Modeled Hepatic/Plasma Exposures of Omeprazole Prescribed Alone in Cytochrome P450 2C19 Poor Metabolizers Are Likely Associated with Hepatic Toxicity Reported in a Japanese Adverse Event Database.

Omeprazole, a gastric acid pump inhibitor, is repeatedly administered and is oxidatively metabolized mainly by polymorphic cytochrome P450 2C19. The prescribed dosage of omeprazole was discontinued or reduced in 47 of the 135 patients who received omeprazole alone in this survey, as recorded in the Japanese Adverse Drug Event Report database. The days to onset of omeprazole-related disorders were 3-4 d (median) and 16 d for intravenous 20-40 mg and oral 20 mg daily doses, respectively, in 34 patients for whom relevant data were available. The maximum plasma concentration of omeprazole was pharmacokinetically modeled after a single oral 40-mg dose in P450 2C19-defective poor metabolizers and was 2.4-fold higher than that in extensive metabolizers. The modeled area under the hepatic concentration curves of omeprazole in P450 2C19 poor metabolizers after virtual daily 40-mg doses for 7 d was 5.2-fold higher than that in the extensive metabolizers. Omeprazole-induced P450 2C19 (approx. 2-fold), resulting in increased hepatic intrinsic clearance in repeated doses, was considered after the second day. Virtual plasma/hepatic exposure estimated using pharmacokinetic modeling in subjects with P450 2C19 poor metabolizers indicated that these exposure levels virtually estimated could be one of causal factors for unexpected hepatic disorders induced by prescribed omeprazole, such as those resulting from drug interactions with repeatedly co-administered medicines.

Time-to-onset Analysis of Rhabdomyolysis due to Different Proton Pump Inhibitors Using a Pharmacovigilance Database.

BACKGROUND/AIM: Recent research has increasingly demonstrated an association between proton pump inhibitors (PPIs) and serious adverse events. This study aimed to evaluate the association between PPI and rhabdomyolysis (RM), examining its time-to-onset profiles using the Japanese Adverse Drug Event Report (JADER) database. PATIENTS AND METHODS: Data spanning from April 2004 to March 2022 were used. The association between PPIs and RM was evaluated using the reporting odds ratio (ROR), adjusted for sex and age. Subsequent analyses were conducted after excluding cases involving concomitant use of statins or fibrates. Furthermore, the onset time of RM and Weibull distribution parameters were calculated to evaluate the expression profile of RM, and the outcomes were examined. RESULTS: RM was associated with the use of esomeprazole, omeprazole, and rabeprazole, even in the absence of concomitant statin or fibrate use. The median time to RM onset varied among PPIs, ranging from 6.5 to 127 d. The Weibull distribution parameters indicated that the hazard types of nearly all orally administered PPIs were classified as early failure or close to random failure. Regarding outcomes, cases of death were reported for all PPIs except vonoprazan. CONCLUSION: The findings suggest the need for vigilant monitoring of RM during PPI administration, particularly in the early stages, considering the varying onset times.

Modeled Hepatic/Plasma Exposures of Fluvastatin Prescribed Alone in Subjects with Impaired Cytochrome P450 2C9*3 as One of Possible Determinant Factors Likely Associated with Hepatic Toxicity Reported in a Japanese Adverse Event Database.

Fluvastatin is a 3-hydroxy-3-methylglutaryl CoA reductase inhibitor that competitively inhibits human cytochrome P450 (P450) 2C9 in vitro. Drug interactions between a variety of P450 2C9 substrates/inhibitors and fluvastatin can increase the incidence of fluvastatin-related hepatic or skeletal muscle toxicity in vivo. In this survey, the prescribed dosage of fluvastatin was reduced or discontinued in 133 of 164 patients receiving fluvastatin alone, as recorded in the Japanese Adverse Drug Event Report database of spontaneously reported events. The median days to onset of fluvastatin-related disorders were in the range 30-35 d in the 87 patients. Therefore, we aimed to focus on fluvastatin and, using the pharmacokinetic modeling technique, estimated the virtual plasma and hepatic exposures in subjects harboring the impaired CYP2C9*3 allele. The plasma concentrations of fluvastatin modeled after a virtual oral 20-mg dose increased in homozygotes with CYP2C9*3; the area under the plasma concentration curve was 4.9-fold higher than that in Japanese homozygotes for wild-type CYP2C9*1. The modeled hepatic concentrations of fluvastatin in patients with CYP2C9*3/*3 after virtual daily 20-mg doses for 7 d were 31-fold higher than those in subjects with CYP2C9*1/*1. However, heterozygous Chinese patients with CYP2C9*1/*3 reportedly have a limited elevation (1.2-fold) in plasma maximum concentrations. Virtual hepatic/plasma exposures in subjects harboring the impaired CYP2C9*3 allele estimated using pharmacokinetic modeling indicate that such exposure could be a causal factor for hepatic disorders induced by fluvastatin prescribed alone in a manner similar to that for interactions with a variety of co-administered drugs.

Pharmacokinetic Models Scaled-up from Humanized-liver Mouse Data Can Account for Drug Monitoring Results of Atomoxetine and Its 4-Hydroxylated and N-Demethylated Metabolites i n Pediatric Patients Genotyped for Cytochrome P450 2D6.

Atomoxetine is a cytochrome P450 (P450) 2D6 probe substrate and an approved medicine for attention-deficit/hyperactivity disorder. In this humanized-liver mouse study, interactions between atomoxetine and the P450 2D6 probe drug paroxetine were observed. Human physiologically based pharmacokinetic (PBPK) models were established by scaling up humanized-liver mouse data obtained in the absence or presence of paroxetine. These models could explain the drug monitoring results of atomoxetine and its primary 4-hydroxylated and N-demethylated metabolites in Japanese children aged 8-14 years and could be used to help establish the correct dosage and for the evaluation of clinical outcomes. The results of simple PBPK models (using input parameters that reflected the subjects' small body size and normal or reduced P450 2D6-dependent clearance) were in general agreement with one-point measured plasma concentrations of atomoxetine and its 4-hydroxylated and N-demethylated metabolites in 13 pediatric participants. Unexpectedly high hepatic exposure, possibly in intermediate-metabolizer patients harboring CYP2D6*10 or 2D6*36 alleles, might in part explain the adverse effects of atomoxetine prescribed alone recorded in a Japanese adverse-event database. The steady-state, one-point drug monitoring data from the participants indicated extensive biotransformation of atomoxetine to 4-hydroxyatomoxetine under individually prescribed doses of atomoxetine. These results also suggest that a relatively narrow range of 4-hydroxyatomoxetine and N-desmethylatomoxetine concentration ratios in spot urine and/or plasma samples from pediatric patients could be a simple semiquantitative determinant factor for P450 2D6 intermediate metabolizers, compared with the wide range of concentrations of the two primary metabolites and substrate in extensive metabolizers. Significance Statement Validated simple pharmacokinetic models are able to predict steady-state plasma concentrations of the approved medicine atomoxetine and its primary metabolites in the majority of pediatric patients. The package insert advises careful dose escalation, especially for poor metabolizers; however, no simple way exists to determine P450 2D6 phenotypes. A relatively narrow range ratio of 4-hydroxyatomoxetine and N-desmethylatomoxetine in spot urine/plasma samples could be a simple semi-quantitative determinant factor for P450 2D6 intermediate metabolizers to optimize or confirm the correct dosage.

Association of Torsade de Pointes and QT Prolongation With Antifungal Triazoles: Analysis Using a Pharmacovigilance Database.

BACKGROUND/AIM: Torsade de pointes (TdP)/QT prolongation (QTP) is one of the most life-threatening adverse effects of antifungal triazoles. The aim of the present study was to evaluate the association of antifungal triazoles with TdP/QTP by age group and the profile of the time of TdP/QTP onset by analyzing the spontaneous adverse event database for Japan. PATIENTS AND METHODS: Data registered in the Japanese Adverse Drug Event Report database (JADER) from April 2004 to March 2022 were analyzed. The association between the administration of antifungal triazoles and TdP/QTP according to age was evaluated using an adjusted reporting odds ratio (aROR). In addition, the time-to-onset of TdP/QTP after antifungal triazole treatment was analyzed using the Weibull distribution according to the route of administration. RESULTS: Antifungal triazole treatment was associated with TdP/QTP (aROR=1.77, 95% confidence interval=1.52-2.07). In the subgroup analyses by age group, antifungal triazole treatments in patients ≤29 years old and ≥50 (except ≥90) years old were associated with TdP/QTP. The medians (quartiles) of time-to-onset for intravenous and oral antifungal triazole treatment were 8 (6-12) and 23 (8-86) days, respectively. In addition, the shape parameter in the Weibull distribution analysis of oral triazole treatment revealed that the hazard exhibited an early failure profile. CONCLUSION: TdP/QTP is associated with antifungal triazoles even in young patients, and patients should be monitored for the development of TdP/QTP, especially early after the initiation of treatment.

Plasma and Hepatic Exposures of Celecoxib and Diclofenac Prescribed Alone in Patients with Cytochrome P450 2C9*3 Modeled after Virtual Oral Administrations and Likely Associated with Adverse Drug Events Reported in a Japanese Database.

The impacts of polymorphic cytochrome P450 (P450 or CYP) 2C9 on drug interactions and the pharmacokinetics of cyclooxygenase inhibitors have attracted considerable attention. In this survey, the prescribed dosage was reduced or discontinued in 150 and 56 patients, respectively, receiving celecoxib and diclofenac prescribed alone, as recorded in a Japanese database of adverse drug events. Among the factors underlying adverse events, intrinsic drug clearance rates may be a contributing factor. The pharmacokinetically modeled plasma concentrations of celecoxib after an oral 200-mg dose increased in CYP2C9*3 homozygotes: the area under the plasma concentration curve was 4.7-fold higher than that in CYP2C9*1 homozygotes. In patients with CYP2C9*3/*3, the virtual hepatic concentrations of diclofenac after three daily 25-mg doses for a week were 11-fold higher than the plasma concentrations in subjects with CYP2C9*1/*1. The in vivo and in vitro fractions of the victim drug metabolized by a specific polymorphic P450 form is an important determining factor for estimating drug-drug interactions. Virtual hepatic and plasma exposures estimated by pharmacokinetic modeling in patients harboring the impaired CYP2C9*3 allele could represent a causal factor for adverse events induced by celecoxib or diclofenac in a manner similar to that for drug interactions.

High hepatic and plasma exposures of atorvastatin in subjects harboring impaired cytochrome P450 3A4∗16 modeled after virtual administrations and possibly associated with statin intolerance found in the Japanese adverse drug event report database.

Drug interactions between atorvastatin and cytochrome P450 (P450) 3A substrates/inhibitors lead to an increased incidence of skeletal muscle or hepatic toxicity. However, in this survey, among 483 Japanese subjects administered atorvastatin alone, more than half (258) experienced statin intolerance and were unable to continue using the drug. Although many factors underly atorvastatin toxicity, the intrinsic clearance rate might be a contributing causal factor. The impaired P450 3A4 p.Thr185Ser variant, CYP3A4∗16 (rs12721627), has been identified in East Asians with an allele frequency of 2.2%. Pharmacokinetically modeled plasma concentrations of atorvastatin increased after a virtual oral dose of 40 mg in CYP3A4∗16 homozygotes; the maximum concentration and area under the concentration curve, respectively, were 3.3-fold and 4.2-fold those in subjects homozygous for CYP3A4∗1. In subjects with CYP3A4∗16/∗16, the virtual hepatic concentrations of atorvastatin after daily doses of 10 mg for a week were similar to or higher than the plasma concentrations. These results suggest that the estimated high virtual plasma and hepatic exposures obtained by pharmacokinetic modeling in subjects harboring impaired allele CYP3A4∗16 may be one of the causal factors for statin intolerance in a manner similar to the well-known drug interactions caused by co-administrations of CYP3A inhibitors.

Inverse association between DPP-4 inhibitor use and fracture in older adults: A disproportionality analysis of the FAERS and JADER.

OBJECTIVE: Fractures are significantly associated with increased morbidity and mortality in older individuals; additionally, patients with diabetes mellitus are highly prone to fractures. The aim of the present study was to examine the association between dipeptidyl peptidase-4 (DPP-4) inhibitor use and the risk of fracture in older patients by analyzing data obtained from spontaneous adverse event reporting databases from the United States and Japan. MATERIALS AND METHODS: Data on older patients registered in the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) from the first quarter of 2013 to the end of 2019 and data registered in the Japanese Adverse Drug Event Report database (JADER) from April 2004 to December 2019 were used. Reporting odds ratio (ROR) and information component (IC) values were used for disproportionality analysis. RESULTS: Significant inverse associations between DPP-4 inhibitor use and fracture were found for DPP-4 inhibitors as a whole (ROR = 0.80; 95% CI = 0.73 - 0.88; IC = -0.31, 95% CI = -0.46 to -0.17); linagliptin (ROR = 0.74; 95% CI = 0.59 - 0.94; IC = -0.42, 95% CI = -0.75 to -0.08); and sitagliptin (ROR = 0.77; 95% CI = 0.68 - 0.88; IC = -0.36, 95% CI = -0.55 to -0.17) in the analyses of FAERS data. Similarly, significant inverse associations were also found for DPP-4 inhibitors as whole (ROR = 0.71; 95% CI = 0.59 to 0.86; IC = -0.46, 95% CI = -0.74 to -0.18); sitagliptin (ROR = 0.70; 95% CI = 0.52 - 0.95; IC = -0.49, 95% CI = -0.93 to -0.05); and vildagliptin (ROR = 0.54; 95% CI = 0.35 - 0.83; IC = -0.85, 95% CI = -1.49 to -0.22) in the analyses of JADER data. CONCLUSION: Our analysis of adverse event databases using different algorithms revealed that DPP-4 inhibitor use was inversely associated with fracture in older patients.

Effect of Concomitant Drug Use on the Onset and Exacerbation of Diabetes Mellitus in Everolimus-Treated Cancer.

PURPOSE: Everolimus-induced diabetes mellitus (DM) outcomes include everolimus-resistant tumors and poor hyperglycemia outcomes, which lead to various other negative clinical outcomes. This study aimed to evaluate the effect of associations between concomitant drug treatment and time to DM event occurrence (onset or exacerbation) on the outcomes of everolimus-induced DM in patients with cancer. METHODS: Data from the Japanese Adverse Drug Event Report database (JADER) were used, and patient drug use, time of DM event occurrence, and DM outcomes were determined from patient records. Associations between concomitant drug groups with everolimus and DM event occurrence were then evaluated for patients with both good and poor DM outcomes. RESULTS: Top ten groups used concomitantly were drugs for the treatment of hypertension (HT), controlled DM, constipation, hypothyroidism, kidney disease, insomnia, hyperlipidemia, hyperuricemia, anemia, and gastritis. Among them, only HT, controlled DM, and hyperlipidemia were associated with DM event occurrence. These three drug groups were examined by the outcome of everolimus concomitant usage and revealed a significantly shorter time to DM event occurrence for patients with poor outcomes than for those with good outcomes (p = 0.015) among patients without a concomitant drug for DM. Each of these three drug groups was analyzed on patients who were concomitantly administered with one of each drug group with everolimus and revealed a significantly shorter time to DM event occurrence for patients with poor outcomes than for those with good outcomes in patients who received concomitant HT drugs (p = 0.006). Moreover, among the four HT drug categories, calcium channel blockers were significantly associated with poor outcomes (odds ratio, 2.18 [1.09-4.34], p = 0.028). CONCLUSION: To prevent everolimus-induced poor DM outcomes, early DM detection and treatment are necessary, and the effect of the concomitant drug should be considered before initiating everolimus treatment.

Pharmacovigilance study of the association between dipeptidyl peptidase-4 inhibitors and angioedema using the FDA Adverse Event Reporting System (FAERS).

Dipeptidyl peptidase-4 (DPP-4) plays a minor role in degrading vasoactive peptides that cause angioedema when angiotensin-converting enzyme (ACE) is present and fully functional. This study investigated the association between DPP-4 inhibitors (DPP-4Is) and angioedema, including cases where the concomitant use of ACE inhibitors (ACEIs) was absent. We obtained data from the US Food and Drug Administration Adverse Event Reporting System and performed a disproportionality analysis, using the reporting odds ratio (ROR) and information component (IC) for signal detection in patients aged ≥ 40 years, stratified by age group and sex. No signal was detected for DPP-4Is when the entire dataset was analyzed. However, a signal was detected for the entire female subset group, the three stratified female groups aged ≥ 60 years, and males in their 40 s. After excluding the data of concomitant ACEI users, most ROR and IC values were lower and significant only for females in their 60 s and males aged ≥ 80 years. Regarding individual DPP-4Is signals, those detected for saxagliptin and sitagliptin in some age groups disappeared after excluding the data of ACEI users. Notably, linagliptin was the only DPP-4I where signals were detected in most female groups, regardless of age and without concomitant ACEI use. Our findings suggest that some DPP-4Is were associated with a higher reporting of angioedema as per age and sex, even in the absence of concomitant ACEI use.

Association of gynecomastia with antidiabetic medications in older adults: Data mining from different national pharmacovigilance databases.

OBJECTIVE: Gynecomastia is a benign proliferation of the glandular breast tissue in men and is generally caused by a decrease in androgen and an increase in estrogen. Diabetes has been reported to be a risk factor for lowering androgen levels. Moreover, lowered androgen levels are more common in older men. In the present study, we aimed to evaluate the signals for gynecomastia in older men on antidiabetic medications. MATERIALS AND METHODS: A disproportionality analysis was performed to detect the signals for antidiabetic drug-associated gynecomastia in the U.S. Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) and the Japanese Adverse Drug Event Report database (JADER), using the reporting odds ratio (ROR) and information component (IC). RESULTS: Among 8 classes of medications for diabetes, a signal was detected only for dipeptidyl peptidase-4 (DPP-4) inhibitors (ROR: 1.90, 95% confidence interval (CI): 1.27 - 2.83; IC: 0.84, 95% CI: 0.26 - 1.42) in the FAERS. Regarding individual drugs, ROR and IC signals were detected for sitagliptin (ROR: 2.37, 95% CI: 1.48 - 3.79; IC: 1.12, 95% CI: 0.44 - 1.79) and vildagliptin (ROR: 3.34, 95% CI: 1.39 - 8.08; IC: 1.26, 95% CI: 0.07 - 2.44) in the FAERS and only for sitagliptin (ROR: 4.84, 95% CI: 1.92 - 12.2; IC: 1.48, 95% CI: 0.24 - 2.73) in the JADER. CONCLUSION: This study showed an association between DPP-4 inhibitor use and gynecomastia in older men with diabetes. Further pharmacoepidemiological studies are warranted to verify this finding.

Association between anaphylaxis and anti-influenza drug use: An analysis of the Japanese Adverse Drug Event Report database.

We aimed to investigate the association between anaphylaxis and anti-influenza drug use using the Japanese Adverse Drug Event Report (JADER) database, a national spontaneous reporting database in Japan. We surveyed registered cases from the JADER database between April 2004 and November 2019. The target drugs were five anti-influenza drugs, namely oseltamivir, zanamivir, peramivir, laninamivir, and baloxavir. Adverse events associated with anaphylaxis, "anaphylactic reaction," "anaphylactic shock," "anaphylactoid reaction," and "anaphylactoid shock," were evaluated. The association between anaphylaxis and anti-influenza drug use was assessed by calculating the reporting odds ratio (ROR) and information component (IC) as a measure of disproportionality. Signals were considered positive if the lower limit of the 95% confidence interval (CI) of ROR was > 1, and that of IC was > 0. The number of anaphylaxis cases associated with anti-influenza drug use was 199 (0.9%). Signals were detected for inhaled laninamivir (ROR: 4.24 [95% CI: 3.06-5.88], IC: 1.83 [1.35-2.30]), intravenous peramivir (ROR: 2.97 [2.11-4.17], IC: 1.40 [0.90-1.89]), and oral baloxavir (ROR: 3.05 [2.22-4.18], IC: 1.44 [0.98-1.90]). Conversely, signals were not detected for oral oseltamivir or inhaled zanamivir. Although zanamivir and laninamivir were used as dry powder inhalers containing lactose as an additive, they differed in terms of signal detection. Our analysis indicated that the signal of anaphylaxis may varies based on the main component or dosage form of each anti-influenza drug. Appropriate use of these drugs is essential to prevent anaphylaxis and improve health status.

Analysis of the Time-To-Onset and Factors Affecting Clinical Outcomes of Immune Reconstitution Inflammatory Syndrome in People Living with HIV Using Data from the Japanese Spontaneous Reporting Database.

PURPOSE: Data on immune reconstitution inflammatory syndrome (IRIS), despite being a widely recognized complication of antiretroviral therapy, remain limited. The objective of the present study was to evaluate the time-to-onset and factors affecting clinical outcomes of IRIS in people living with HIV (PLWH) using data from the Japanese Adverse Drug Event Report (JADER) database. METHODS: Data of PLWH who developed IRIS as an adverse event were extracted from the JADER database. Cases with the data of both the start date of anti-HIV drug therapy and date of IRIS onset were included in the study. The survey items included sex, age, anti-HIV drug use, IRIS-compatible events, time-to-onset of IRIS, and clinical outcome. The time-to-onset of IRIS was evaluated in relation to anchor drug use. Overall, 79 cases were included in the analysis. RESULTS: The median (range) time-to-onset of IRIS was 29 (1-365) days, and it differed significantly between IRIS-compatible events (P = 0.029). In particular, the time-to-onset of Pneumocystis pneumonia-IRIS was the shortest among the IRIS-compatible events (median [range]: 12 [5-301] days). Age ≥ 50 years at IRIS onset appeared to be related to the poor clinical outcomes of IRIS in PLWH (P = 0.048). The use of integrase strand transfer inhibitors did not affect the time-to-onset of IRIS or clinical outcome of IRIS in PLWH. CONCLUSION: This analysis based on the data from the JADER database revealed that IRIS-compatible events were related to the time-to-onset of IRIS and that patients older than 50 years had poorer clinical outcomes of IRIS. This finding will be useful for healthcare professionals when considering medications for patients with HIV infection/AIDS and for the management of IRIS.

[Evaluation of the Association between Topical Prostaglandin F2α Analogs and Asthma Using the JADER Database: Comparison with ß-Blockers].

　Prostaglandin F2α (PGF2α) analog formulations are the most commonly used drugs for glaucoma treatment. They are known to be superior to ß-blockers for reducing intraocular pressure and can be effective all through the day. Because of the action, topical ß-blockers are contraindicated for patients with bronchial asthma. PGF2α is also known to act as a constrictor of the respiratory tract. The present study aims to analyze the relationship between PGF2α analogs and asthma. In addition, we utilized ß-blockers and combined formulations of both contents to evaluate for comparison with PGF2α analogs. Data from Japanese adverse drug event reports (JADERs) from April 2004 to January 2016 were used for analysis. The drugs of interest were 4 PGF2α analogs, 4 ß-blockers, and 2 combined formulations of both. For quantitative signal detection, the reporting odds ratios (RORs) with Haldane-Anscombe 1/2 correction were calculated. The corrected RORs (95%CI) were detected to be 4.73 (2.30-9.75) for PGF2α analogs, 4.61 (1.82-11.7) for ß-blockers, and 28.7 (12.1-68.1) for combined formulations. Our results suggest that not only topical ß-blockers but also PGF2α analogs are associated with asthma, and the combined formulations have stronger associations with asthma than when administered alone. Therefore, further clinical research will be necessary, and careful attention should be paid to any glaucoma patient using PGF2α analogs for asthma symptoms.

Blood Pressure Elevation Associated with Topical Prostaglandin F2α Analogs: An Analysis of the Different Spontaneous Adverse Event Report Databases.

Topical prostaglandin F2α (PGF2α) analogs are widely used as the first line of therapy for glaucoma. Systemic PGF2α is suggested to increase blood pressure. Some ophthalmic formulations with ß-receptor blocking or α-receptor stimulating actions are reported to cause systemic adverse events such as a decrease in heart rate and blood pressure. The objective of this study was to evaluate the association between topical PGF2α analogs and blood pressure elevation. We analyzed the reports obtained from the Food and Drug Administration Adverse Event Reporting System (FAERS) database from the first quarter of 2004 until the end of 2015 and the Japanese Adverse Drug Event Report (JADER) database from April 2004 to January 2016 for signal detection using reporting odds ratio (ROR), a method of disproportionality analyses. Signals are considered significant if the ROR estimates and lower bound of the 95% confidence interval (CI) exceed 1. Preferred terms in the Medical Dictionary for Regulatory Activities were utilized to define blood pressure elevation. A total of 6156081 reports from the FAERS and 351226 reports from the JADER were analyzed. The significant RORs with 95% CI were calculated to be 1.82 (95% CI: 1.55-2.13) for bimatoprost, 1.69 (95% CI: 1.53-1.85) for latanoprost, and 2.17 (95% CI: 1.82-2.59) for travoprost from the FAERS. From the JADER, 5.01 (95% CI: 1.59-15.8) was calculated for bimatoprost and 8.02 (95% CI: 2.94-21.9) for tafluprost. The resulting data suggest the necessity for further clinical research on blood pressure elevation associated with topical PGF2α analogs and close monitoring.

Association between Selective Beta-adrenergic Drugs and Blood Pressure Elevation: Data Mining of the Japanese Adverse Drug Event Report (JADER) Database.

Selective beta-adrenergic drugs are used clinically to treat various diseases. Because of imperfect receptor selectivity, beta-adrenergic drugs cause some adverse drug events by stimulating other adrenergic receptors. To examine the association between selective beta-adrenergic drugs and blood pressure elevation, we reviewed the Japanese Adverse Drug Event Reports (JADERs) submitted to the Japan Pharmaceuticals and Medical Devices Agency. We used the Medical Dictionary for Regulatory Activities (MedDRA) Preferred Terms extracted from Standardized MedDRA queries for hypertension to identify events related to blood pressure elevation. Spontaneous adverse event reports from April 2004 through May 2015 in JADERs, a data mining algorithm, and the reporting odds ratio (ROR) were used for quantitative signal detection, and assessed by the case/non-case method. Safety signals are considered significant if the ROR estimates and lower bound of the 95% confidence interval (CI) exceed 1. A total of 2021 reports were included in this study. Among the nine drugs examined, significant signals were found, based on the 95%CI for salbutamol (ROR: 9.94, 95%CI: 3.09-31.93) and mirabegron (ROR: 7.52, 95%CI: 4.89-11.55). The results of this study indicate that some selective beta-adrenergic drugs are associated with blood pressure elevation. Considering the frequency of their indications, attention should be paid to their use in elderly patients to avoid adverse events.

Drug interactions of diclofenac and its oxidative metabolite with human liver microsomal cytochrome P450 1A2-dependent drug oxidation.

1. The purpose of this study was to investigate the inhibitory effects of diclofenac on human cytochrome P450 1A2-, 2C19- and 3A4-mediated drug oxidations and to evaluate the drug interaction potential of diclofenac and 4'-hydroxydiclofenac. 2. Diclofenac was converted to 4'-hydroxydiclofenac by recombinantly expressed human P450 1A2 with Km and Vmax values of 33 µM and 0.20 min(-1), respectively. Diclofenac and 4'-hydroxydiclofenac suppressed flurbiprofen 4'-hydroxylation by P450 2C9 strongly and moderately, respectively; however, they did not affect P450 2C19-dependent S-mephenytoin hydroxylation or P450 3A4-dependent midazolam hydroxylation. 3. Although the caffeine 3-N-demethylation activity of liver microsomal P450 1A2 was inhibited by simultaneous incubation with diclofenac, the riluzole N-hydroxylation activities of recombinant P450 1A2 and human liver microsomes were inhibited after preincubation with diclofenac or 4'-hydroxydiclofenac for 20 min in the presence of NADPH. Using the inhibition constant (37 µM) of diclofenac on caffeine 3-N-demethylation and the reported 95th percentiles of maximum plasma concentration (10.5 µM) after an oral dose of diclofenac, the in vivo estimated increase in area under the plasma concentration-time curve was 29%. 4. These results suggest that diclofenac could inhibit drug clearance to a clinically important degree that depends on P450 1A2. Clinically relevant drug interactions in vivo with diclofenac are likely to be invoked via human P450 1A2 function in addition to those caused by the effect of diclofenac on P450 2C9.

Cytochrome P450-dependent drug oxidation activity of liver microsomes from Microminipigs, a possible new animal model for humans in non-clinical studies.

SUMMARY: Small minipigs (Bland name, Micromini Pig; registered as a novel variety of pig in the Japanese Ministry of Agriculture, Forestry and Fisheries) were developed with the aim of non-clinical pharmacological/toxicological use. They were principally mated with<10 kg body weight at 7 months-old resulting in good handling. Cytochrome P450 (P450)-and flavin-containing monooxygenases (FMO)-dependent drug oxidation activity of liver microsomes prepared from male Microminipigs (8 months-old) was compared with that for pooled dogs, monkeys, and humans. High P450 2D-dependent bufuralol 1'-hydroxylation and FMO-dependent benzydamine N-oxygenation activity was observed in liver microsomes from Microminipigs. Typical P450 1A, 2B, 2C, 2E, and 3A-dependent drug oxidation activity was also seen in Microminipigs. However, occasional differences might give undetected low P450 2A-dependent coumarin 7-hydroxylation in Microminipigs at 8-months-old, in contrast to liver microsomes from one 10-days-old Microminipis and commercially available pooled minipigs which had low but detectable coumarin 7-hydroxylation activity. The present results suggest that there is some overlap in Microminipig and human P450 substrate specificity. These findings should provide important information for greater understanding of drug metabolism in Microminipigs, as an experimental animal model for non-clinical use.

Roles of NADPH-P450 reductase and apo- and holo-cytochrome b5 on xenobiotic oxidations catalyzed by 12 recombinant human cytochrome P450s expressed in membranes of Escherichia coli.

Drug oxidation activities of 12 recombinant human cytochrome P450s (P450) coexpressed with human NADPH-P450 reductase (NPR) in bacterial membranes (P450/NPR membranes) were determined and compared with those of other recombinant systems and those of human liver microsomes. Addition of exogenous membrane-bound NPR to the P450/NPR membranes enhanced the catalytic activities of CYP2C8, CYP2C9, CYP2C19, CYP3A4, and CYP3A5. Enhancement of activities of CYP1A1, CYP1A2, CYP1B1, CYP2A6, CYP2B6, CYP2D6, and CYP2E1 in membranes was not observed after the addition of NPR (4 molar excess to each P450). Exogenous purified human cytochrome b5 (b5) further enhanced catalytic activities of CYP2A6, CYP2B6, CYP2C8, CYP2E1, CYP3A4, and CYP3A5/NPR membranes. Catalytic activities of CYP2C9 and CYP2C19 were enhanced by addition of b5 in reconstituted systems but not in the P450/NPR membranes. Apo b5 (devoid of heme) enhanced catalytic activities when added to both membrane and reconstituted systems, except for CYP2E1/NPR membranes and the reconstituted system containing purified CYP2E1 and NPR. Catalytic activities in P450/NPR membranes fortified with b5 were roughly similar to those measured with microsomes of insect cells coexpressing P450 with NPR (and b5) and/or human liver microsomes, based on equivalent P450 contents. These results suggest that interactions of P450 and NPR coexpressed in membranes or mixed in reconstituted systems appear to be different in some human CYP2 family enzymes, possibly due to a conformational role of b5. P450/NPR membrane systems containing b5 are useful models for prediction of the rates for liver microsomal P450-dependent drug oxidations.