 trials. The total number of deficiencies detected in the Good Clinical Practice audits in the former 3-year period (FY1997 to FY1999) was 1529, and the number in the single year (FY2002) was 1627. The total number of deficiencies detected and reported was about 3-fold on an annual basis between the periods. By category of deficiencies, there were 2 remarkable changes in the OPSR's audit findings between FY1997-FY1999 and FY2002. One was an increase in the proportion of protocol deviations from 14.7% (225/1529) in FY1997-FY1999 to 48.2% (785/1627) in FY2002, and the other was a decrease in the proportion of case report form-related deficiencies from 43.6% (666/1529) to 16.0% (260/1627). The high prevalence of protocol nonadherence and the relatively few findings of informed consent errors were important characteristics of Japanese trials inferred from the audit result reported by the OPSR in FY2002. In the United States, relatively high proportions of protocol nonadherence and informed consent errors were observed in the audit finding reported in 1997. Although the audit results for clinical trials between the United States and Japan are not strictly comparable, our results suggest that protocol deviations are a compelling issue for quality improvement in the conduct of clinical trials for the 2 regions.

Current status of quality in Japanese clinical trials.

The changes in the quality of Japanese clinical trials were evaluated by comparing the results of Good Clinical Practice (GCP) audits conducted from April 1997 to March 2000 (fiscal year (FY) 1997-1999) with those from April 2001 to March 2002 (FY2001). During both of the periods inspections were undertaken by the Organization for Pharmaceutical Safety and Research (OPSR). The audit findings in the former period were based on the audits that covered 331 hospitals and 775 trials conducted under the old GCP guideline. The audits in the latter period targeted 147 hospitals and 238 trials conducted under the old or new GCP guideline. The total number of deficiencies detected by GCP audits in the former three-year period (FY 1997-1999) was 1529, and the corresponding number in the latter single year (FY 2001) was 912. Two remarkable changes in OPSR's findings were observed between FY 1997-1999 and FY 2001 as follows; the proportion of protocol deviations increased from 14.7% (225/1529) to 53.1% (484/912), while the proportion of errors in case report forms (CRFs) decreased from 43.6% (666/1529) to 15.4% (140/912). The new GCP guideline sets very high standards for a hospital's qualification: to have sufficient equipment and hospital resources, to have capacity for promptly responding to urgent trial-related problems, to have an IRB, and to have appropriate staff including clinical research coordinators (CRCs) assigned to the clinical trial. Our results suggest that the impact of the regulatory changes of applicable standard is large for a hospital's qualification for conducting clinical trials in Japan.

Utilisation of human pharmacology studies with biomarkers for new drug applications in Japan.

OBJECTIVE: This study evaluated the utilisation of human pharmacology studies with biomarkers for either efficacy or safety estimation conducted for new drug applications (NDAs) submitted to the Japanese regulatory authority, the Ministry of Health, Labour and Welfare (MHLW). METHODS: A total of 50 new chemical entities (NCEs) posted on the Websites, which were approved from June 2000 to November 2001, were evaluated by investigating their approval information. The utilisation of human pharmacology studies with biomarkers was evaluated by focusing on the classification referred to biomarkers for either efficacy or safety estimation and timing of studies. RESULTS: The human pharmacology studies with biomarkers for either efficacy or safety estimation were conducted in 20 compounds classified by utilising measures of either efficacy (17 compounds) or safety (seven compounds). In 4 of 17 NCEs, some of the biomarkers in human pharmacology studies were similar to the clinical endpoints for efficacy assessment in therapeutic exploratory and/or therapeutic confirmatory studies. For safety assessment in therapeutic exploratory and/or therapeutic confirmatory studies, clinical endpoints rather than biomarkers in human pharmacology studies were used in all seven NCEs. The timing of each type of clinical study could only be obtained for 15 NCEs. Of these 15 NCEs, human pharmacology studies with biomarkers for either efficacy or safety estimation were conducted on six compounds. There were only two compounds for which human pharmacology studies with biomarkers for efficacy estimation were conducted before pivotal studies such as a therapeutic exploratory study or a bridging study. CONCLUSION: Our survey suggests that with Japanese NDAs, human pharmacology studies with biomarkers for either efficacy or safety estimation do not play a key role in accelerating drug development and maximising the knowledge gained from confirmatory trials. The relationship between a biomarker and a clinical endpoint should be investigated appropriately for accelerating drug development. We think that the utilisation of human pharmacology studies with biomarkers for either efficacy or safety estimation in the regulatory review process for NDAs should be encouraged with the advancements of drug evaluation research using an appropriate biomarker based on clinical pharmacology.

Elucidation of the transport pathway in hairless rat skin enhanced by low-frequency sonophoresis based on the solute-water transport relationship and confocal microscopy.

In this study, we examined a relationship between hydrophilic solute and water (vehicle) transports in the excised hairless rat skin in the presence of ultrasound (41 kHz, 60-300 mW/cm2) irradiation and also conducted skin surface observation using confocal microscopy. When the applied intensity was increased stepwise over the rage of 60-300 mW/cm2, the transport of tritiated water (3H2O) was increased 140-fold in an intensity-dependent manner and this returned to normal on stopping the ultrasound application. The skin permeation clearance (mul/h) of model hydrophilic solutes, calcein (MW 623) and FITC-labeled dextrans [MW 4400 (FD-4) and MW 38000 (FD-40)], across the skin under the influence of ultrasound was plotted against the corresponding 3H2O flux (microl/h) to estimate the potential contribution of convective solvent flow, induced by the ultrasound application, to the solute transport. Good correlations were observed between the 3H2O flux and solute clearances and, unexpectedly, the slope values obtained from linear regression of the plots were consistent for all solutes examined (1.04+/-0.29 for calcein, 1.07+/-0.17 for FD-4, and 1.08+/-0.23 for FD-40, respectively). Transport of intact FD-4 and FD-40 was confirmed by gel permeation chromatography. When the skin surface and deeper regions of the skin after sonophoresis of FD-40 were observed using a confocal microscope, the fluorescence of FD-40 was uniformly distributed in the area under the ultrasound horn and also evident in crack-like structures in the boundary of the horn. On the other hand, a hexagonal structure of horny cells in the stratum corneum (SC) observed by post-staining with rhodamine B was fully conserved in the area under the horn. These findings suggest that 41 kHz ultrasound can increase the transdermal transport of hydrophilic solutes by inducing convective solvent flow probably via both corneocytes and SC lipids as well as newly developed routes. Our observation also suggests that 41 kHz (low-frequency) ultrasound has the potential to deliver hydrophilic large molecules transdermally.

Characterization of transdermal solute transport induced by low-frequency ultrasound in the hairless rat skin.

Sonophoretic drug transport with low-frequency (41-445 kHz) and low-intensity (60-240 mW/cm2) ultrasound was characterized using hydrophilic calcein and deuterium oxide (D2O) as a solvent vehicle in excised hairless rat skin. The excised skin was mounted in vertical diffusion chambers for measurement of skin resistance and sonophoretic transport of calcein and D2O. The calcein content of the skin was also measured after ultrasound application. When the stratum corneum (sc) side was exposed to ultrasound at an intensity of 60 mW/cm2 for 30 min, the calcein flux in the sc-to-dermis direction was increased by 22.3-, 6.3-, and 3.8-fold from a baseline of 0.0088+/-0.0100 nmol/(cm2 x h) at frequencies of 41, 158, and 445 kHz, respectively, without significant changes in skin resistance. The ultrasonically-enhanced fluxes returned to baseline following cessation of the ultrasound application. At 41 kHz, there was a further increase in the magnitude of enhancement and a significant decrease in skin resistance (by 50% of the baseline resistance) on increasing the intensity from 60 to 120 mW/cm2, whereas no further enhancement was observed at 158 and 445 kHz up to 240 mW/cm2. Comparison of the calcein content in the skin before, during, and after ultrasound application at 41 kHz, 120 mW/cm2, was consistent with a transient ultrasonically-induced increase in calcein flux. In the sonophoretic transport experiments at 41 kHz, 120 mW/cm2, calcein transport correlated well with D2O transport. When 41-kHz ultrasound was applied to the sc side at 120 mW/cm2, the calcein and D2O fluxes in the sc-to-dermis direction were 13.7- and 5.2-fold higher than those in the dermis-to-sc direction. Similar directionality was also observed in tape-stripped skin, suggesting possible induction of convection in the direction of sound propagation. However, dermal application under the same ultrasound conditions induced neither an increase in calcein and D2O transport nor a decrease in skin resistance. These results demonstrate that low frequency sonophoresis is a potentially useful technique for controlling transdermal drug transport. Convective solvent flow as well as structural alteration of the skin induced by ultrasound are likely to be responsible for the observed sonophoretic transport enhancement.