Liver injury with novel oral anticoagulants: assessing post-marketing reports in the US Food and Drug Administration adverse event reporting system

Machine Learning to Predict Drug-Induced Liver Injury and Its Validation on Failed Drug Candidates in Development

Drug-induced liver injury (DILI) poses a significant challenge for the pharmaceutical industry and regulatory bodies. Despite extensive toxicological research aimed at mitigating DILI risk, the effectiveness of these techniques in predicting DILI in humans remains limited. Consequently, researchers have explored novel approaches and procedures to enhance the accuracy of DILI risk prediction for drug candidates under development. In this study, we leveraged a large human dataset to develop machine learning models for assessing DILI risk. The performance of these prediction models was rigorously evaluated using a 10-fold cross-validation approach and an external test set. Notably, the random forest (RF) and multilayer perceptron (MLP) models emerged as the most effective in predicting DILI. During cross-validation, RF achieved an average prediction accuracy of 0.631, while MLP achieved the highest Matthews Correlation Coefficient (MCC) of 0.245. To validate the models externally, we applied them to a set of drug candidates that had failed in clinical development due to hepatotoxicity. Both RF and MLP accurately predicted the toxic drug candidates in this external validation. Our findings suggest that in silico machine learning approaches hold promise for identifying DILI liabilities associated with drug candidates during development.

Comparators in Pharmacovigilance: A Quasi-Quantification Bias Analysis

BACKGROUND AND OBJECTIVE

It is unclear which comparator is the most appropriate for bias reduction in disproportionality analyses based on spontaneous reports. We conducted a quasi-quantitative bias analysis using two well-studied drug-event combinations to assess how different comparators influence the directionality of bias in pharmacovigilance.

METHODS

We used the US Food and Drug Administration Adverse Event Reporting System focusing on two drug-event combinations with a propensity for stimulated reporting: rivaroxaban and hepatotoxicity, and canagliflozin and acute kidney injury. We assessed the directionality of three disproportionality analysis estimates (reporting odds ratio, proportional reporting ratio, information component) using one unrestricted comparator (full data) and two restricted comparators (active comparator, active comparator with class exclusion). Analyses were conducted within two calendar time periods, defined based on external events (approval of direct oral anticoagulants, Food and Drug Administration safety warning on acute kidney injury with sodium-glucose cotransporter 2 inhibitors) hypothesized to alter reporting rates.

RESULTS

There were no false-positive signals for rivaroxaban and hepatotoxicity irrespective of the comparator. Restricting to the initial post-approval period led to false-positive signals, with restricted comparators performing worse. There were false-positive signals for canagliflozin and acute kidney injury, with restricted comparators performing better. Restricting to the period before the Food and Drug Administration warning weakened the false-positive signal for canagliflozin and acute kidney injury across comparators.

CONCLUSIONS

We could not identify a consistent and predictable pattern to the directionality of disproportionality analysis estimates with specific comparators. Calendar time-based restrictions anchored on relevant external events had a considerable impact.

Case report: Severe hepatopathy following rivaroxaban administration in a dog

Rivaroxaban, a specific factor Xa inhibitor and commonly utilized anticoagulant, has been known to cause hepatotoxicity and liver failure in humans. Although rivaroxaban is frequently used in veterinary medicine, hepatotoxicity has not been previously reported in dogs. The current case report describes a dog that developed severe hepatopathy following rivaroxaban administration for a large right pulmonary artery thrombus. An estimated 6-year-old spayed female mixed-breed dog developed anorexia and lethargy 9 days after rivaroxaban administration began. Subsequent labwork revealed severe hepatocellular hepatopathy, and rivaroxaban was discontinued. Additional diagnostics did not reveal an underlying etiology, although hepatic cytology could be consistent with a toxic injury. The hepatopathy and clinical signs improved after rivaroxaban was discontinued. The time to onset, type of hepatopathy, and time to resolution were all similar to those reported for human cases. This case provides precedence to advocate for improved and closer monitoring of dogs receiving factor Xa inhibitors. In cases of suspected hepatotoxicity with no other identifiable cause, a risk-benefit analysis should be performed, and discontinuation of rivaroxaban administration or alternative anticoagulant medications should be considered.

The Challenge of Anticoagulation in Liver Cirrhosis

Background

Advanced liver diseases are characterized by a number of changes in the hemostatic system. Due to the occurrence of bleeding events in patients with liver cirrhosis, there seems to be a hesitance to the administration of anticoagulant medications. This review summarizes challenges, recommendations, and current developments of anticoagulation in the cirrhotic patient.

Summary

The risk of thrombotic events in patients with liver cirrhosis is at least as high as in patients with healthy liver function if not even higher. Standard laboratory markers do not truly reflect the complexity of changes that take place in the coagulative system and therefore cannot be used as a reference for risk of thrombosis or hemorrhage. Potential options for anticoagulant therapy are heparins, vitamin K antagonists, and direct-acting oral anticoagulants which come with differences in safety, application, possible side effects, and data availability for the patient cohort.

Key Message

The administration of anticoagulation can be beneficial in patients with liver disease if the indication is present and bleeding prophylaxis has been established. Direct-acting oral anticoagulants appear to be a promising new approach with many improvements compared to conventional substances. Nevertheless, there is a need for further data and prospective trials on the use in patients with liver cirrhosis.

Liver injury in children: signal analysis of suspected drugs based on the food and drug administration adverse event reporting system

BACKGROUND

Evidence of drug-induced liver injury is abundant in adults but is lacking in children. Our aim was to identify suspected drug signals associated with pediatric liver injury.

METHODS

Hepatic adverse events (HAEs) among children reported in the Food and Drug Administration Adverse Event Reporting System were analyzed. A descriptive analysis was performed to summarize pediatric HAEs, and a disproportionality analysis was conducted by evaluating reporting odds ratios (RORs) and proportional reporting ratios to detect suspected drugs.

RESULTS

Here, 14,143 pediatric cases were reported, specifically 49.6% in males, 45.1% in females, and 5.2% unknown. Most patients (68.8%) were 6-18 years old. Hospitalization ranked first among definite outcomes (7,207 cases, 37.2%). In total, 264 disproportionate drug signals were identified. The top 10 drugs by the number of reports were paracetamol (1,365; ROR, 3.6; 95% confidence interval (CI), 3.4-3.8), methotrexate (878; ROR, 2.5; 95% CI, 2.3-2.7), vincristine (649; ROR, 3.0; 95% CI, 2.8-3.3), valproic acid (511; ROR, 3.2; 95% CI, 2.9-3.6), cyclophosphamide (490; ROR, 2.4; 95% CI, 2.2-2.6), tacrolimus (427; ROR, 2.4; 95% CI, 2.2-2.7), prednisone (416; ROR, 2.1; 95% CI, 1.9-2.3), prednisolone (401; ROR, 2.3; 95% CI, 2.1-2.5), etoposide (378; ROR, 2.3; 95% CI, 2.1-2.6), and cytarabine (344; ROR, 2.8; 95% CI, 2.5-3.2). After excluding validated hepatotoxic drugs, six were newly detected, specifically acetylcysteine, thiopental, temazepam, nefopam, primaquine, and pyrimethamine.

CONCLUSIONS

The hepatotoxic risk associated with 264 signals needs to be noted in practice. The causality of hepatotoxicity and mechanism among new signals should be verified with preclinical and clinical studies.

Analyzing adverse drug reaction using statistical and machine learning methods: A systematic review

BACKGROUND

Adverse drug reactions (ADRs) are unintended negative drug-induced responses. Determining the association between drugs and ADRs is crucial, and several methods have been proposed to demonstrate this association. This systematic review aimed to examine the analytical tools by considering original articles that utilized statistical and machine learning methods for detecting ADRs.

METHODS

A systematic literature review was conducted based on articles published between 2015 and 2020. The keywords used were statistical, machine learning, and deep learning methods for detecting ADR signals. The study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA) guidelines.

RESULTS

We reviewed 72 articles, of which 51 and 21 addressed statistical and machine learning methods, respectively. Electronic medical record (EMR) data were exclusively analyzed using the regression method. For FDA Adverse Event Reporting System (FAERS) data, components of the disproportionality method were preferable. DrugBank was the most used database for machine learning. Other methods accounted for the highest and supervised methods accounted for the second highest.

CONCLUSIONS

Using the 72 main articles, this review provides guidelines on which databases are frequently utilized and which analysis methods can be connected. For statistical analysis, >90% of the cases were analyzed by disproportionate or regression analysis with each spontaneous reporting system (SRS) data or electronic medical record (EMR) data; for machine learning research, however, there was a strong tendency to analyze various data combinations. Only half of the DrugBank database was occupied, and the k-nearest neighbor method accounted for the greatest proportion.

Drug-Drug Interactions of Direct Oral Anticoagulants (DOACs): From Pharmacological to Clinical Practice

The direct oral anticoagulants (DOACs), dabigatran, rivaroxaban, apixaban, and edoxaban, are becoming the most commonly prescribed drugs for preventing ischemic stroke in patients with non-valvular atrial fibrillation (NVAF) and for the treatment and prevention of venous thromboembolism (VTE). Rivaroxaban was also recently approved for the treatment of patients with a recent acute coronary syndrome (ACS). Their use demonstrated to have a favorable risk-benefit profile, with significant reductions in stroke, intracranial hemorrhage, and mortality compared to warfarin, but with increased gastrointestinal bleeding. Nevertheless, their safety profile is compromised in multimorbidity patients requiring contemporary administration of several drugs. Comorbidity and polypharmacy have a high prevalence in elderly patients, who are also more susceptible to bleeding events. The combination of multiple treatments can cause relevant drug–drug interactions (DDIs) by affecting the exposure or the pharmacological activities of DOACs. Although important differences of the pharmacokinetic (PK) properties can be observed between DOACs, all of them are substrate of P-glycoprotein (P-gp) and thus may interact with strong inducers or inhibitors of this drug transporter. On the contrary, rivaroxaban and, to a lower extent, apixaban, are also susceptible to drugs altering the cytochrome P450 isoenzyme (CYP) activities. In the present review, we summarize the potential DDI of DOACs with several classes of drugs that have been reported or have characteristics that may predict clinically significant DDIs when administered together with DOACs. Possible strategies, including dosage reduction, avoiding concomitant administration, or different time of treatment, will be also discussed to reduce the incidence of DDI with DOACs. Considering the available data from specific clinical trials or registries analysis, the use of DOACs is associated with fewer clinically relevant DDIs than warfarin, and their use represents an acceptable clinical choice. Nevertheless, DDIs can be significant in certain patient conditions so a careful evaluation should be made before prescribing a specific DOAC.

Systemic quinolones and risk of retinal detachment III: a nested case-control study using a US electronic health records database

Background

Quinolones are popular antibiotics that are known for their potency, broad coverage, and reasonable safety. Concerns have been raised about a possible association between quinolones and retinal detachment (RD).

Methods

We conducted a nested case–control study using electronic health records (EHR) from the Health Facts® Database. The initial cohort included all patients who were admitted between 2000 and 2016, with no history of eye disease, and had a minimum medical history of one year. Eligible cases comprised inpatients who were first admitted with a primary diagnosis of RD between 2010 and 2015. Each eligible case was matched without replacement to five unique controls by sex, race, age, and period-at-risk. We used conditional logistic regression to calculate RD risk, adjusting for exposure to other medications, and major risk factors.

Results

We identified 772 cases and 3860 controls. Whereas our primary analysis of all subjects revealed no quinolone-associated RD risk, elevated but non-significant risks were noted in African Americans (ciprofloxacin and levofloxacin), those aged 56–70 years old (moxifloxacin), and women (ciprofloxacin).

Conclusion

Our study did not identify an elevated RD risk within 30 days following systemic administration of quinolone antibiotics. Suggestions of increased risk observed in some population subgroups warrant further investigation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00228-021-03260-4.

Drug interactions of direct oral anticoagulants in elderly patients with cardiometabolic diseases

In the present review we summarized current knowledge about significant interactions (DIs) of direct oral anticoagulants (DOACs) with other medications frequently prescribed to elderly patients with cardiometabolic diseases.

Literature search was performed using PubMed from 1990 to October 2020. Randomized clinical trials (RCTs), subgroup analyses from RCTs, longitudinal studies, case series and case reports were included. Only studies in humans were considered. Elderly was defined as ≥75 years.

Assessment of DIs with DOACs is often tricky because of the lack of validated tools to routinely assess magnitude of their anti-coagulation effect. Most of reports in the cardiometabolic area regarded the classes of anti-antiarrhythmic, lipid-lowering and platelet-inhibitors drugs, namely drugs that are widely used to reduce cardiovascular risk in patients with common metabolic diseases. Reports about elderly are limited in general, and it is not known whether certain types of DIs occur more frequently in elderly subjects. DIs were more frequently reported in association with dabigatran, which however has been available for a longer period of time compared with other DOACs. In most cases, no complete information about dosages of medications was available. DIs of DOACs leading to adverse events (both ischemic and bleeding ones) were generally facilitated by older age, polymedication and impaired renal function.

Further studies should be carried out to properly investigate DIs of DOACs with cardiometabolic drugs in elderly patients, with particular focus on differences between DOACs and the influence of different dosages.

Systemic quinolones and risk of retinal detachment I: analysis of data from the US FDA adverse event reporting system

BACKGROUND

Quinolones comprise a class of antibiotics that are globally preferred for treating a wide range of bacterial infections due to their potency, broad coverage, favorable pharmacologic profile, and mostly mild to moderate adverse reactions. Spontaneous reports on adverse drug events (ADE) and data from some pharmacoepidemiologic studies have raised concerns regarding quinolones and risk of retinal detachment (RD). This study examined ADE reports submitted to FDA adverse event reporting system (FAERS) for evidence on quinolone-associated RD risk.

RESEARCH DESIGN AND METHODS

We identified all RD reports in FAERS between 2010-2019. We compared ADE signals between quinolones and selected medications that were previously associated with RD, and with reference medications not known to cause RD. For signal detection, we used two techniques: the proportional reporting ratio (PRR) and multi-item gamma Poisson shrinker (MGPS), which are known for their higher sensitivity and specificity for ADE signal detection, respectively.

RESULTS

Moxifloxacin showed a positive and significant PRR signal for RD [PRR: 2.54 (1.60, 4.04)], and a marginally significant EBGM signal [EBGM: 2.21 (1.41, 3.02)].

CONCLUSION

Moxifloxacin is the only quinolone showing a positive disproportionality signal for RD. Further epidemiologic research is needed to clarify the association between moxifloxacin and RD risk.

Liver Injury Among Japanese Patients Treated Using Prophylactic Enoxaparin After Colorectal Surgery

BACKGROUND

Enoxaparin, a low molecular weight heparin, has been used to prevent thrombotic events during major surgery without increasing the rate of hemorrhage. On the other hand, it was reported to cause liver injury, but the details of liver injury induced by prophylactic enoxaparin after abdominal surgery remain unclear.

AIMS

This study aimed to clarify the relationship between prophylactic enoxaparin and liver injury after colorectal surgery, and characterize the injury profile.

METHODS

We retrospectively reviewed 732 Japanese patients who underwent elective resection of the colorectum, and compared their clinicopathological background, details of surgery, postoperative complications, including liver injury, and the type of liver injury according to prophylactic use of enoxaparin. Univariate and multivariate analyses were performed to identify risk factors for liver injury during the postoperative period.

RESULTS

The rate of liver injury was 8.9% for patients treated by prophylactic enoxaparin and 1.4% for those who did not receive enoxaparin after colorectal surgery (p < 0.0001). The median onset of liver injury among patients receiving enoxaparin was seven days, and the majority demonstrated the hepatocellular pattern. Enoxaparin was one of the independent risk factors for postoperative liver injury by multivariate analysis (odds ratio: 7.63, p < 0.0001).

CONCLUSIONS

Prophylactic use of enoxaparin markedly increased the rate of postoperative liver injury in patients who underwent colorectal surgery. Our study confirmed that close monitoring of liver function parameters is essential for patients receiving enoxaparin during the postoperative period.

Systemic quinolones and risk of acute liver failure I: Analysis of data from the US FDA adverse event reporting system

Background and Aim

Quinolones are a potent and globally popular group of antibiotics that are used to treat a wide range of infections. Some case reports have raised concern about their possible association with acute hepatic failure (AHF). Data from the US FDA Adverse Event Reporting System were evaluated for signals of AHF in association with systemically administered quinolone antibiotics.

Methods

AHF reports between 1969 and 2019q2, with a focus on 2010–2019q2, were analyzed. Specifically, AHF reports linked to non‐quinolone antibiotics of known hepatotoxicity were compared to reports with non‐quinolone, non‐hepatotoxic (reference) antibiotics; and AHF reports with quinolones were also compared to reports with the same group of reference antibiotics. Two disproportionality signal detection techniques (proportional reporting ratio, PRR, and empirical Bayes geometric mean, EBGM) were used to assess the AHF signal for both analyses.

Results

Only ciprofloxacin showed a marginal and significant AHF signal (PRR: 1.85 [1.21, 2.81]; EBGM: 1.54 [1.06, 1.81]); moxifloxacin, levofloxacin, and ofloxacin showed weak and nonsignificant signals.

Conclusion

Further pharmacovigilance studies are required to confirm the association between ciprofloxacin and AHF seen in the present analysis.

Acute liver failure after changing oral anticoagulant from apixaban to rivaroxaban

Rivaroxaban is a commonly used anticoagulant agent for treatment and prevention of thromboembolism. There are case reports demonstrating an association between its use and drug-induced liver injury. However, this has not been reported in a patient who previously tolerated apixaban. An 88-year-old man presented to hospital with worsening lethargy, jaundice and vomiting. He had severely elevated liver transaminases, an abnormal coagulation profile and elevated bilirubin in keeping with acute liver injury. This is in the context of having had his anticoagulation medication switched from apixaban to rivaroxaban 2 weeks prior. The patient recovered well after cessation of rivaroxaban, suggesting that it was the likely offending agent. The mechanism of rivaroxaban-induced liver injury remains to be investigated. Drug-induced liver injury should be discussed and monitored for as a potential adverse reaction when commencing rivaroxaban, even if a patient has previously tolerated a drug of the same class.

Update on drug interactions with non-vitamin-K-antagonist oral anticoagulants for stroke prevention in elderly patients

Introduction: We update the knowledge, since the last review in 2017, about drug-drug interactions (DDI) of non-vitamin-K-antagonist oral anticoagulants (NOAC) in patients ≥75 years.Areas covered: The literature was searched for: 'dabigatran,' 'rivaroxaban,' 'edoxaban,' or 'apixaban' and drugs, affecting platelet function, CYP3A4-, CYP2C9-, or P-Gp-activity. Pharmacodynamic DDI of NOAC with drugs affecting platelet function like nonsteroidal anti-inflammatory drugs and antiplatelet agents occur most frequently. Pharmacokinetic DDI with NOAC were found for 37 of 117 drugs. Reports about DDI with NOAC were found for 51% of P-gp-affecting, 38% for CYP2C9-affecting and 27% for CYP3A4-affecting drugs. Reports about DDI of cardiovascular drugs with NOAC were the most prevalent, followed by anti-infective and nervous system drugs. NOAC plasma levels were measured in retrospective and cohort studies and were associated with concomitant medication. Reports about DDI of NOAC were found in 71 patients ≥75 years.Expert opinion: The knowledge about DDI of NOAC in elderly patients is very limited. Studies should be carried out to investigate the role of drugs potentially interacting with NOAC, which until now have not been investigated. When studying DDI of NOAC, care should be taken to include elderly patients with impaired renal function and patients on polymedication.

Drug-Drug Interactions Leading to Adverse Drug Reactions with Rivaroxaban: A Systematic Review of the Literature and Analysis of VigiBase

Rivaroxaban has become an alternative to vitamin K antagonists, which are considered to be at higher risk of drug-drug interactions (DDI) and more difficult to use. However, DDI do occur. We systematically reviewed studies that evaluated them and analysed DDI and subsequent adverse drug reactions (ADR) reported in spontaneous reports and VigiBase. We systematically searched articles that explored DDI with rivaroxaban up to 20 August 2018 via Medline, Embase and Google Scholar. Data from VigiBase came from spontaneous reports recovered up to 2 January 2018, where Omega was used to detect signals and identify potential interactions in terms of triplets with two drugs and one ADR. We identified 31 studies and 28 case reports. Studies showed significant variation in the pharmacokinetic for rivaroxaban, and an increased risk of haemorrhage or thromboembolic events due to DDI was highlighted in case reports. From VigiBase, a total of 21,261 triplets were analysed and the most reported was rivaroxaban–aspirin–gastrointestinal haemorrhage. In VigiBase, only 34.8% of the DDI reported were described or understood, and most were pharmacodynamic DDI. These data suggest that rivaroxaban should be considered to have significant potential for DDI, especially with CYP3A/P-gp modulators or with drugs that impair haemostasis.

Adverse drug reactions with oral anticoagulants: data from sicilian spontaneous reporting system database

OBJECTIVE

Direct oral anticoagulants (DOACs) were developed to avoid the limitations of vitamin K antagonists (VKAs). DOACs are associated with a greater incidence of gastrointestinal bleeding and a smaller number of intracranial haemorrhages than VKAs. Therefore, it is important to deepen our knowledge of their safety profiles. The aim of this study was thus to analyse adverse drug reaction (ADR) reports on DOACs and VKAs using the Sicilian Spontaneous Reporting System (SRS) database.

METHODS

All ADR reports with DOACs and VKAs as suspected drugs that were entered into the Sicilian SRS database during the period 2001-2019 were selected. In detail, all reports with the following single active substances were included: dabigatran etexilate, rivaroxaban, apixaban and edoxaban; acenocoumarol and warfarin were included as a comparator group. Descriptive statistical methodology was used to evaluate characteristics of the reported cases with a case-by-case assessment.

RESULTS AND DISCUSSION

Out of 521 reports related to anticoagulants, 444 (85.2%) and 77 (14.8%) involved DOACs and VKAs, respectively. DOAC-related reports were mainly of gastrointestinal disorders. In contrast, VKAs were mostly associated with blood and lymphatic system disorders, injury, investigations and vascular disorders. Many more cases of ADRs in the form of gastrointestinal disorders concerned dabigatran etexilate (n = 179, 73.7%) than the other DOACs, while ADRs in the form of blood disorders were mainly associated with acenocoumarol (n = 27, 57.4%). The most commonly reported Preferred Terms for DOACs were dyspepsia (n = 89, 17.1%), upper abdominal pain (n = 41, 9.2%) and pruritus (n = 26, 5.8%), whereas for VKAs, they were anaemia (n = 21, 27.3%) and hypocoagulable state (n = 18, 3.5%). Potentially interacting concomitant medications particularly included antithrombotic agents (n = 19, 4.3%) for DOACs and proton-pump inhibitors (PPIs) (n = 37, 48.1%) and antithrombotic agents (n = 13, 16.9%) for VKAs.

CONCLUSION

The ADRs most commonly associated with DOACs, especially dabigatran, were gastrointestinal disorders, particularly gastrointestinal bleeding. Our study also highlights the potential role of drug-drug interactions in the ADRs. The cases of gastrointestinal bleeding highlight the need for careful prescribing of DOACs and use of potentially interacting concomitant drugs.

Nontumoral Portal Vein Thrombosis: A Challenging Consequence of Liver Cirrhosis

Nontumoral portal vein thrombosis (PVT) is an increasingly recognized complication in patients with cirrhosis. Substantial evidence shows that portal flow stasis, complex thrombophilic disorders, and exogenous factors leading to endothelial dysfunction have emerged as key factors in the pathogenesis of PVT. The contribution of PVT to hepatic decompensation and mortality in cirrhosis is debatable; however, the presence of an advanced PVT increases operative complexity and decreases survival after transplantation. The therapeutic decision for PVT is often determined by the duration and extent of thrombosis, the presence of symptoms, and liver transplant eligibility. Evidence from several cohorts has demonstrated that anticoagulation treatment with vitamin K antagonist or low molecular weight heparin can achieve recanalization of the portal vein, which is associated with a reduction in portal hypertension-related events and improved survival in cirrhotic patients with PVT. Consequently, interest in direct oral anticoagulants for PVT is increasing, but clinical data in cirrhosis are limited. Although the most feared consequence of anticoagulation is bleeding, most studies indicate that anticoagulation therapy for PVT in cirrhosis appears relatively safe. Interestingly, the data showed that transjugular intrahepatic portosystemic shunt represents an effective adjunctive therapy for PVT in cirrhotic patients with symptomatic portal hypertension if anticoagulation is ineffective. Insufficient evidence regarding the optimal timing, modality, and duration of therapy makes nontumoral PVT a challenging consequence of cirrhosis. In this review, we summarize the current literature and provide a potential algorithm for the management of PVT in patients with cirrhosis.

Drug-Drug Interactions between Direct Oral Anticoagulants and Hepatitis C Direct-Acting Antiviral Agents: Looking for Evidence Through a Systematic Review

Background

Direct oral anticoagulants (DOACs), as substrates of cytochrome P450 (CYP) 3A4 and/or P-glycoprotein, are susceptible to drug–drug interactions (DDIs). Hepatitis C direct-acting antiviral agents (DAAs), via P-glycoprotein or CYP3A4 inhibition, may increase DOAC exposure with relevant bleeding risk. We performed a systematic review on DDIs between DOACs and DAAs.

Methods

Two reviewers independently identified studies through electronic databases, until 7 July 2020, supplementing the search by reviewing conference abstracts and the ClinicalTrials.gov website.

Results

Of 1386 identified references, four articles were finally included after applying the exclusion criteria. Three phase I clinical studies in healthy volunteers assessed interactions between dabigatran and glecaprevir/pibrentasvir, odalasvir/simeprevir, or sofosbuvir/velpatasvir/voxilaprevir, showing an increase in the dabigatran area under the concentration–time curve (AUC) by 138%, 103%, and 161%, respectively.

Conclusions

DOACs and DAAs are under-investigated for DDI risk. Real-world studies are needed to assess the clinical relevance of the pharmacokinetic interactions with dabigatran and describe the actual spectrum of possible DDIs between DAAs and other DOACs.

Liver injury caused by oral anticoagulants: A population-based retrospective cohort study

BACKGROUND & AIMS

Idiosyncratic drug-induced liver injury (DILI) is a rare adverse event. DILI caused by direct oral anticoagulants (DOACs) has been reported, however, data on the risk of DILI are limited. The aim of the study was to evaluate the frequency of DILI caused by oral anticoagulants (OACs) in a population-based setting.

METHODS

A computerized database search in The National Prescription Database was performed identifying all patients in Iceland who were prescribed OACs (rivaroxaban, apixaban, dabigatran, edoxaban or warfarin) in 2008-2017. Personal identification numbers of these patients were linked with a database containing laboratory results for all hospitals and most outpatient clinics in Iceland. A medical chart review was performed in all cases where onset of liver injury followed intake of OACs. Patients with other specific causes of liver injury were excluded. Causality assessment with the RUCAM method was undertaken in cases with suspected DILI.

RESULTS

Three cases of suspected DILI were identified. In all cases, rivaroxaban was the implicated agent among patients prescribed this product (n = 3446). All were women with a hepatocellular type of liver injury. One patient developed a suspected drug-induced autoimmune hepatitis and was treated with corticosteroids. No cases of DILI in patients on warfarin (n = 9101), apixaban (n = 1903), dabigatran (n = 1335) and edoxaban (n = 34) were identified.

CONCLUSIONS

Rivaroxaban was the only OAC associated with DILI during the 10-year study period. Approximately 1 in 1100 patients treated with rivaroxaban developed DILI. Other OACs were not associated with liver injury in this population-based study.

Oral anticoagulants and risk of acute liver injury in patients with nonvalvular atrial fibrillation: a propensity-weighted nationwide cohort study

Insufficient real-world data on acute liver injury (ALI) risk associated with oral anticoagulants (OACs) exist in patients with nonvalvular atrial fibrillation (NVAF). Using the French national healthcare databases, a propensity-weighted nationwide cohort study was performed in NVAF patients initiating OACs from 2011 to 2016, considering separately those (1) with no prior liver disease (PLD) as main population, (2) with PLD, (3) with a history of chronic alcoholism. A Cox proportional hazards model was used to estimate the hazard ratio with 95% confidence interval (HR [95% CI]) of serious ALI (hospitalised ALI or liver transplantation) during the first year of treatment, for each non-vitamin K antagonist (VKA) oral anticoagulant (NOAC: dabigatran, rivaroxaban, apixaban) versus VKA. In patients with no PLD (N = 434,015), only rivaroxaban new users were at increased risk of serious ALI compared to VKA initiation (adjusted HR: 1.41 [1.05–1.91]). In patients with chronic alcoholism history (N = 13,173), only those initiating dabigatran were at increased risk of serious ALI compared to VKA (2.88 [1.74–4.76]) but an ancillary outcome suggested that differential clinical follow-up between groups might partly explain this association. In conclusion, this study does not suggest an increase of the 1-year risk of ALI in NOAC versus VKA patients with AF.

Real-world use of nonvitamin K antagonist oral anticoagulant in atrial fibrillation patients with liver disease: A meta-analysis

Several studies have investigated the effectiveness and safety of nonvitamin K antagonist oral anticoagulants (NOACs) vs vitamin K antagonists (VKAs) in patients with atrial fibrillation (AF) and liver disease. Herein, we conducted a meta‐analysis to compare the effect of NOACs with VKAs in patients with AF and liver disease. We also conducted a subsidiary analysis to compare the risk of liver injury between NOACs and VKA in AF patients. We systematically searched the PubMed and Embase databases from January 2009 to May 2020 for the relevant studies. Hazard ratios (HRs) with 95% confidence intervals (CIs) were selected and pooled using a random‐effects model. A total of six cohorts were included. Compared with VKA use, the use of NOACs was associated with reduced risks of stroke or systemic embolism (HR 0.68, 95% CI 0.49‐0.93), all‐cause death (HR 0.69, 95% CI 0.63‐0.75), and intracranial bleeding (HR 0.49, 95% CI 0.40‐0.59), whereas the outcomes of major bleeding (HR 0.72, 95% CI 0.51‐1.01) and gastrointestinal bleeding (HR 0.84, 95% CI 0.51‐1.36) were not significantly different between groups in AF patients with liver disease. Moreover, compared with VKA use, the use of NOACs was associated with a reduced risk of liver injury (HR 0.72, 95% CI 0.61‐0.84) in AF patients. Compared with VKAs, the use of NOACs was associated with reduced risks of stroke or systemic embolism, all‐cause death, and intracranial bleeding in AF patients with liver disease, and associated with a reduced risk of liver injury in AF patients.

Association between oral anticoagulants and osteoporosis: Real-world data mining using a multi-methodological approach

Introduction: Warfarin and direct oral anticoagulants (DOACs) have been widely used in antithrombotic therapy. Although warfarin use has been suspected to be associated with osteoporosis risk, several studies have shown otherwise. Conversely, a few reports have found an association between DOACs and osteoporosis. This study therefore clarifies the association between oral anticoagulants and osteoporosis by analyzing real-world data using different methodologies, algorithms, and databases. Methods: Real-world data from the US Food and Drug Administration Adverse Event Reporting System (FAERS; 2004-2016) and Japanese administrative claims database (2005-2017; JMDC Inc., Tokyo) were used. Reporting odds ratio (ROR) and information component (IC) were calculated through disproportionality analysis (DPA) using reports recorded in the FAERS. Sequence symmetry analysis (SSA) was employed to calculate the adjusted sequence ratio (SR) using the JMDC Claims Database. For the adjusted SR and ROR, a significant signal was detected when the lower limit of the two-sided 95% confidence interval (CI) was more than 1. For the IC, a significant signal was detected when the lower limit of the 95% CI was more than 0. Results: DPA for warfarin found significant signals for osteoporosis in ROR (1.43, 95% CI: 1.32-1.54) and IC (0.50, 95% CI: 0.39-0.61). SSA showed a significant association between warfarin use and osteoporosis or bisphosphonate use. Moreover, a significant association was observed in males and females, albeit only for warfarin. Conclusion: Multi-methodological data mining revealed that warfarin use, not DOACs, is significantly associated with osteoporosis regardless of sex difference.

Non-Vitamin K Antagonist Oral Anticoagulants and Risk of Serious Liver Injury

BACKGROUND

Non-vitamin K antagonist oral anticoagulants (NOACs) are relatively new drugs used for stroke prevention in nonvalvular atrial fibrillation (NVAF). However, there are concerns that their use may be associated with hepatotoxic effects.

OBJECTIVES

The purpose of this study was to determine whether the use of NOACs is associated with an increased risk of serious liver injury compared with the use of vitamin K antagonists (VKAs) in NVAF patients with and without prior liver disease.

METHODS

Using the administrative databases of the Canadian province of Quebec's health insurances, the authors conducted a cohort study among patients newly diagnosed with NVAF between January 2011 and December 2014. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of serious liver injury (defined as either a hospitalization or related death) were estimated using time-dependent Cox proportional hazards models, comparing current use of NOACs to current use of VKAs separately among patients with or without prior liver disease.

RESULTS

The cohort comprised 51,887 patients, including 3,778 with prior liver disease. During 68,739 person-years of follow-up, 585 patients experienced a serious liver injury. Compared with current use of VKAs, current use of NOACs was not associated with an increased risk of serious liver injury in patients without or with prior liver disease (adjusted HR: 0.99; 95% CI: 0.68 to 1.45; and adjusted HR: 0.68; 95% CI: 0.33 to 1.37, respectively).

CONCLUSIONS

Compared with VKAs, NOACs were not associated with an increased risk of serious liver injury irrespective of baseline liver status. Overall, these results provide reassurance regarding the hepatic safety of NOACs.

Direct Oral Anticoagulants in Chronic Liver Disease

Objective: To review the use of direct oral anticoagulants (DOACs) in patients with chronic liver disease (CLD). Data Sources: A MEDLINE literature search was performed from 1964 through February 2019 using the following search terms: cirrhosis, chronic liver disease, direct oral anticoagulant, and the individual DOACs. Study Selection and Data Extraction: All English-language human trials and reports that examined DOACs for treatment or prevention of venous thromboembolic (VTE) events in patients with CLD were included. Data Synthesis: A total of 6 clinical trials examining the use of DOACs in patients with CLD were identified. All DOACs have been utilized in patients with CLD, with the exception of betrixaban, for prevention of stroke in atrial fibrillation or treatment of VTE (except for treatment of pulmonary embolism). The studies primarily evaluated patients with mild to moderate liver disease (Child-Turcotte-Pugh class A and B). The DOACs had similar rates of bleeding compared with traditional anticoagulants. Relevance to Patient Care and Clinical Practice: This review evaluates and summarizes the available evidence on DOACs in the setting of CLD. These agents may be more appealing in this population because monitoring or administration may be difficult with traditional anticoagulants (warfarin or low-molecular-weight heparins). Conclusion: Early data suggest that DOACs may be safe in patients with mild to moderate CLD. Should a DOAC be selected as an alternative to traditional anticoagulants, more frequent monitoring should be used because hepatotoxicity may be a concern. Larger clinical trials are needed to address efficacy outcomes as well as differences among individual DOACs in this population.

Non-bleeding Adverse Events with the Use of Direct Oral Anticoagulants: A Sequence Symmetry Analysis

Introduction

Postmarketing pharmacovigilance reports have raised concerns about non-bleeding adverse events associated with direct oral anticoagulants (DOACs), but only limited results are available from large claims databases.

Objective

The aim of this study was to assess the potential association between DOAC initiation and the onset of four types of non-bleeding adverse events by sequence symmetry analysis (SSA).

Methods

SSA was performed using nationwide data from the French National Healthcare databases (Régime Général, 50 million beneficiaries) to assess a cohort of 386,081 DOAC new users for the first occurrence of four types of non-bleeding outcomes: renal, hepatic, skin outcomes identified by using hospitalization discharge diagnoses, and gastrointestinal outcomes by using medication reimbursement. Asymmetry in the distribution of each investigated outcome occurring before and after initiation of DOAC therapy was used to test the association between DOAC therapy and these outcomes. SSA inherently controls for time-constant confounders, and adjusted sequence ratios were computed after correcting for temporal trends. Negative (glaucoma) and positive (bleeding, depressive disorders) control outcomes were used and analyses were replicated on a cohort of 310,195 patients initiating a vitamin K antagonist (VKA).

Results

This study demonstrated the expected positive association between either DOAC or VKA therapy and hospitalised bleeding and initiation of antidepressant therapy, while no association was observed between either DOAC or VKA therapy and initiation of antiglaucoma medications. For DOAC therapy, signals were the associations with hepatic outcomes, including acute liver injury [for the 3-month time window, aSR₃ = 2.71, 95% confidence interval (CI) 1.79–4.52]; gastrointestinal outcomes, including initiation of drugs for constipation and antiemetic drugs (aSR₃ = 1.31, 95% CI 1.27–1.36; and 1.17, 95% CI 1.12–1.22, respectively); and kidney diseases (aSR₃ = 1.33, 95% CI 1.29–1.37).

Conclusion

Results of this nationwide study suggest that DOACs are associated with rare but severe liver injury and more frequent gastrointestinal disorders. A low risk of kidney injury with DOAC therapy can also not be excluded.

Electronic supplementary material

The online version of this article (10.1007/s40264-018-0668-9) contains supplementary material, which is available to authorized users.

Liver injury with drugs used for multiple sclerosis: A contemporary analysis of the FDA Adverse Event Reporting System

Background:

Drug-induced liver injury (DILI) has been observed in patients with multiple sclerosis (MS), raising concerns on the liver safety of MS drugs.

Objective:

To describe DILI events with MS drugs by analyzing the FDA Adverse Event Reporting System.

Methods:

DILI reports were extracted and classified in overall liver injury (OLI), including asymptomatic elevation of liver enzymes, and severe liver injury (SLI). We performed disproportionality analysis by calculating adjusted reporting odds ratios (RORs) with 95% confidence interval (CI) and case-by-case evaluation for concomitant drugs with hepatotoxic potential.

Results:

Fampridine showed statistically significant ROR for both OLI and SLI, whereas teriflunomide and fingolimod generated solid disproportionality (ROR > 2) only for OLI (ROR, 2.31; 95% CI, 2.12–2.52; and 2.53; 2.40–2.66, respectively). Among monoclonal antibodies, only alemtuzumab generated higher-than-expected ROR for OLI (1.34; 1.09–1.65). We also detected the expected hepatotoxic potential of beta interferon and mitoxantrone. Concomitant reporting of hepatotoxic drugs ranged from 26% (dimethyl fumarate) to 90% (mitoxantrone).

Conclusion:

These real-world pharmacovigilance findings suggest that DILI might be a common feature of MS drugs and call for (1) formal population-based study to verify the risk of fampridine and (2) awareness by clinicians, who should assess the possible responsibility of MS drugs when they diagnose DILI.

Cognition- and Dementia-Related Adverse Effects With Sacubitril-Valsartan: Analysis of the FDA Adverse Event Report System Database

BACKGROUND

Because neprilysin is involved in the degradation of amyloid-beta, there is concern that the angiotensin-neprilysin inhibitor sacubitril-valsartan could increase the risk for dementia.

METHODS

We analyzed adverse event cases submitted to the Food and Drug Administration Adverse Event Report System from July 2015 to March 2017. Cognition- and dementia-related adverse event cases were defined with the use of broad and narrow structured medical queries.

RESULTS

During the period evaluated, 9,004 adverse event reports (out of a total of 2,249,479) involved the use of sacubitril-valsartan. Based on the broad definition, sacubitril-valsartan was associated with cognition- and dementia-related adverse events in 459 reports (5.1%), but this was lower than the proportion of these reports among other medications (6.6%, reporting odds ratio [ROR] 0.72, 95% confidence interval [CI] 0.65-0.79). Restricting the comparison to cases with age >60 years and with the use of a comparator group with heart failure resulted in no association between sacubitril-valsartan and dementia-related adverse events, with the use of both the broad and the narrow definitions (ROR 0.87, 95% CI 0.76-1.02, and ROR 1.06, 95% CI 0.4-3.16, respectively).

CONCLUSION

Sacubitril-valsartan is not associated with a disproportionately high rate of short-term dementia-related adverse effect reports. Long-term studies assessing cognitive outcomes are required to better establish the medication's cognition effects.

WITHDRAWN: Cognition and Dementia Related Adverse Effects with Sacubitril-Valsartan: Analysis of the FDA Adverse Event Report System Database

The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org/10.1016/j.cardfail.2018.04.009. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

Regulation of Organic Anion Transporting Polypeptides (OATP) 1B1- and OATP1B3-Mediated Transport: An Updated Review in the Context of OATP-Mediated Drug-Drug Interactions

Organic anion transporting polypeptides (OATP) 1B1 and OATP1B3 are important hepatic transporters that mediate the uptake of many clinically important drugs, including statins from the blood into the liver. Reduced transport function of OATP1B1 and OATP1B3 can lead to clinically relevant drug-drug interactions (DDIs). Considering the importance of OATP1B1 and OATP1B3 in hepatic drug disposition, substantial efforts have been given on evaluating OATP1B1/1B3-mediated DDIs in order to avoid unwanted adverse effects of drugs that are OATP substrates due to their altered pharmacokinetics. Growing evidences suggest that the transport function of OATP1B1 and OATP1B3 can be regulated at various levels such as genetic variation, transcriptional and post-translational regulation. The present review summarizes the up to date information on the regulation of OATP1B1 and OATP1B3 transport function at different levels with a focus on potential impact on OATP-mediated DDIs.

Rivaroxaban-induced hepatotoxicity: review of the literature and report of new cases

AIM/OBJECTIVE/BACKGROUND

Direct-acting oral anticoagulant drugs are marketed worldwide for the primary and secondary prevention and treatment of thromboembolic disorders. Rivaroxaban, an oral, direct factor Xa inhibitor, is one of the most used. Rivaroxaban-induced hepatotoxicity is unusual, although a number of adverse reports have recently been reported. Here, we report two new cases of rivaroxaban-induced hepatitis.

METHODS

A systematic search of case reports on the MEDLINE database encompassing the years 2008-2016 was carried out.Additional references were obtained following a manual search of the retrieved papers. We report two new cases of adverse events occurred in patients treated with rivaroxaban (20 mg/die) to prevent systemic embolism, who presented with hepatocellular liver injury with onset at 8 weeks after initiation of the drug intake.

RESULTS

Twenty-six cases were retrieved from MEDLINE (57.7% female, 42.3% male). Using the Roussel Uclaf Causality Assessment Method (RUCAM) scale, liver injury was classified as hepatocellular (42.3%), cholestatic (26.9%), or mixed (15.4%). Older age (≥65 years) was present as a risk factor in 57.7%. The time lapse between initiation of treatment and onset of hepatic injury ranged from 2 to 180 days (median: 15 days). Our two new patients were diagnosed with drug-induced liver injury (hepatocellular pattern) using the 'consensus criteria', for drug-induced liver injury. Their RUCAM scores were calculated and assessed as highly probable and probable, respectively. A clinical recovery after rivaroxaban withdrawal was observed.

CONCLUSION

Direct-acting oral anticoagulants have been commonly prescribed, even if safety issues regarding the use of these drugs are still an ongoing concern, especially in patients experiencing chronic liver disease. Dedicated postauthorization safety studies should be undertaken to better define rivaroxaban-induced drug-induced liver injury.

Hepatotoxicity associated with statins

Treatment with statins is known all over the world. They are generally considered safe at therapeutic doses. Nevertheless, clinical trials are not enough to assess their scarce adverse effects such as idiosyncratic drug induced liver injury (DILI). Due to some conditions, such as concomitant usage (drug-drug interaction using an identical metabolising enzyme) and genetic polymorphisms, there is an increasing concern about their safety. Hepatotoxicity and rhabdomyolysis have begun to appear in published studies. Most of investigations have focused on both these adverse effects and mechanisms of drug induced toxicity. The present review has attempted to compile almost all of the existing studies on the hepatotoxicity of statins but not rhabdomyolysis. The aim of our study is to provide an overview of the studies on the statin-associated hepatotoxicity and to discuss the published studies. The researchers are of the opinion that the research on this topic is incomplete but extremely necessary.

Non-hemorrhage-related adverse effects of rivaroxaban

The direct oral anticoagulant rivaroxaban is useful in various indications that include venous deep vein thrombosis prophylaxis/treatment after knee/hip replacement surgery and prevention of stroke in patients with non-valvular atrial fibrillation. Its mechanism of action has been mostly associated with hemorrhage-related adverse effects; thus a number of non-hemorrhage-related adverse effects of the drug have received less attention or go unrecognized. These adverse effects mainly include liver injury, hypersensitivity reactions, leukocytoclastic vasculitis and hair loss. Clinicians should be aware of these rare adverse reactions and advise their patients to contact them as soon as they observe any unexpected clinical response.

Acute renal failure with sodium-glucose-cotransporter-2 inhibitors: Analysis of the FDA adverse event report system database

BACKGROUND AND AIMS

Sodium-glucose-cotransporter-2 (SGLT2) inhibitors have recently been approved for the treatment of type II diabetes mellitus (T2DM). It has been proposed that these agents could induce acute renal failure (ARF) under certain conditions. This study aimed to evaluate the association between SGLT2-inhibitors and ARF in the FDA adverse event report system (FAERS) database.

METHODS AND RESULTS

We analyzed adverse event cases submitted to FAERS between January 2013 and September 2016. ARF cases were identified using a structured medical query. Medications were identified using both brand and generic names. During the period evaluated, 18,915 reports (out of a total of 3,832,015 registered in FAERS) involved the use of SGLT2-inhibitors. SGLT2-inhibitors were reportedly associated with ARF in 1224 of these cases (6.4%), and were defined as the "primary" or "secondary" cause of the adverse event in 96.8% of these cases. The proportion of reports with ARF among reports with SGLT2 inhibitor was almost three-fold higher compared to reports without these drugs (ROR 2.88, 95% CI 2.71-3.05, p < 0.001). The proportion of ARF reports among cases with SGLT2-inhibitors was significantly greater than the proportion of ARF among cases with T2DM without SGLT2-inhibitors (ROR 1.68, 95% CI 1.57-1.8, p < 0.001). Among the SGLT2-inhibitors, canagliflozin was associated with a higher proportion of reports of renal failure (7.3%), compared to empagliflozin and dapagliflozin (4.7% and 4.8% respectively, p < 0.001).

CONCLUSION

SGLT2-inhibitors are associated with an increase in the proportion of reports of ARF compared to other medications. SGLT2-inhibitor agents may differ from one another in their respective risk for ARF.

Rivaroxaban-Induced Hypersensitivity Syndrome

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Safety profile of the direct oral anticoagulants: an analysis of the WHO database of adverse drug reactions

AIM

Direct oral anticoagulants (DOACs) have shown noninferiority to warfarin for stroke prevention in nonvalvular atrial fibrillation (AF) and a more promising safety profile. Unanswered safety aspects remain to be addressed and available evidence on the risk associated with these drugs are conflicting. In order to contribute to the debate on their safety profile, we conducted a comparative analysis of the reports of suspected adverse drug reactions (ADRs) associated with DOACs in VigiBase.

METHODS

Study based on reports of suspected ADRs held in VigiBase as at December 2014, in which a DOAC or warfarin were administered in patients with nonvalvular AF and listed as suspected/interacting drugs. Medical Dictionary for Regulatory Activities was used to classify ADRs. Reporting odds ratio (ROR) with 95% confidence interval were calculated. Results with P ≤ 0.05 were statistically significant.

RESULTS

We retrieved 32 972 reports. We identified 204 ADRs with a ROR >1 (P ≤ 0.05) and we focused on 105 reactions. Positive ROR emerged for DOACs and gastrointestinal haemorrhage compared with warfarin [(1.6 (1.47-1.75)], but no disproportionality with cerebral haemorrhage was found [0.31 (0.28-0.34)]. We identified other potential signals that have not been associated with DOACs previously.

CONCLUSIONS

As well as premarketing authorization clinical trial studies, we found a reduced risk of intracranial haemorrhage, but an increased risk of gastrointestinal haemorrhage in patients treated with DOACs compared to warfarin. We provide new data and we highlight several differences between the three novel oral anticoagulants, in the rate and type of ADRs occurred.

Drug-Induced Liver Injury

Drug-induced liver injury (DILI) can result from both idiosyncratic and intrinsic mechanisms. This article discusses the clinical impact of DILI from a broad range of medications as well as herbal and dietary supplements. Risk factors for idiosyncratic DILI (IDILI) are the result of multiple host, environmental, and compound factors. Some triggers of IDILI often seen in critical care include antibiotics, antiepileptic medications, statins, novel anticoagulants, proton pump inhibitors, inhaled anesthetics, nonsteroidal anti-inflammatory agents, methotrexate, sulfasalazine, and azathioprine. The mechanism of IDILI due to these medications varies, and the resulting damage can be cholestatic, hepatocellular, or mixed. The primary treatment of IDILI is to discontinue the causative agent. DILI due to acetaminophen is intrinsic because the liver damage is predictably aligned with the dose ingested. Acute acetaminophen ingestion can be treated with activated charcoal or N-acetylcysteine. Future areas of research include identification of mitochondrial stress biomarkers and of the patients at highest risk for DILI.

Adverse drug reactions of botulinum neurotoxin type A in children with cerebral palsy: a pharmaco-epidemiological study in VigiBase

AIM

The aim of this study was to assess the risk of adverse drug reactions (ADRs) with botulinum neurotoxin type A (BoNT-A) in children with cerebral palsy (CP) using the World Health Organization global individual case safety report (ICSR) database, VigiBase.

METHOD

We extracted all children ICSRs for ADRs with BoNT-A used as anti-spastic drug in CP recorded between 1995 and 2015 in VigiBase. We also performed a case/non-case method (disproportionality analysis) to assess the link between exposure to BoNT-A and each ADR of interest in children and adults, calculating reporting odds ratios (RORs).

RESULTS

In VigiBase, 162 ICSRs were registered. They involved mainly males (n=95, 59%) and mean (SD) age was 7 years 11 months (4y 4mo). The most frequent ADR was dysphagia (27 ICSRs, 17%) followed by asthenia and muscular weakness (25 ICSRs each, 16%). Nineteen ICSRs (12%) were lethal. There was a significant association between BoNT-A and death in children (ROR=11.1 95%, confidence interval [CI] 7.0-17.7) but not in adults.

INTERPRETATION

In children with CP, most ADRs seem to be linked to a systemic spread of BoNT-A. Our study suggests a higher risk of ADRs with BoNT-A in children than in adults.

Drug Hepatotoxicity: Newer Agents

Idiosyncratic hepatotoxicity is one of the most common reasons for an approved drug being restricted. This article focuses on hepatotoxicity of selected and recently introduced agents, such as, tyrosine kinase inhibitors, monoclonal antibodies, novel oral anticoagulants, newer antiplatelets, antibiotics, anti-diabetics, anti-epileptics, anti-depressants, anti-psychotics and anti-retrovirals. Overall, the incidence of clinically relevant hepatotoxicity from newer agents seems to be lower than that of the older agents. Nevertheless, cases of severe hepatotoxicity have been reported due to some of these newer agents, including, trastuzumab, ipilimumab, infliximab, imatinib, bosutinib, dasatinib, gefitinib, erlotinib, sunitinib, ponatinib, lapatinib, vemurafenib, dabigatran, rivaroxaban, felbamate, lamotrigine, levetiracetam, venlafaxine, duloxetine, darunavir, and maraviroc.

Drug-induced liver injury: Towards early prediction and risk stratification

Drug-induced liver injury (DILI) is a hot topic for clinicians, academia, drug companies and regulators, as shown by the steadily increasing number of publications and agents listed as causing liver damage (http://livertox.nih.gov/). As it was the case in the past decade with drug-induced QT prolongation/arrhythmia, there is an urgent unmet clinical need to develop tools for risk assessment and stratification in clinical practice and, in parallel, to improve prediction of pre-clinical models to support regulatory steps and facilitate early detection of liver-specific adverse drug events. Although drug discontinuation and therapy reconciliation still remain the mainstay in patient management to minimize occurrence of DILI, especially acute liver failure events, different multidisciplinary attempts have been proposed in 2016 to predict and assess drug-related risk in individual patients; these promising, albeit preliminary, results strongly support the need to pursue this innovative pathway.

Risk-Benefit Profile of Direct-Acting Oral Anticoagulants in Established Therapeutic Indications: An Overview of Systematic Reviews and Observational Studies

Since 2008, the direct-acting oral anticoagulants (DOACs) have expanded the therapeutic options of cardiovascular diseases with recognized clinical and epidemiological impact, such as non-valvular atrial fibrillation (NVAF) and venous thromboembolism (VTE), and also in the preventive setting of orthopedic surgical patients. The large body of evidence, not only from pivotal clinical trials but also from 'real-world' postmarketing observational findings (e.g. analytical epidemiological studies and registry data) gathered to date allow for a first attempt at verifying a posteriori whether or not the pharmacological advantages of the DOACs actually translate into therapeutic innovation, with relevant implications for clinicians, regulators and patients. This review aims to synthesize the risk-benefit profile of DOACs in the aforementioned consolidated indications through an 'evidence summary' approach gathering the existent evidence-based data, particularly systematic reviews with meta-analyses of randomized controlled trials, as well as observational studies, comparing DOACs with vitamin K antagonists. Clinical evidence will be discussed and compared with major international guidelines to identify whether an update is needed. Controversial clinically relevant safety issues will be also examined in order to highlight current challenges and unsettled questions (e.g. actual bleeding risk in susceptible populations). It is anticipated that the large number of publications on NVAF or VTE (44 systematic reviews with meta-analyses and 12 observational studies retained in our analysis) suggests the potential existence of overlapping studies and calls for common criteria to qualitatively and quantitatively assess discordances, thus guiding future research.