Dabigatran-related serious medication errors: an analysis using data from VigiBase.

OBJECTIVE: To analyze the serious medication errors (MEs) on dabigatran, and their related factors, in order to avoid or reduce the occurrence of adverse events. METHODS: Serious MEs related to dabigatran were extracted from the WHO global database of reported potential side effects of medicinal products (VigiBase) by using "Medication errors and other product use errors and issues" High Level Group Term (HLGT) of the international Medical Dictionary for Regulatory Activities (MedDRA). Well-documented reports, vigiGrade completeness score ≥ 0.80, or with an informative narrative were analyzed with a focus on the clinical features of the cases. The PCNE Classification for drug-related problems (DRP) was used to classify medication errors in our analysis of cases. RESULTS: Until January 26, 2020, there were 453 cases with serious MEs related to dabigatran in VigiBase, and 113 were well-documented. Among these, 69 patients (61%) were hospitalized or had prolonged hospitalization, 16 (14%) had life-threatening events, and 12 (11%) died. The MEs occurred in the prescription phase in 77 cases, in administration in 35, and at the dispensing stage in one case. The MEs in prescription were related to a drug selection error in 44 cases (24 concerning contraindications and 20 drug interactions) and to dose error in 33 cases (17 with excessive dose; eight with insufficient frequency; four had an incorrect time; in three, the dose was too low; and in one, too frequent). The MEs in administration were medical-staff-related errors in five cases (three with wrong administration route, one administration omission, and one overdose), patient-related errors in 28 (14 insufficient dose or no administration, seven improper drug storage, four wrong administration method, and three over prescribed dose), and other errors in two (without efficacy monitoring). The dispensing error of a wrong drug strength occurred in a pharmacy. The main adverse events in the 113 patients were haemorrhage in 57 cases (50%) and ischemia in 29 cases (26%). CONCLUSION: Based on the analysis of reports in VigiBase, serious MEs related to dabigatran mainly occurred during prescription and administration. Although the incidence of MEs with clinical consequences in the use of dabigatran cannot be determined, attention should be paid to selection of the appropriate dose to a right patient in the prescription, and to patient compliance and storage in drug administration. The patient harm mainly manifested itself as bleeding or ischemia including fatal outcome in rare patients.

Fatal adverse events of rivaroxaban combined with aspirin: an analysis using data from VigiBase.

PURPOSE: The aim of this study was to analyze the clinical characteristics of fatal adverse events (AEs) of rivaroxaban combined with aspirin and to underline the importance of the rational use of drugs. METHODS: The WHO global database of reported potential side effects of medicinal products (VigiBase) was searched for fatal AEs in the combined use of rivaroxaban and aspirin, and the clinical characteristics of those cases with sufficient information (vigiGrade completeness score ≥ 0.80) were analyzed. RESULTS: By January 19, 2020, 2309 fatal adverse event reports of rivaroxaban combined with aspirin from 21 countries were entered in VigiBase. One hundred and twenty cases contained further information, of which 42 were female (35%) and 78 were male (65%). The median age was 75 (range 34 to 93) years, and 109 cases (91%) were elderly patients (≥ 65 years). The AEs listed in the fatal case reports included bleeding in 114 cases (mainly intracranial hemorrhage and gastrointestinal hemorrhage, 59 and 46 respectively, accounting for 88%) and ischemic events in six cases (ischemic stroke in three, acute myocardial infarction in two, myocardial infarction combined with acute liver failure in one). Among the patients with bleeding events, 108 (95%) had existing risk factors for bleeding or for interacting with aspirin or rivaroxaban. These may be divided into the following: diseases (hypertension, renal impairment, history of stroke, peptic ulcer, or previous bleeding), drugs (high dose aspirin, antiplatelet drugs, anticoagulants, P-gp inhibitors/CYP3A4 inhibitors, non-steroidal anti-inflammatory drugs, steroids, and selective serotonin reuptake inhibitors), or other factors (e.g., elderly, low body weight, or excessive intake of ginger, fish oil, or alcohol). There were 45 cases with two or more of these risk factors in addition to rivaroxaban and aspirin. Patients with ischemic events are often in very high-risk groups of atherosclerotic cardiovascular disease (ASCVD) or self-discontinuation of treated drugs. Medication errors occurred in 24 patients (20%): excessive treatment in 17 cases, contraindication in three, frequency error in two, excessive treatment combined with contraindication in one, and self-discontinuation in one. CONCLUSIONS: Fatal AEs related to rivaroxaban combined with aspirin, including bleeding and ischemic events, have been reported mostly in the elderly, and sometimes involved medication errors. The fatal AEs mainly manifested as serious bleeding, and most of them occurred in patients with concurrent multiple risk factors. Monitoring coagulation during rivaroxaban treatment is recommended in very high-risk ASCVD populations, and attention should be paid to prevention of medication errors.

SWEDEGENE-a Swedish nation-wide DNA sample collection for pharmacogenomic studies of serious adverse drug reactions.

SWEDEGENE is a Swedish nation-wide sample collection established to facilitate studies of clinical and genetic risk factors for adverse drug reactions (ADRs). Most cases are recruited among patients reported to the ADR registry at the Swedish Medical Products Agency by health-care professionals. Clinical data are collected both from medical and laboratory records and through interviews using standardized questionnaires. Genome-wide scans and whole-genome sequencing are done, and association studies are conducted using mainly controls from the Swedish TwinGene biobank with data on diagnoses and prescribed drugs. SWEDEGENE was established in 2008 and currently contains DNA and information from about 2550 adults who have experienced specific ADRs, and from 580 drug exposed controls. Results from genome-wide association studies have now been published, and data from whole-genome sequencing are being analyzed. SWEDEGENE has the potential to offer a new means of developing individualized and safe drug therapy through patient pre-treatment screening.

Genome-wide association study of angioedema induced by angiotensin-converting enzyme inhibitor and angiotensin receptor blocker treatment.

Angioedema in the mouth or upper airways is a feared adverse reaction to angiotensin-converting enzyme inhibitor (ACEi) and angiotensin receptor blocker (ARB) treatment, which is used for hypertension, heart failure and diabetes complications. This candidate gene and genome-wide association study aimed to identify genetic variants predisposing to angioedema induced by these drugs. The discovery cohort consisted of 173 cases and 4890 controls recruited in Sweden. In the candidate gene analysis, ETV6, BDKRB2, MME, and PRKCQ were nominally associated with angioedema (p < 0.05), but did not pass Bonferroni correction for multiple testing (p < 2.89 × 10-5). In the genome-wide analysis, intronic variants in the calcium-activated potassium channel subunit alpha-1 (KCNMA1) gene on chromosome 10 were significantly associated with angioedema (p < 5 × 10-8). Whilst the top KCNMA1 hit was not significant in the replication cohort (413 cases and 599 ACEi-exposed controls from the US and Northern Europe), a meta-analysis of the replication and discovery cohorts (in total 586 cases and 1944 ACEi-exposed controls) revealed that each variant allele increased the odds of experiencing angioedema 1.62 times (95% confidence interval 1.05-2.50, p = 0.030). Associated KCNMA1 variants are not known to be functional, but are in linkage disequilibrium with variants in transcription factor binding sites active in relevant tissues. In summary, our data suggest that common variation in KCNMA1 is associated with risk of angioedema induced by ACEi or ARB treatment. Future whole exome or genome sequencing studies will show whether rare variants in KCNMA1 or other genes contribute to the risk of ACEi- and ARB-induced angioedema.

A common missense variant of LILRB5 is associated with statin intolerance and myalgia.

Aims: A genetic variant in LILRB5 (leukocyte immunoglobulin-like receptor subfamily-B) (rs12975366: T > C: Asp247Gly) has been reported to be associated with lower creatine phosphokinase (CK) and lactate dehydrogenase (LDH) levels. Both biomarkers are released from injured muscle tissue, making this variant a potential candidate for susceptibility to muscle-related symptoms. We examined the association of this variant with statin intolerance ascertained from electronic medical records in the GoDARTS study. Methods and results: In the GoDARTS cohort, the LILRB5 Asp247 variant was associated with statin intolerance (SI) phenotypes; one defined as having raised CK and being non-adherent to therapy [odds ratio (OR) 1.81; 95% confidence interval (CI): 1.34-2.45] and the other as being intolerant to the lowest approved dose of a statin before being switched to two or more other statins (OR 1.36; 95% CI: 1.07-1.73). Those homozygous for Asp247 had increased odds of developing both definitions of intolerance. Importantly the second definition did not rely on CK elevations. These results were replicated in adjudicated cases of statin-induced myopathy in the PREDICTION-ADR consortium (OR1.48; 95% CI: 1.05-2.10) and for the development of myalgia in the JUPITER randomized clinical trial of rosuvastatin (OR1.35, 95% CI: 1.10-1.68). A meta-analysis across the studies showed a consistent association between Asp247Gly and outcomes associated with SI (OR1.34; 95% CI: 1.16-1.54). Conclusion: This study presents a novel immunogenetic factor associated with statin intolerance, an important risk factor for cardiovascular outcomes. The results suggest that true statin-induced myalgia and non-specific myalgia are distinct, with a potential role for the immune system in their development. We identify a genetic group that is more likely to be intolerant to their statins.

Comparison of Clinical Factors Between Patients With Angiotensin-Converting Enzyme Inhibitor-Induced Angioedema and Cough.

BACKGROUND: Angioedema is a rare and serious adverse drug reaction (ADR) to angiotensin-converting enzyme (ACE) inhibitor treatment. Dry cough is a common side effect of ACE inhibitors and has been identified as a possible risk factor for angioedema. OBJECTIVE: We compared characteristics between patients with ACE inhibitor-induced angioedema and cough with the aim of identifying risk factors that differ between these adverse events. METHODS: Data on patients with angioedema or cough induced by ACE inhibitors were collected from the Swedish database of spontaneously reported ADRs or from collaborating clinicians. Wilcoxon rank sum test, Fisher's exact test, and odds ratios (ORs) with 95% CIs were used to test for between-group differences. The significance threshold was set to P <0.00128 to correct for multiple comparisons. RESULTS: Clinical characteristics were compared between 168 patients with angioedema and 121 with cough only. Smoking and concomitant selective calcium channel blocker treatment were more frequent among patients with angioedema than cough: OR = 4.3, 95% CI = 2.1-8.9, P = 2.2 × 10-5, and OR = 3.7, 95% CI = 2.0-7.0, P = 1.7 × 10-5. Angioedema cases were seen more often in male patients (OR = 2.2, 95% CI = 1.4-3.6, P = 1.3 × 10-4) and had longer time to onset and higher doses than those with cough ( P = 3.2 × 10-10 and P = 2.6 × 10-4). A multiple model containing the variables smoking, concurrent calcium channel blocker treatment, male sex, and time to onset accounted for 26% of the variance between the groups. CONCLUSION: Smoking, comedication with selective calcium channel blockers, male sex, and longer treatment time were associated with ACE inhibitor-induced angioedema rather than cough.

Geographical variation in reporting Interstitial Lung Disease as an adverse drug reaction: findings from an European Medicines Agency analysis of reports in EudraVigilance.

PURPOSE: Clinically, interstitial lung disease (ILD) is a heterogeneous group of over 150 respiratory disorders. In the context of its signal evaluation work, the European Medicines Agency's (EMA) Pharmacovigilance Risk Assessment Committee (PRAC) has seen geographic clustering of case reports of ILD from Japan. To explore this further, EudraVigilance (EV), the EMA's database of adverse drug reactions (ADRs), was analysed. The results have been used to inform on implications for pharmacovigilance including signal detection and evaluation activities. METHODS: EV was queried for reports of respiratory ADRs coded using MedDRA for the period 1994-2014 for all medicinal products. Descriptive statistics and non-parametric (chi-square) independence tests were produced to compare reporting of ILD from Japan versus the rest of the world. RESULTS: As of 31 December 2014, there were 26 551 case reports of ILD in EV of which 17 526 (66%) originated in Japan. The reporting rate of ILD for Japan has been consistently higher over the period. The odds that a case report from Japan in EV refers to ILD is OR = 20.7, 95% CI 20.2, 21.3 (p < 0.001), compared to OR = 0.60, 95% CI 0.54, 0.67 (p < 0.001) for pulmonary fibrosis. CONCLUSIONS: A geographic imbalance between Japan and the rest of the world in reporting respiratory ADRs as ILD is confirmed. Consequently, the PRAC has developed approaches to address this in relation to signals of ILD it assesses to allow for more targeted risk minimisation including updates to the product information in the EU setting. Copyright © 2016 John Wiley & Sons, Ltd.

Susceptibility to amoxicillin-clavulanate-induced liver injury is influenced by multiple HLA class I and II alleles.

BACKGROUND & AIMS: Drug-induced liver injury (DILI), especially from antimicrobial agents, is an important cause of serious liver disease. Amoxicillin-clavulanate (AC) is a leading cause of idiosyncratic DILI, but little is understood about genetic susceptibility to this adverse reaction. METHODS: We performed a genome-wide association study using 822,927 single nucleotide polymorphism (SNP) markers from 201 White European and US cases of DILI following AC administration (AC-DILI) and 532 population controls, matched for genetic background. RESULTS: AC-DILI was associated with many loci in the major histocompatibility complex. The strongest effect was with an HLA class II SNP (rs9274407, P=4.8×10(-14)), which correlated with rs3135388, a tag SNP of HLA-DRB1*1501-DQB1*0602 that was previously associated with AC-DILI. Conditioned on rs3135388, rs9274407 is still significant (P=1.1×10(-4)). An independent association was observed in the class I region (rs2523822, P=1.8×10(-10)), related to HLA-A*0201. The most significant class I and II SNPs showed statistical interaction (P=.0015). High-resolution HLA genotyping (177 cases and 219 controls) confirmed associations of HLA-A*0201 (P=2×10(-6)) and HLA-DQB1*0602 (P=5×10(-10)) and their interaction (P=.005). Additional, population-dependent effects were observed in HLA alleles with nominal significance. In an analysis of autoimmune-related genes, rs2476601 in the gene PTPN22 was associated (P=1.3×10(-4)). CONCLUSIONS: Class I and II HLA genotypes affect susceptibility to AC-DILI, indicating the importance of the adaptive immune response in pathogenesis. The HLA genotypes identified will be useful in studies of the pathogenesis of AC-DILI but have limited utility as predictive or diagnostic biomarkers because of the low positive predictive values.

Indapamide-Induced Rhabdomyolysis: An Evaluation of Case Reports in VigiBase Using the Bradford Hill Criteria.

BACKGROUND: Indapamide can cause hypokalaemia and hyponatraemia. Rhabdomyolysis associated with these electrolyte abnormalities has been reported. OBJECTIVE: The aim of this study was to assess causal association between the use of indapamide and the occurrence of rhabdomyolysis using the Bradford Hill criteria. METHODS: Variables in the rhabdomyolysis case reports and literature were reviewed. Bradford Hill criteria were used in the assessment of causal association. RESULTS: Up to 11 November 2020, there were 28 unique cases in VigiBase from 13 countries reporting indapamide-associated rhabdomyolysis. In 18 of these cases, hypokalaemia (n = 14) or hyponatremia (n = 8) was a co-reported event, including four cases where both of these events were reported. Indapamide was the only suspected drug in nine of these 18 cases and positive dechallenge was mentioned in 13 of them. In addition, there were risk factors such as falls, concomitant drugs with risk of hypokalaemia, or muscle injury. In two cases, liquorice (containing glycyrrhizin) was concomitantly used with indapamide before hypokalaemia and rhabdomyolysis occurred. Thiazide diuretics, known to cause hypokalaemia, showed similar disproportionality patterns as indapamide regarding rhabdomyolysis and myopathy, while calcium channel blockers (not causing hypokalaemia), had lower disproportionality values than indapamide. CONCLUSIONS: Based on the review of case series and causality assessment using Bradford Hill criteria, indapamide may cause rhabdomyolysis due to hypokalaemia or hyponatremia. Considering the seriousness of the reported cases, health care professionals should be aware of this potential risk following indapamide intake, particularly when there are risk factors for hypokalaemia and hyponatremia such as excessive liquorice consumption. A similar risk of muscle injuries may apply to thiazide diuretics as well.

Montelukast and Nightmares: Further Characterisation Using Data from VigiBase.

INTRODUCTION: Montelukast is a medicine indicated for use in asthma. Psychiatric disorders including nightmares have not been described in clinical trials but during recent years have been included in the product information as having been reported post-marketing, without further description of the events. Previous descriptions in the scientific literature were based on limited numbers of reports or lacked detailed case information. OBJECTIVE: The study aim was to further characterise post-marketing adverse drug reactions for nightmares, suspected to be induced by montelukast, to facilitate safer use of the medicine by providing additional information to patients and healthcare professionals. METHODS: We clinically reviewed reports of nightmares with montelukast present in VigiBase, World Health Organization's global database of suspected adverse reactions to medicinal products, developed and maintained by the Uppsala Monitoring Centre, until 3 May, 2020. RESULTS: There were 1118 reports of nightmares with montelukast in VigiBase, which provided valuable descriptions of the nightmares as well as information about the impact on the daily lives, with many cases describing a severe impact of the nightmares. About half of the reports were classified as serious. Two thirds concerned children, with the largest age group represented being children aged 5-10 years. In most cases, the nightmares disappeared upon discontinuation of the drug but for some patients it took a long time until the nightmares ceased. CONCLUSIONS: The nature and potential severity of this adverse drug reaction, as described in these reports, present important knowledge for patients and healthcare providers that could help reduce drug-induced harm. This study highlights the value of post-marketing reports for further characterisation of known adverse drug reactions. The benefit-risk balance should be continuously monitored while patients are taking montelukast.

Global safety monitoring of COVID-19 vaccines: how pharmacovigilance rose to the challenge.

Pharmacovigilance (PV) came suddenly into the spotlight when several new vaccines, developed as a response to the COVID-19 pandemic, received emergency authorisation and were rolled out on a large scale in late 2020. The vaccines underwent stringent clinical trials and evaluation from regulatory authorities, but with the use of novel technology and an anticipated rapid and vast deployment of the vaccines, the importance of a well-functioning international post marketing safety surveillance system was stressed. International PV stakeholders were faced with several challenges due to the extent of the global vaccination campaign. The unprecedented volume of reports of suspected adverse events following immunization has led to the development and use of new tools. Furthermore, the collaboration between various PV stakeholders was encouraged and strengthened. PV rose to the challenges posed by the currently ongoing global COVID-19 vaccination campaign and successful adaptations were made in a short period of time. However, the pandemic has not ended yet, the vaccination campaign is far from being completed, and further challenges are anticipated. Advances made during the pandemic will be important to strengthen PV in future and ensure to advance medicines' safety together. Plain Language Summary: Global safety monitoring of the COVID-19 vaccines: challenges, preparations, and outlooks Pharmacovigilance (PV) is the umbrella term for all sciences and activities relating to the detection, assessment, understanding, and prevention of adverse effects relating to medicines or vaccines. PV came into the spotlight when several new vaccines were authorised and rolled out as a response to the COVID-19 pandemic.The anticipated extent of the global vaccine rollout stressed the importance of a well-functioning safety surveillance system and international collaborations between patients, health care workers, vaccine producers, regulatory authorities, and PV centres.The identification and communication of potential safety concerns showed that adaptations to PV processes made in a short period of time as well as international collaborations were successful. However, it is important to learn from experiences made so far and to make sure the positive advances are maintained in the future to advance medicines' safety together.

Appendicitis as a possible safety signal for the COVID-19 vaccines.

This study reviewed cases of appendicitis following administration of COVID-19 vaccines reported to VigiBase, the WHO database of individual case safety reports (ICSRs). Three hundred fifty-eight cases were identified, and disproportionate reporting was noted, with 329 calculated expected cases. Upon review, 24 ICSRs were excluded, so 334 unique ICSRs underwent clinical review from 19 countries. Forty-eight percent of ICSRs reported imaging and 69% noted surgical intervention. The cases were clinically coherent, with an apparent increase in reporting in the four days post-vaccination and a possible dose-response relationship. Appendicitis has been suggested as an adverse event of special interest post-vaccination against COVID-19 after a numerical increase in the vaccine arm of a clinical trial. The case series may be affected by differences in global patterns of reporting, and it is not possible to prove nor disprove causality from this case series. Global longitudinal studies are required to clarify any possible relationship.

Fatal Adverse Events of Dabigatran Combined With Aspirin in Elderly Patients: An Analysis Using Data From VigiBase.

Introduction: The elderly are vulnerable to cardiovascular diseases and the incidence of atrial fibrillation (AF) and venous thromboembolism (VTE) increases significantly with age. Dabigatran is a commonly used new oral anticoagulant approved by the FDA for stroke prevention in patients with non-valvular AF and VTE treatment and prevention. Aspirin is commonly used as a preventive drug for cardiovascular diseases. AF and coronary heart disease share many risk factors, so these two diseases often coexist and thus dabigatran and aspirin are often combined in those people. The aim of this study was to analyze the clinical characteristics of fatal adverse events of dabigatran combined with aspirin in elderly patients, and to provide references for clinical rational use of drugs. Materials and Methods: Fatal adverse events related to the combined use of dabigatran and aspirin in elderly patients aged over 75 were extracted from the WHO global database of individual case safety reports (VigiBase). Well-documented reports, vigiGrade completeness score ≥0.80, or with an informative narrative, were analyzed with a focus on the clinical features of the cases. Results: From 1968 up to January 19, 2020, there were 112 eligible reports in VigiBase from 13 countries, of which 33 were identified as well-documented. Of these 33, 19 were male (58%) and 14 were female (42%), the average age of the patients was 84 (75-95 years), with five cases of extreme weights (>100 kg in one case, <50 kg in four cases). There were 31 cases of death by internal bleeding (mainly 15 of gastrointestinal hemorrhage and 12 of intracranial hemorrhage) and two cases of the sudden death of unknown cause. Medication errors existed in 15 patients. The times to onset (TTO) was provided in 24 cases, ranging from 2 days to 4 years, and in 12 patients occurred within a month. Of the 31 patients with fatal bleeding events, 29 were associated with other factors that increase the risk of bleeding, such as diseases (hypertension, renal impairment, stroke, gastrointestinal related diseases, hypothyroidism, and cancer), drugs (antiplatelets, anticoagulants, thrombolytics, P glycoprotein substrates, non-steroidal anti-inflammatory drugs, hormones, selective serotonin reuptake inhibitors, and acetaminophen) and other factors (low body weights and alcohol consumption), and 21 of these contained two or more risk factors. Conclusion: The fatal adverse events associated with the combined use of dabigatran and aspirin in elderly patients were mainly serious bleeding events, which often occurred within 1 month. Most of these cases had medication errors and most of the patients had multiple diseases, medications, or other conditions at the same time that increase the risk of bleeding. It is suggested that prescription of dabigatran and aspirin in elderly patients should go along with alertness for medication errors, care for correct dose or control of other bleeding risk factors, and the combined medication time should be as short as possible to minimise serious adverse events.

Tumor necrosis factor inhibitor-induced pleuropericarditis: A retrospective evaluation using data from VigiBase.

OBJECTIVE: The aim of this study was to assess the causality of anti-TNFα agents-associated pleuropericarditis in VigiBase with a focus on its diverse types. METHODS: All variables contained in the pleuropericarditis reports were reviewed. Well-documented reports, vigiGrade completeness score ≥ 0.80 or with an informative narrative, were analyzed and with a focus on the clinical features of the cases. Bradford-Hill criteria were used in the case series assessment of causality. RESULTS: From 1968 up to 18 December 2019, there were 94 unique cases from 18 countries reporting pleuropericarditis with anti-TNFα agents as a suspected or interacting medicine. Among the 94 reports, 42 were identified as well-documented and further assessed for clinical features. Of the 42 cases, 39 were serious, including three fatal and seven life-threatening. In 35 cases, an anti-TNFα agent was the only suspected drug. Positive de- and re-challenge were reported in 95% and 17% of the 42 cases, respectively. The times to onset (TTO) varied greatly among individual cases, ranging from one month to 75 months (mean = 24 months). The most commonly involved anti-TNFα agents were adalimumab, infliximab and etanercept; and the mostly reported pleuropericarditis types were classified as autoimmune-related with (n = 17) or without (n = 15) co-reported drug-induced lupus (DIL), or infection-related (n = 8). While adalimumab was the most reported in the infection-related cases (7/8), infliximab was the most frequent in the autoimmune-related cases, in particular co-reported with DIL (9/17). There were four cases where the reaction occurred one to two months after the anti-TNFα agents (infliximab and adalimumab) were stopped. Based on the review of the case series using Bradford-Hill criteria the anti-TNFα agents associated pleuropericarditis are considered as a class effect. CONCLUSIONS: To clinically recognize and manage these potentially life-threatening serious cardiopulmonary complications, health care professionals should be aware of this possible risk. Meanwhile, attention should be paid to the clinical features of pleuropericarditis cases, since they may cause diagnostic and therapeutic difficulties. Considering the long elimination time, clinicians need to be reminded to remain vigilant for the adverse reactions even after discontinuing anti-TNFα therapy.

Exome Sequencing Reveals Common and Rare Variants in F5 Associated With ACE Inhibitor and Angiotensin Receptor Blocker-Induced Angioedema.

Angioedema occurring in the head and neck region is a rare and sometimes life-threatening adverse reaction to angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs). Few studies have investigated the association of common variants with this extreme reaction, but none have explored the combined influence of rare variants yet. Adjudicated cases of ACEI-induced angioedema (ACEI-AE) or ARB-induced angioedema (ARB-AE) and controls were recruited at five different centers. Sequencing of 1,066 samples (408 ACEI-AE, ARB-AE, and 658 controls) was performed using exome-enriched sequence data. A common variant of the F5 gene that causes an increase in blood clotting (rs6025, p.Arg506Gln, also called factor V Leiden), was significantly associated with both ACEI-AE and ARB-AE (odds ratio: 2.85, 95% confidence interval (CI), 1.89-4.25). A burden test analysis of five rare missense variants in F5 was also found to be associated with ACEI-AE or ARB-AE, P = 2.09 × 10-3 . A combined gene risk score of these variants, and the common variants rs6025 and rs6020, showed that individuals carrying at least one variant had 2.21 (95% CI, 1.49-3.27, P = 6.30 × 10-9 ) times the odds of having ACEI-AE or ARB-AE. The increased risk due to the common Leiden allele was confirmed in a genome-wide association study from the United States. A high risk of angioedema was also observed for the rs6020 variant that is the main coagulation defect-causing variant in black African and Asian populations. We found that deleterious missense variants in F5 are associated with an increased risk of ACEI-AE or ARB-AE.

Pandemrix-induced narcolepsy is associated with genes related to immunity and neuronal survival.

BACKGROUND: The incidence of narcolepsy rose sharply after the swine influenza A (H1N1) vaccination campaign with Pandemrix. Narcolepsy is an immune-related disorder with excessive daytime sleepiness. The most frequent form is strongly associated with HLA-DQB1*06:02, but only a minority of carriers develop narcolepsy. We aimed to identify genetic markers that predispose to Pandemrix-induced narcolepsy. METHODS: We tested for genome-wide and candidate gene associations in 42 narcolepsy cases and 4981 controls. Genotyping was performed on Illumina arrays, HLA alleles were imputed using SNP2HLA, and single nucleotide polymorphisms were imputed using the haplotype reference consortium panel. The genome-wide significance threshold was p < 5 × 10-8, and the nominal threshold was p < 0.05. Results were replicated in 32 cases and 7125 controls. Chromatin data was used for functional annotation. FINDINGS: Carrying HLA-DQB1*06:02 was significantly associated with narcolepsy, odds ratio (OR) 39.4 [95% confidence interval (CI) 11.3, 137], p = 7.9 × 10-9. After adjustment for HLA, GDNF-AS1 (rs62360233) was significantly associated, OR = 8.7 [95% CI 4.2, 17.5], p = 2.6 × 10-9, and this was replicated, OR = 3.4 [95% CI 1.2-9.6], p = 0.022. Functional analysis revealed variants in high LD with rs62360233 that might explain the detected association. The candidate immune-gene locus TRAJ (rs1154155) was nominally associated in both the discovery and replication cohorts, meta-analysis OR = 2.0 [95% CI 1.4, 2.8], p = 0.0002. INTERPRETATION: We found a novel association between Pandemrix-induced narcolepsy and the non-coding RNA gene GDNF-AS1, which has been shown to regulate expression of the essential neurotrophic factor GDNF. Changes in regulation of GDNF have been associated with neurodegenerative diseases. This finding may increase the understanding of disease mechanisms underlying narcolepsy. Associations between Pandemrix-induced narcolepsy and immune-related genes were replicated.

Pharmacogenomics of statin-related myopathy: Meta-analysis of rare variants from whole-exome sequencing.

AIMS: Statin-related myopathy (SRM), which includes rhabdomyolysis, is an uncommon but important adverse drug reaction because the number of people prescribed statins world-wide is large. Previous association studies of common genetic variants have had limited success in identifying a genetic basis for this adverse drug reaction. We conducted a multi-site whole-exome sequencing study to investigate whether rare coding variants confer an increased risk of SRM. METHODS AND RESULTS: SRM 3-5 cases (N = 505) and statin treatment-tolerant controls (N = 2047) were recruited from multiple sites in North America and Europe. SRM 3-5 was defined as symptoms consistent with muscle injury and an elevated creatine phosphokinase level >4 times upper limit of normal without another likely cause of muscle injury. Whole-exome sequencing and variant calling was coordinated from two analysis centres, and results of single-variant and gene-based burden tests were meta-analysed. No genome-wide significant associations were identified. Given the large number of cases, we had 80% power to identify a variant with minor allele frequency of 0.01 that increases the risk of SRM 6-fold at genome-wide significance. CONCLUSIONS: In this large whole-exome sequencing study of severe statin-related muscle injury conducted to date, we did not find evidence that rare coding variants are responsible for this adverse drug reaction. Larger sample sizes would be required to identify rare variants with small effects, but it is unclear whether such findings would be clinically actionable.

Fusidic Acid: A Neglected Risk Factor for Statin-Associated Myopathy.

BACKGROUND: Statins are widely used lipid-lowering drugs used for the prevention of cardiovascular disease. Statins are known to cause myopathy, an adverse drug reaction with various clinical features rhabdomyolysis. OBJECTIVE: To describe clinical characteristics of statin-treated individuals who experienced myopathy and identify risk factors of statin-associated myopathy. METHODS: A retrospective study was conducted on cases of statin-associated myopathy reported to the Swedish Medical Products Agency. Clinical factors were compared between cases and statin-treated controls not diagnosed with myopathy. Statistical methods were univariate and multivariate logistic regression and results were presented as odds ratio (OR) with 95% confidence interval (CI). To correct for multiple comparisons, the cutoff for statistical significance was set to P < .0017. RESULTS: In total, 47 cases of statin-associated myopathy were compared with 3871 treated controls. Rhabdomyolysis was diagnosed in 51% of the cases. Markers for cardiovascular disease were more common in cases than controls. Statistical analysis revealed the following independent risk factors for myopathy: high statin dose (OR = 1.54, calculated using the standard deviation 19.82, 95% CI = 1.32-1.80, P < .0001), and concomitant treatment with fusidic acid (OR = 1002, 95% CI = 54.55-18 410, P < .0001), cyclosporine (OR = 34.10, 95% CI = 4.43-262.45, P = .0007), and gemfibrozil (OR = 12.35, 95% CI = 2.38-64.10, P = .0028). CONCLUSIONS: The risk of myopathy increases with statin dose and cotreatment with cyclosporine and gemfibrozil. Concomitant fusidic acid has previously only been noted in a few case reports. Considering that use of fusidic acid may become more frequent, it is important to remind of this risk factor for statin-associated myopathy.

Clinical factors predicting drug-induced liver injury due to flucloxacillin.

OBJECTIVES: Drug-induced liver injury (DILI) is a serious adverse reaction due to flucloxacillin. The pathogenesis is not fully understood. Female sex, age over 60 years, and a longer treatment duration have been suggested to be predisposing factors. Carriers of HLA-B*57:01 have an 80-fold increased risk, but due to the rarity of the reaction, testing of all patients is not cost-effective. We aimed to validate and detect clinical risk factors for flucloxacillin DILI. METHODS: Clinical characteristics of flucloxacillin-treated patients with (n=50) and without DILI (n=2,330) were compared in a retrospective case control study. Cases were recruited from the Swedish database of spontaneously reported adverse drug reactions. Treated controls were selected from the Swedish Twin Registry. Statistical comparisons were made using chi-squared test and logistic regression. The significance threshold was set to P<0.00357 to correct for multiple comparisons. Reliable variables were tested in a multiple regression model. RESULTS: DILI was associated with female sex, OR 2.79, 95% CI 1.50-5.17, P=0.0011, and with a history of kidney stones, OR 5.51, 95% CI 2.21-13.72, P=0.0003. Cases were younger than controls, OR per increase in years 0.91, 95% CI 0.88-0.94, P<0.0001, probably due to selection bias. No difference in treatment duration was detected, OR 1.03, 95% CI 0.98-1.08, P=0.1790. CONCLUSION: We established female sex as a risk factor for flucloxacillin-induced DILI, and a history of kidney stones was identified as a potential risk factor. Clinical risk factors for flucloxacillin-induced DILI could be used to indicate whom to test for HLA-B*57:01 before treatment.