Use of Hy's law and a new composite algorithm to predict acute liver failure in patients with drug-induced liver injury

EASL Clinical Practice Guidelines: Drug-induced liver injury

Idiosyncratic (unpredictable) drug-induced liver injury is one of the most challenging liver disorders faced by hepatologists, because of the myriad of drugs used in clinical practice, available herbs and dietary supplements with hepatotoxic potential, the ability of the condition to present with a variety of clinical and pathological phenotypes and the current absence of specific biomarkers. This makes the diagnosis of drug-induced liver injury an uncertain process, requiring a high degree of awareness of the condition and the careful exclusion of alternative aetiologies of liver disease. Idiosyncratic hepatotoxicity can be severe, leading to a particularly serious variety of acute liver failure for which no effective therapy has yet been developed. These Clinical Practice Guidelines summarize the available evidence on risk factors, diagnosis, management and risk minimization strategies for drug-induced liver jury.

ALK inhibition in two emblematic cases of pediatric inflammatory myofibroblastic tumor: Efficacy and side effects

There is an increasing interest for anaplastic lymphoma kinase (ALK) inhibitors in pediatric oncology for specific entities such as ALK-driven inflammatory myofibroblastic tumor (IMT). IMT treatment can be challenging due to localization of the tumor and in rare cases of metastasis. When standard surgical treatment is not feasible, ALK inhibitors may play an important role, as recently reported for the first-generation ALK inhibitors (crizotinib). However, data on the second-generation ALK inhibitors are limited. We report two emblematic cases of IMT in pediatric patients, treated with the second-generation ALK inhibitor ceritinib in the context of a clinical trial (NCT01742286).

Tools for causality assessment in drug-induced liver disease

PURPOSE OF REVIEW

There are three liver-specific causality assessment tools currently available to guide clinical diagnosis of Drug-Induced Liver Injury (DILI): Roussel-Uclaf Causality Assessment Method (RUCAM), Digestive-Disease-Week Japan 2004 scale (DDW-J), and Clinical Diagnostic Scale (CDS). The purpose of this review is to assess these tools and discuss how to improve the causality assessment process as a whole.

RECENT FINDINGS

Existing DILI-specific causality assessment tools are surprisingly similar and exhibit only minor differences in point allocation. But difference in threshold for likelihood of being DILI. We reviewed the literature on currently used causality assessment tools, identified areas for future improvement, and herein propose approaches for refinement. Opportunities to improve current models, as well as the assessment process, in general, include in particular provision of more precise clinical detail and to perhaps add new components to scoring systems. For example, the incorporation of drug-specific clinical signature patterns, accounting for a drug's inherent hepatotoxicity potential, and/or incorporation of other drug properties to scoring systems may allow enhancement. Further, more systemic exclusion of competing diagnoses is needed. Finally, causality assessment processes will likely benefit from a data-driven and computer-assisted approach.

SUMMARY

Current tools used for DILI adjudication are imperfect. Avenues to improve these tools are described.

Idiosyncratic drug-induced liver injury in patients: Detection, severity assessment, and regulatory implications

Idiosyncratic Drug-Induced Liver Injury (IDILI) is a rare but potentially life-threatening event that is caused by drugs that, at usual therapeutic doses, do not cause any biochemical or clinical evidence of liver injury in the majority of treated patients. The most common clinical phenotypes of IDILI are "acute hepatitis," "mixed hepatocellular-cholestatic hepatitis," and "cholestatic hepatitis" and these are distinguished by clinical, biochemical and histologic characteristics. Anti-microbials, herbals and dietary supplements are now the agents most often implicated in the US Drug-Induced Liver Injury Network registry. There are several scales that have been used to characterize the severity of IDILI events. There are no reliable means to accurately predict the course of an IDILI event at presentation. In clinical trials, the "gold standard" liver safety signal is the occurrence of "Hy's Law Cases." Making the diagnosis of IDILI, and when a patient is taking multiple drugs, identifying the most likely culprit can be challenging, but many drugs cause IDILI with characteristic clinical and biochemical presentations, or "signatures." In a clinical trial, it is sometimes possible to identify an overlooked "signature" of IDILI by characterizing more minor, asymptomatic, and transient elevations in liver chemistries. This observation can be helpful in assessing causation in rare serious liver events occurring in the clinical trial, or first recognized post-marketing.

A proposed pathologic sub-classification of drug-induced liver injury

BACKGROUND

The aim of this study was to establish a new pathologic sub-classification of drug-induced liver injury (DILI) in combination with serum chemistry parameters and clinical observations.

METHODS

From 777 DILI cases diagnosed in China-Japan Friendship Hospital from 2003 to 2014, 590 cases without other concomitant liver diseases were selected for the study. Pathological classification was established. Pathology and serum biochemical correlation analyses in 208 acute cases with complete biochemical data and prognostic information were conducted.

RESULTS

We established a pathological classification of DILI according to the target cells of the liver (hepatocytes, bile duct epithelial cells, liver vascular and sinusoidal endothelial cells). In the 590 cases of DILI analyzed, hepatocyte injury accounted for 67.0%, bile duct epithelial injury (including cholestasis and mixed type of injury) 23.9%, and vascular injury 8.8%; about half of them were caused by the administration of traditional Chinese herbal medicines. Acute hepatocyte injury (lobular hepatitis) is further divided into mild, moderate and severe subtypes, while the mixed type of injury is categorized as cholestatic hepatitis and mixed hepatitis. The dynamic liver enzyme curves were established between lobular hepatitis and mixed-type hepatitis based on the combined consideration of histopathology and serum chemistry data. We proved that R value > 5 with cholestasis is a special feature of mixed hepatitis, which clarified the suspicion of the previous clinical classification of R value. Greater attention should be paid to drug-induced bile duct vanishing syndrome and drug-induced vascular injury.

CONCLUSION

The pathological classification is simple to adopt and practically useful, which demonstrates the consistency between clinical features and liver pathology. The correlation between pathology and clinical biochemistry is an important way to acquire further understanding of DILI.

Drug-Induced Liver Injuries (Clinical Guidelines for Physicians)

Aim.Clinical guidelines for the management of adult patients suffering from drug-induced liver injuries (DILI) are intended for all medical specialists, who treat such patients in their clinical practice.

Key findings.The presented recommendations contain information about the epidemiological data, terminology, diagnostic principles, classification, prognosis and management of patients with DILI. The recommendations list pharmacological agents that most commonly cause DILI, including its fatal cases. Dose-dependent and predictable (hepatotoxic), as well as dose-independent and unpredictable (idiosyncratic) DILI forms are described in detail, which information has a particular practical significance. The criteria and types of DILI are described in detail, with the most reliable diagnostic and prognostic scales and indices being provided. The pathogenesis and risk factors for the development of DILI are considered. The clinical and morphological forms (phenotypes) of DILI are described. The diseases that are included into the differential diagnosis of DILI, as well as the principles of its implementation, are given. The role and significance of various diagnostic methods for examining a patient with suspected DILI is described, with the liver biopsy role being discussed. Clinical situations, in which DILI can acquire a chronic course, are described. A section on the assessment of causal relationships in the diagnosis of DILI is presented; the practical value of using the CIOMS-RUCAM scale is shown. All possible therapeutic measures and pharmacological approaches to the treatment of patients with various DILI phenotypes are investigated in detail. A particular attention is paid to the use of glucocorticosteroids in the treatment of DILI.

Conclusion.The presented clinical recommendations are important for improving the quality of medical care in the field of hepatology.

Liver injury after methylprednisolone pulses: A disputable cause of hepatotoxicity. A case series and literature review

Background and Objectives

Corticosteroids are often empirically used to treat idiosyncratic hepatotoxicity with severe features. Interestingly, intravenous methylprednisolone (MP) is increasingly being recognized as being responsible for liver injury. We aimed to characterize MP-induced liver injury by analyzing demographical, clinical, laboratory and outcome data of three MP-induced hepatotoxicity cases and compared this information with that of previously published cases.

Case series

Three females with multiple sclerosis (MS) were treated intravenously with MP, mean daily dose 767 mg. Liver damage occurred 2 to 6 weeks after exposure. Severity was mild to moderate. Two patients suffered positive rechallenge.

Literature review

We identified 50 published cases of MP hepatotoxicity. Most of these cases were female (86%) and main treatment indications were MS (29 cases) and Graves' ophthalmopathy (13 cases). Hepatocellular damage predominated and mean time to onset was 6 weeks. Four patients died and rechallenge occurred in 19 cases.

Conclusion

MP pulses can induce severe liver injury, often with an autoimmune phenotype, particularly in patients with MS and Graves' ophthalmopathy. Consequently, these patient groups should have liver tests monitored when treated with MP to provide safer patient care.

Pharmacodynamic Study of Miransertib in Individuals with Proteus Syndrome

Proteus syndrome is a life-threatening segmental overgrowth syndrome caused by a mosaic gain-of-function AKT1 variant. There are no effective treatments for Proteus syndrome. Miransertib is an AKT1 inhibitor that, prior to this study, has been evaluated only in adult oncology trials. We designed a non-randomized, phase 0/1 pilot study of miransertib in adults and children with Proteus syndrome to identify an appropriate dosage starting point for a future efficacy trial using a pharmacodynamic endpoint. The primary endpoint was a 50% reduction in the tissue levels of AKT phosphorylation from biopsies in affected individuals. We also evaluated secondary efficacy endpoints. We found that a dose of 5 mg/m²/day (1/7 the typical dose used in oncology) led to a 50% reduction in phosphorylated AKT (pAKT) in affected tissues from five of six individuals. This dose was well tolerated. Two of the six efficacy endpoints (secondary objectives) suggested that this agent may be efficacious. We observed a decrease in a cerebriform connective tissue nevus and a reduction in pain in children. We conclude that 5 mg/m²/day of miransertib is an appropriate starting point for future efficacy trials and that this agent shows promise of therapeutic efficacy in children with Proteus syndrome.

Consensus: guidelines: best practices for detection, assessment and management of suspected acute drug-induced liver injury during clinical trials in patients with nonalcoholic steatohepatitis

BACKGROUND

The last decade has seen a rapid growth in the number of clinical trials enrolling patients with nonalcoholic fatty liver disease and nonalcoholic steatohepatitis (NASH). Due to the underlying chronic liver disease, patients with NASH often require different approaches to the assessment and management of suspected drug-induced liver injury (DILI) compared to patients with healthy livers. However, currently no regulatory guidelines or position papers systematically address best practices pertaining to DILI in NASH clinical trials.

AIMS

This publication focuses on best practices concerning the detection, monitoring, diagnosis and management of suspected acute DILI during clinical trials in patients with NASH.

METHODS

This is one of several papers developed by the IQ DILI Initiative, comprised of members from 15 pharmaceutical companies, in collaboration with DILI experts from academia and regulatory agencies. This paper is based on extensive literature review, and discussions between industry members with expertise in drug safety and DILI experts from outside industry to achieve consensus on common questions related to this topic.

RESULTS

Recommended best practices are outlined pertaining to hepatic inclusion and exclusion criteria, monitoring of liver tests, DILI detection, approach to a suspected DILI signal, causality assessment and hepatic discontinuation rules.

CONCLUSIONS

This paper provides a framework for the approach to assessment and management of suspected acute DILI during clinical trials in patients with NASH.

Cannabidiol in patients with Lennox-Gastaut syndrome: Interim analysis of an open-label extension study

Objective

Patients with Lennox‐Gastaut syndrome (LGS) who completed 1 of 2 randomized, double‐blind, placebo‐controlled trials of add‐on cannabidiol (CBD) (GWPCARE3, NCT02224560 or GWPCARE4, NCT02224690) were invited to enroll in an open‐label extension (OLE) study evaluating the long‐term safety and efficacy of CBD (GWPCARE5, NCT02224573). Herein we present an interim analysis of the safety, efficacy, and patient‐reported outcomes from this trial.

Methods

Patients received a pharmaceutical formulation of highly purified CBD oral solution (Epidiolex; 100 mg/mL), titrated from 2.5 to 20 mg/kg/d over a 2‐week titration period, in addition to their existing medications. Doses could be reduced if not tolerated or increased up to 30 mg/kg/d if thought to be of benefit.

Results

This interim analysis was based on a November 2016 data cut. Of 368 patients who completed treatment in GWPCARE3 and GWPCARE4, 366 (99.5%) enrolled in the OLE study (GWPCARE5). Median treatment duration was 38 weeks at a mean modal dose of 23 mg/kg/d. Most patients (92.1%) experienced adverse events (AEs), primarily of mild (32.5%) or moderate (43.4%) severity. The most common AEs were diarrhea (26.8%), somnolence (23.5%), and convulsion (21.3%). Thirty‐five patients (9.6%) discontinued treatment due to AEs. Liver transaminase elevations were reported in 37 patients (10.1%), of whom 29 were receiving concomitant valproic acid; 34 cases resolved spontaneously or with dose modification of CBD or concomitant medication. Median reduction from baseline in drop seizure frequency (quantified monthly over 12‐week periods) ranged from 48% to 60% through week 48. Median reduction in monthly total seizure frequency ranged from 48% to 57% across all 12‐week periods through week 48. Eighty‐eight percent of patients/caregivers reported an improvement in the patient's overall condition per the Subject/Caregiver Global Impression of Change scale.

Significance

In this study, long‐term add‐on CBD treatment had an acceptable safety profile in patients with LGS and led to sustained reductions in seizures.

Assessment of cholestasis in drug-induced liver injury by different methods

Cholestasis in drug-induced liver injury (DILI) can be assessed by biochemical and pathologic methods, but the agreement between the 2 methods remains unclear.The aim of this study was to identify the accurate method for assessment of cholestasis in DILI.The DILI standard established and revised by the Council for International Organizations of Medical Sciences (CIOMS) (R values were calculated by liver function at different time points), cholestatic liver disease guideline (European Association for the Study of the Liver, EASL), and liver pathology were used to assess, compare, and analyze the cholestasis in 133 patients with DILI.The R values at different time points in CIOMS standard had no statistical difference for the assessment of cholestatic DILI (a = 0.05, χ = 1.51, P = .679). There were statistical differences among the results of CIOMS, EASL, and pathology (a = 0.05, χ = 99.97, P < .001). EASL standard had no statistical difference with pathology (a = 0.003, χ = 8.00, P = .005).CIOMS and EASL standards based on biochemical parameters underestimated cholestatic DILI, as compared to liver pathology.

Candidate biomarkers for the diagnosis and prognosis of drug-induced liver injury: An international collaborative effort

Current blood biomarkers are suboptimal in detecting drug-induced liver injury (DILI) and predicting its outcome. We sought to characterize the natural variabilty and performance characteristics of 14 promising DILI biomarker candidates. Serum or plasma from multiple cohorts of healthy volunteers (n = 192 and n = 81), subjects who safely took potentially hepatotoxic drugs without adverse effects (n = 55 and n = 92) and DILI patients (n = 98, n = 28, and n = 143) were assayed for microRNA-122 (miR-122), glutamate dehydrogenase (GLDH), total cytokeratin 18 (K18), caspase cleaved K18, glutathione S-transferase α, alpha-fetoprotein, arginase-1, osteopontin (OPN), sorbitol dehydrogenase, fatty acid binding protein, cadherin-5, macrophage colony-stimulating factor receptor (MCSFR), paraoxonase 1 (normalized to prothrombin protein), and leukocyte cell-derived chemotaxin-2. Most candidate biomarkers were significantly altered in DILI cases compared with healthy volunteers. GLDH correlated more closely with gold standard alanine aminotransferase than miR-122, and there was a surprisingly wide inter- and intra-individual variability of miR-122 levels among healthy volunteers. Serum K18, OPN, and MCSFR levels were most strongly associated with liver-related death or transplantation within 6 months of DILI onset. Prediction of prognosis among DILI patients using the Model for End-Stage Liver Disease was improved by incorporation of K18 and MCSFR levels. Conclusion: GLDH appears to be more useful than miR-122 in identifying DILI patients, and K18, OPN, and MCSFR are promising candidates for prediction of prognosis during an acute DILI event. Serial assessment of these biomarkers in large prospective studies will help further delineate their role in DILI diagnosis and management.

Association between the concurrence of pre-existing chronic liver disease and worse prognosis in patients with an herb- Polygonum multiflorum thunb. induced liver injury: a case-control study from a specialised liver disease center in China

OBJECTIVES

The present study aimed to evaluate the association between the concurrence of pre-existing chronic liver diseases (CLD) and worse prognosis in patients with HILI.

DESIGN

A case-control study.

SETTING

Tertiary hospital specialising in liver diseases in China.

PARTICIPANTS

145 hospitalised HILI patients were assessed with respect to prognosis by comparing HILI with or without pre-existing CLD from February 2007 to January 2017. Twenty-five HILI cases with pre-existing alcoholic liver disease (ALD) or non-alcoholic fatty liver disease (NAFLD) and 200 ALD or NAFLD controls matched 1:8 for sex, age (±4 years old), body mass index (±2 kg/m2), the type of CLD, alcohol intake (±5 g/d) and the presence or absence of cirrhosis.

PRIMARY OUTCOME MEASURES

Mortality and chronicity in HILI patients with or without pre-existing CLD, and matched CLD patients.

RESULTS

Of the 193 714 hospitalised patients with liver diseases, 5703 patients met the diagnostic criteria for drug-induced liver injury (DILI), which was attributed to Polygonum multiflorum Thunb. (PMT) in 145 patients. Among these HILI patients, 22.8% (33 of 145) had pre-existing CLD, including 17 (51.5%) with ALD, 8 (24.2%) with NAFLD, 5 (15.2%) with chronic viral hepatitis and 3 (9.1%) with autoimmune liver disease. Compared with HILI patients without CLD, HILI patients with pre-existing CLD showed higher mortality (0.9% vs 9.1%, p=0.037) and higher chronicity (12.5% vs 30.3%, p=0.016). Compared with matched ALD (136 patients) or NAFLD (64 patients) patients, HILI patients with pre-existing ALD showed higher chronicity (35.3% vs 11.8%, p=0.019). Multivariate logistic regression analysis found that concurrence of pre-existing CLD was an independent risk factor for both of chronicity and mortality (OR 3.966, 95% CI 1.501 to 10.477, p=0.005), especially the chronicity (OR 3.035, 95% CI 1.115 to 8.259, p=0.030).

CONCLUSIONS

Concurrence of pre-existing CLD could be an independent risk factor for worse prognosis, especially chronicity, in PMT-related HILI.

Serum biomarkers of drug-induced liver injury: Current status and future directions

Drug-induced liver injury (DILI), which is caused by drugs and herbal or dietary supplements, remains a serious concern for drug developers, regulators, and clinicians; however, serum biomarkers utilized to detect and monitor DILI have not changed in decades and have limitations. Data-driven mathematical modeling that incorporates the release and clearance kinetics of traditional biomarkers has improved their use in the prediction of liver safety liabilities for new drug candidates. Several newer biomarkers have shown promise in terms of liver specificity, predicting the outcome of DILI events, and providing insight into its underlying mechanisms. For these new biomarkers to be qualified for regulatory acceptance, it will require their assessment in large numbers of patients who are receiving a wide range of compounds and who develop a broad spectrum of liver injuries. The ongoing and evolving international biomarker consortia should play a major role in this effort, which is likely to transform the assessment of liver safety in clinical trials and in the clinic.

The diagnosis and management of idiosyncratic drug-induced liver injury

Drug-induced liver injury (DILI) is an uncommon but important cause of liver disease that can arise after exposure to a multitude of drugs and herbal and dietary supplements. The severity of idiosyncratic DILI varies from mild serum aminotransferase elevations to the development of severe liver injury that can progress to acute liver failure resulting in death or liver transplantation within days of DILI onset. Chronic liver injury that persists for more than 6 months after DILI onset is also becoming increasingly recognized in up to 20% of DILI patients. Host demographic (age, gender, race), clinical and laboratory features at DILI onset have been associated with the severity and outcome of liver injury in DILI patients. In addition to cessation of the suspect drug, other medical interventions including the use of N-acetylcysteine and corticosteroids in selected patients have shown some clinical benefit, but additional prospective studies are needed. A number of promising diagnostic, prognostic and mechanistic serum and genetic biomarkers may help improve our understanding of the pathogenesis and treatment of idiosyncratic DILI.

Idiosyncratic Drug-Induced Acute Liver Failure: A Challenging and Distressing Scenario

BACKGROUND

Idiosyncratic Drug Induced Liver Injury (DILI) is a rare adverse event to drugs that occasionally leads to severe liver damage, being one of the leading causes of Acute Liver Failure (ALF) in developed countries. DILI is largely a diagnosis of exclusion.

DISCUSSION AND CONCLUSION

Careful history of drug taking and ruling out other competing etiologies is mandatory given that DILI can present with an extremely variable phenotype. Several prognostic scores have been developed to promptly identify patients with potential risk of developing ALF. New biomarkers to diagnose and predict DILI evolution are under study and hopefully we will benefit from these novel tools in the near future.

Optimized protocol for induction of cytochrome P450 enzymes 1A2 and 3A4 in human primary-like hepatocyte cell strain HepaFH3 to study in vitro toxicology

BACKGROUND

Drug induced liver injury (DILI) is the most frequent cause for failure of new drugs in clinical studies. Thus, toxicity studies are indispensable during drug development. The proliferative human liver cell strain HepaFH3 with promising primary-like cellular properties might be a suitable liver model for such studies, but its cytochrome-P450 (CYP) expression is still in low ranges compared to freshly isolated primary human hepatocytes.

OBJECTIVE

We aimed to optimize the induction protocol for CYP1A2 and CYP3A4 in HepaFH3 to obtain a physiologically relevant in vitro liver model.

METHODS

CYP1A2 and CYP3A4 were induced by omeprazole and rifampicin, respectively. Induction of the two CYPs was measured by qRT-PCR, immunofluorescence and by P450 Glo enzyme activity assays.

RESULTS

The optimized protocol made the experimental design six days shorter than the original procedure. CYP1A2 mRNA levels were induced 118-fold, CYP3A4 levels 36-fold. This result was also reflected at protein level. Enzymatic activity of CYP1A2 increased 3.7-fold and CYP3A4 activity increased 9.8-fold after induction.

CONCLUSIONS

We succeeded in optimizing the induction protocol for HepaFH3 to such an extent that CYP1A2 and CYP3A4 are expressed in sufficient amounts that the cell strain can be used as a physiological relevant human liver model for in vitro toxicology studies.

Herbal and Dietary Supplement-Induced Liver Injuries in the Spanish DILI Registry

BACKGROUND & AIMS

There have been increasing reports of liver injury associated with use of herbal and dietary supplements, likely due to easy access to these products and beliefs among consumers that they are safer or more effective than conventional medications. We aimed to evaluate clinical features and outcomes of patients with herbal and dietary supplement-induced liver injuries included in the Spanish DILI Registry.

METHODS

We collected and analyzed data on demographic and clinical features, along with biochemical parameters, of 32 patients with herbal and dietary supplement-associated liver injury reported to the Spanish DILI registry from 1994 through 2016. We used analysis of variance to compare these data with those from cases of liver injury induced by conventional drugs or anabolic androgenic steroid-containing products.

RESULTS

Herbal and dietary supplements were responsible for 4% (32 cases) of the 856 DILI cases in the registry; 20 cases of DILI (2%) were caused by anabolic androgenic steroids. Patients with herbal and dietary supplement-induced liver injury were a mean age of 48 years and 63% were female; they presented a mean level of alanine aminotransferase 37-fold the upper limit of normal, 28% had hypersensitivity features, and 78% had jaundice. Herbal and dietary supplement-induced liver injury progressed to acute liver failure in 6% of patients, compared with none of the cases of anabolic androgenic steroid-induced injury and 4% of cases of conventional drugs. Liver injury after repeat exposure to the same product that caused the first DILI episode occurred in 9% of patients with herbal and dietary supplement-induced liver injury vs none of the patients with anabolic androgenic steroid-induced injury and 6% of patients with liver injury from conventional drugs.

CONCLUSION

In an analysis of cases of herbal and dietary supplement-induced liver injury in Spain, we found cases to be more frequent among young women than older patients or men, and to associate with hepatocellular injury and high levels of transaminases. Herbal and dietary supplement-induced liver injury is more severe than other types of DILI and re-exposure is more likely. Increasing awareness of the hepatoxic effects of herbal and dietary supplements could help physicians make earlier diagnoses and reduce the risk of serious liver damage.

Circulating monocytes accelerate acute liver failure by IL-6 secretion in monkey

Acute liver failure (ALF) is associated with high mortality, and a poor understanding of the underlying pathophysiology has resulted in a lack of effective treatments so far. Here, using an amatoxin-induced rhesus monkey model of ALF, we panoramically revealed the cellular and molecular events that lead to the development of ALF. The challenged monkeys with toxins underwent a typical course of ALF including severe hepatic injury, systemic inflammation and eventual death. Adaptive immune was not noticeably disturbed throughout the progress of ALF. A systematic examination of serum factors and cytokines revealed that IL-6 increase was the most rapid and drastic. Interestingly, we found that IL-6 was mainly produced by circulating monocytes. Furthermore, ablation of monocyte-derived IL-6 in mice decreased liver injury and systemic inflammation following chemical injection. Our findings reveal a critical role of circulating monocytes in initiating and accelerating ALF, indicating a potential therapeutic target in clinical treatment for ALF.

Drug-induced liver injury: a safety review

INTRODUCTION

Idiosyncratic drug-induced liver injury (DILI) remains one of the most important causes of drug attrition both in the early phases of clinical drug development and in the postmarketing scenario. This is because, in spite of emerging data on genetic susceptibility variants associated to the risk of hepatotoxicity, the precise identification of the individual who will develop DILI when exposed to a given drug remains elusive.

AREAS COVERED

In this review, we have addressed recent progress made and initiatives taken in the field of DILI from a safety perspective through a comprehensive search of the literature.

EXPERT OPINION

Despite the substantial progress made over this century, new approaches using big data analysis to characterize the true incidence of DILI are needed and to categorize the drugs' hepatotoxic potential. Genetic studies have highlighted the role of the adaptive immune system yet the mechanisms leading adaptation versus progression remain to be elucidated. There is a compelling need for development and qualification of sensitive, specific, and affordable biomarkers in DILI to foster drug development, patient treatment stratification and, improvement of causality assessment methods. Gaining mechanistic insights in DILI is essential to uncover therapeutic targets and design prospective clinical trials with appropriate endpoints.

Suspected drug-induced liver injury associated with iguratimod: a case report and review of the literature

Background

Iguratimod is a novel anti-rheumatic drug with the capability of anti-cytokines as report goes. It has been reported that iguratimod is effective and safe for rheumatoid arthritis and other rheumatisms. As side effects, iguratimod can cause gastrointestinal reactions, dizziness, headache and itchy.

Case presentation

In this case report, a 60-year-old female patient was admitted with suspected drug-induced liver injury (DILI) caused by iguratimod. The causality assessment was done by the updated RUCAM, and the possibility of the case in our paper diagnosed as highly probable for the score was 9 points. Iguratimod was discontinued immediately, and methylprednisolone was used for acute liver injury and Sjogren’s syndrome. The data showed the patient has improved gradually, and she was discharged on day 27. The true incidence of iguratimod-related hepatotoxicity and its pathogenic mechanism are largely unknown. It is difficult to recognize and diagnose DILI, and there is no standard for diagnosis of DILI. At the same time, the DILI is still lack of specific treatment.

Conclusions

Based on this rare case of severe liver injury, we recommend careful monitoring of liver function throughout iguratimod treatment for diseases.

Noninvasive Imaging of Drug-Induced Liver Injury with 18F-DFA PET

Drug-induced liver failure is a significant indication for a liver transplant, and unexpected liver toxicity is a major reason that otherwise effective therapies are removed from the market. Various methods exist for monitoring liver injury but are often inadequate to predict liver failure. New diagnostic tools are needed. Methods: We evaluate in a preclinical model whether 18F-2-deoxy-2-fluoroarabinose (18F-DFA), a PET radiotracer that measures the ribose salvage pathway, can be used to monitor acetaminophen-induced liver injury and failure. Mice treated with vehicle, 100, 300, or 500 mg/kg acetaminophen for 7 or 21 h were imaged with 18F-FDG and 18F-DFA PET. Hepatic radiotracer accumulation was correlated to survival and percentage of nonnecrotic tissue in the liver. Mice treated with acetaminophen and vehicle or N-acetylcysteine were imaged with 18F-DFA PET. 18F-DFA accumulation was evaluated in human hepatocytes engrafted into the mouse liver. Results: We show that hepatic 18F-DFA accumulation is 49%-52% lower in mice treated with high-dose acetaminophen than in mice treated with low-dose acetaminophen or vehicle. Under these same conditions, hepatic 18F-FDG accumulation was unaffected. At 21 h after acetaminophen treatment, hepatic 18F-DFA accumulation can distinguish mice that will succumb to the liver injury from those that will survive it (6.2 vs. 9.7 signal to background, respectively). Hepatic 18F-DFA accumulation in this model provides a tomographic representation of hepatocyte density in the liver, with a R2 between hepatic 18F-DFA accumulation and percentage of nonnecrotic tissue of 0.70. PET imaging with 18F-DFA can be used to distinguish effective from ineffective resolution of acetaminophen-induced liver injury with N-acetylcysteine (15.6 vs. 6.2 signal to background, respectively). Human hepatocytes, in culture or engrafted into a mouse liver, have levels of ribose salvage activity similar to those of mouse hepatocytes. Conclusion: Our findings suggest that PET imaging with 18F-DFA can be used to visualize and quantify drug-induced acute liver injury and may provide information on the progression from liver injury to hepatic failure.

Novel Approaches to Causality Adjudication in Drug-Induced Liver Disease

Purpose of Review

Drug induced liver injury (DILI) is a complex diagnosis dominantly based of exclusion.

Recent Findings

Currently available causality assessment instruments are considered to be suboptimal. Expert opinion appears to be best method to adjudicate causality, but is impractical to implement on a wide scale basis. Thus, new approaches are needed, for example improving the specificity of current scoring systems. A further option would be to develop a system that utilizes computer-based scoring - which would reduce human error. Additionally, it would be ideal to have available drug specific scoring systems, based on drugs' characteristic "phenotypes" (presentation and pattern of injury). Eventually, a validated system could be integrated within the electronic health information system.

Summary

This review highlights an avenue to an improved Causality Assessment Tool.

Evaluation of liver test abnormalities in a patient-centered medical home: do liver test patterns matter?

Abnormal liver tests are extremely common in clinical practice, present with varying patterns and degrees of elevation, and can signal liver injury from a variety of causes. Responding to these abnormalities requires complex medical decision-making and merits investigation in primary care. This retrospective study investigates the association of patterns of liver test abnormality with follow-up in primary care. Using administrative data, this study includes patients with abnormal liver tests seen between 2007 and 2016 in a patient-centered medical home. Liver tests examined include serum bilirubin, aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase. Patients entered the cohort on the first liver test elevation. The outcome examined was completion of repeat testing, and the proportions of patients without follow-up were compared by patterns of index abnormality. 9545 patients met the inclusion criteria. Of these, 6155 (64.5%) possessed one liver test abnormality and 3390 (35.5%) possessed multiple abnormalities on index testing. Overall 1119 (11.7%) patients did not have repeat testing performed during the study period. A greater proportion of patients with lone abnormalities lacked repeat testing compared with those patients with multiple abnormalities. Differences in repeat testing appeared when comparing clinical patterns of abnormality, with higher proportions of follow-up in patients with testing suggestive of cholestasis. Over 11% of patients with abnormal liver tests did not undergo repeat testing during the study period. Repeat testing occurred more often in patients with multiple abnormalities and in clinical patterns suggestive of cholestasis. This study highlights a potential opportunity to improve quality of care.

Nonacetaminophen Drug-Induced Acute Liver Failure

Acute liver failure of all causes is diagnosed in between 2000 and 2500 patients annually in the United States. Drug-induced acute liver failure is the leading cause of acute liver failure, accounting for more than 50% of cases. Nonacetaminophen drug injury represents 11% of all cases in the latest registry from the US Acute Liver Failure Study Group. Although rare, acute liver failure is clinically dramatic when it occurs, and requires a multidisciplinary approach to management. In contrast with acetaminophen-induced acute liver failure, non-acetaminophen-induced acute liver failure has a more ominous prognosis with a lower liver transplant-free survival.

Update of sarilumb to treat rheumatoid arthritis based on randomized clinical trials: a systematic review

INTRODUCTION

Sarilumab is a human monoclonal antibody against Interleukin 6 α (IL-6α) receptor. Compared to tocilizumab, another IL-6 α receptor antibody, sarilumab has a different structure and higher affinity. Areas covered: In a systematic literature review, we examined all sarilumab randomized clinical trials (RCTs) in rheumatoid arthritis. The 6 reviewed RCTs included patients who were inadequate MTX, DMARD and/or TNFi responders. Sarilumab 150-200 mg every 2 weeks improved RA signs, symptoms, function and decreased radiological progression up to 52 weeks. The most common adverse events were infections and neutropenia, the latter of which will require careful observation in future trials. Examination of the effect of sero-positivity, disease duration, presence of erosions, use of previous biologic and comparisons to other biologics etc are still needed to complete understanding of this drug's profile. Long term studies, too, will be needed to assess long term tolerability Expert commentary: Results support the use of sarilumab to treat RA patients with inadequate response to MTX, other DMARDs and TNFis, although further studies are needed to fully assess its toxicity and understand the specific place of sarilumab in the RA armamentarium.

Traditional Chinese Medicine and Herb-induced Liver Injury: Comparison with Drug-induced Liver Injury

Cases of suspected herb-induced liver injury (HILI) caused by herbal Traditional Chinese Medicines (TCMs) and of drug-induced liver injury (DILI) are commonly published in the scientific literature worldwide. As opposed to the multiplicity of botanical chemicals in herbal TCM products, which are often mixtures of several herbs, conventional Western drugs contain only a single synthetic chemical. It is therefore of interest to study how HILI by TCM and DILI compare with each other, and to what extent results from each liver injury type can be transferred to the other. China is among the few countries with a large population using synthetic Western drugs as well as herbal TCM. Therefore, China is well suited to studies of liver injury comparing drugs with TCM herbs. Despite some concordance, recent analyses of liver injury cases with verified causality, using the Roussel Uclaf Causality Assessment Method, revealed major differences in HILI caused by TCMs as compared to DILI with respect to the following features: HILI cases are less frequently observed as compared to DILI, have a smaller proportion of females and less unintentional rechallenge events, and present a higher rate of hepatocellular injury features. Since many results were obtained among Chinese residents who had access to and had used Western drugs and TCM herbs, such ethnic homogeneity supports the contention that the observed differences of HILI and DILI in the assessed population are well founded.

A Multicenter, Randomized, Double-Blind, Phase 2 Study of the Efficacy and Safety of Plazomicin Compared with Levofloxacin in the Treatment of Complicated Urinary Tract Infection and Acute Pyelonephritis

Increasing antimicrobial resistance among uropathogens limits treatment options for patients with complicated urinary tract infection (cUTI). Plazomicin, a new aminoglycoside, has in vitro activity against multidrug-resistant Enterobacteriaceae, including isolates resistant to currently available aminoglycosides, as well as extended-spectrum β-lactamase-producing and carbapenem-resistant Enterobacteriaceae. We evaluated the efficacy and safety of plazomicin in a double-blind, comparator-controlled, phase 2 study in adults with cUTI or acute pyelonephritis. Patients were randomized 1:1:1 to receive intravenous plazomicin (10 or 15 mg/kg of body weight) or intravenous levofloxacin (750 mg) once daily for 5 days. Coprimary efficacy endpoints were microbiological eradication at the test of cure (TOC; 5 to 12 days after the last dose) in the modified intent-to-treat (MITT) and microbiologically evaluable (ME) populations. Overall, 145 patients were randomized to treatment. In the groups receiving plazomicin at 10 mg/kg, plazomicin at 15 mg/kg, and levofloxacin, microbiological eradication rates were, respectively, 50.0% (6 patients with microbiological eradication at TOC/12 patients treated [95% confidence interval {CI}, 21.1 to 78.9%]), 60.8% (31/51 [95% CI, 46.1 to 74.2%]), and 58.6% (17/29 [95% CI, 38.9 to 76.5%]) in the MITT population and 85.7% (6/7 [95% CI, 42.1 to 99.6%]), 88.6% (31/35 [95% CI, 73.3 to 96.8%]), and 81.0% (17/21 [95% CI, 58.1 to 94.6%]) in the ME population. In the MITT population, 66.7% (95% CI, 34.9 to 90.1%), 70.6% (95% CI, 56.2 to 82.5%), and 65.5% (95% CI, 45.7 to 82.1%) of the patients in the three groups, respectively, were assessed by the investigator to be clinically cured at TOC. Adverse events were reported in 31.8%, 35.1%, and 47.7% of the patients in the three groups, respectively. Serum creatinine values were generally stable over the course of the study. No plazomicin-treated patients with evaluable audiometry data had postbaseline sensorineural, conductive, or mixed hearing loss. In summary, plazomicin demonstrated microbiological and clinical success and an overall safety profile supportive of further clinical development. (This study has been registered at ClinicalTrials.gov under identifier NCT01096849.)

Pharmacoepigenetics in childhood acute lymphoblastic leukemia: involvement of miRNA polymorphisms in hepatotoxicity

AIM

Hepatotoxicity is one of the most common drug-related toxicities during the treatment of childhood acute lymphoblastic leukemia (ALL). Many genes involved in liver-specific signaling pathways are tightly controlled by miRNAs, and miRNA function could be modulated by SNPs. As a consequence, we hypothesized that variants in miRNAs could be associated with drug-induced hepatotoxicity.

METHODS

We analyzed 213 SNPs in 206 miRNAs in a cohort of 179 children with ALL homogeneously treated.

RESULTS

rs2648841 in miR-1208 was the most significant SNP during consolidation phase after false discovery rate correction, probably through an effect on its target genes DHFR, MTR and MTHFR.

CONCLUSION

These results point out the possible involvement of SNPs in miRNAs in toxicity to chemotherapy in children with ALL.

A Case of Levofloxacin-Induced Hepatotoxicity

Patient: Male, 36

Final Diagnosis: Levofloxacin-induced hepatotoxicity

Symptoms: Cellulitis • pain

Medication: Levofloxacin

Clinical Procedure: —

Specialty: Infectious Diseases

Acute liver failure induced by idiosyncratic reaction to drugs: Challenges in diagnosis and therapy

Acute liver failure (ALF) requires urgent attention to identify etiology and determine prognosis, in order to assess likelihood of survival or need for transplantation. Identifying idiosyncratic drug-induced liver injury (iDILI) may be particularly difficult, but the illness generally follows a subacute course, allowing time to assess outcome and find a liver graft if needed. Not all drugs that cause iDILI lead to ALF; the most common are antibiotics including anti-tuberculous medications, non-steroidal anti-inflammatory agents and herbal and dietary supplements (HDS). Determining causality remains challenging particularly if altered mentation is present; identifying the causative agent depends in part on knowing the propensity of the drugs that have been taken in the proper time interval, plus excluding other causes. In general, iDILI that reaches the threshold of ALF will more often than not require transplantation, since survival without transplant is around 25%. Treatment consists of withdrawal of the presumed offending medication, consideration of N-acetylcysteine (NAC), as well as intensive care. Corticosteroids have not proven useful except perhaps in instances of apparent autoimmune hepatitis caused by a limited number of agents. Recently developed prognostic scoring systems may also aid in predicting outcome in this setting.

Serum apolipoprotein A1 and haptoglobin, in patients with suspected drug-induced liver injury (DILI) as biomarkers of recovery

BACKGROUND

There is a clear need for better biomarkers of drug-induced-liver-injury (DILI).

AIMS

We aimed to evaluate the possible prognostic value of ActiTest and FibroTest proteins apoliprotein-A1, haptoglobin and alpha-2-macroglobulin, in patients with DILI.

METHODS

We analyzed cases and controls included in the IMI-SAFE-T-DILI European project, from which serum samples had been stored in a dedicated biobank. The analyses of ActiTest and FibroTest had been prospectively scheduled. The primary objective was to analyze the performance (AUROC) of ActiTest components as predictors of recovery outcome defined as an ALT <2x the upper limit of normal (ULN), and BILI <2x ULN.

RESULTS

After adjudication, 154 patients were considered to have DILI and 22 were considered to have acute liver injury without DILI. A multivariate regression analysis (ActiTest-DILI patent pending) combining the ActiTest components without BILI and ALT (used as references), apolipoprotein-A1, haptoglobin, alpha-2-macroglobulin and GGT, age and gender, resulted in a significant prediction of recovery with 67.0% accuracy (77/115) and an AUROC of 0.724 (P<0.001 vs. no prediction 0.500). Repeated apolipoprotein-A1 and haptoglobin remained significantly higher in the DILI cases that recovered (n = 65) versus those that did not (n = 16), at inclusion, at 4-8 weeks and at 8-12 weeks. The same results were observed after stratification on APAP cases and non-APAP cases.

CONCLUSIONS

We identified that apolipoprotein-A1 and haptoglobin had significant predictive values for the prediction of recovery at 12 weeks in DILI, enabling the construction of a new prognostic panel, the DILI-ActiTest, which needs to be independently validated.

MiR-122 and other microRNAs as potential circulating biomarkers of drug-induced liver injury

INTRODUCTION

Drug-induced liver injury (DILI) is a severe adverse drug reaction which is of major concern to patients, clinicians and the pharmaceutical industry. Accurate and rapid detection of DILI is important for patient stratification and treatment in the clinic and benefits preclinical drug design and risk assessment. MicroRNAs (miRNAs) offer a potential new and improved class of circulating biomarkers of DILI over the current gold standard biomarkers. Areas covered: This review highlights the shortcomings of the currently used panel of biomarkers and how miRNAs, primarily miR-122, show an improved level of specificity and sensitivity in the prediction of DILI. Furthermore, the use of miRNAs as potential markers of progression of DILI and specific zonated damage within the liver is discussed. Expert commentary: MiRNAs offer more sensitive and specific markers over the current biomarkers for DILI. Combinations of different miRNAs may be able to relay the location of DILI and the progression of disease. More studies using different hepatotoxins apart from acetaminophen will ultimately strengthen the case for the clinical introduction of miRNAs as biomarkers of DILI.

Usability and Patient Preference Phase 3 Study of the Sarilumab Pen in Patients with Active Moderate-to-Severe Rheumatoid Arthritis

INTRODUCTION

Sarilumab is a human monoclonal antibody that blocks the interleukin-6 receptor alpha (IL-6Rα). The phase 3 SARIL-RA-EASY study (EASY) assessed the robustness of an autoinjector (pen) for administering sarilumab when used by adults with active moderate-to-severe rheumatoid arthritis (RA) who are candidates for anti-IL-6R therapy in an unsupervised real-world setting.

METHODS

EASY was a 12-week, multicenter, randomized, open-label, parallel-group usability study of the sarilumab pen and prefilled syringe. Patients were randomized 1:1:1:1 to sarilumab 150 or 200 mg every 2 weeks (q2w) administered via pen or syringe, plus background disease-modifying antirheumatic drugs. Patients reported their ability to remove the pen cap and initiate and complete injections; negative responses were defined as product technical complaints (PTCs). The primary endpoint was the number of validated product technical failures (PTFs; PTC with a validated technical cause). This study was not powered to demonstrate bioequivalence or differences in efficacy among groups.

RESULTS

A total of 217 patients were randomized. There were 600 successful injections with the sarilumab pen in 108 patients and no pen-associated PTFs. One PTC was observed (the pen was mistakenly activated before injection). At week 12, 88% of patients indicated the pen was "easy" to use, and 98% reported they were "satisfied" with the pen. Proportions of patients achieving an American College of Rheumatology 20/50/70 response and a 28-joint disease activity score by C-reactive protein < 2.6 were similar at each dose between the pen and syringe groups, as were the pharmacokinetics. There were no clinically meaningful differences in adverse events (AEs), serious AEs, and AEs leading to discontinuation in the pen and syringe groups. The most common treatment-emergent AEs were infections and neutropenia.

CONCLUSION

This study demonstrated the ease of use and robustness of the sarilumab pen when used by patients with RA in an unsupervised setting. Pharmacokinetics, safety, and efficacy were generally similar for the pen and syringe groups (NCT02057250).

FUNDING

Sanofi Genzyme and Regeneron Pharmaceuticals, Inc.

TRIAL REGISTRATION

Clinicaltrials.gov identifier, NCT02057250.

Antiepileptic Drugs and Liver Disease

Acute, symptomatic seizures or epilepsy may complicate the course of hepatic disease. Choosing the most appropriate antiepileptic drug in this setting represents a difficult challenge, as most medications are metabolized by the liver. This article focuses on the acute and chronic treatment of seizures in patients with advanced liver disease and reviews the hepatotoxic potential of specific antiepileptic drugs. Newer antiepileptic drugs without, or with minimal, hepatic metabolism, such as levetiracetam, lacosamide, topiramate, gabapentin, and pregabalin should be used as first-line therapy. Medications undergoing extensive hepatic metabolism, such as valproic acid, phenytoin, and felbamate should be used as drugs of last resort. In special circumstances, as in patients affected by acute intermittent porphyria, exposure to most antiepileptic drugs could precipitate attacks. In this clinical scenario, bromides, levetiracetam, gabapentin, and vigabatrin constitute safe choices. For the treatment of status epilepticus, levetiracetam and lacosamide, available in intravenous preparations, are good second-line therapies after benzodiazepines fail to control seizures. Hepatotoxicity is also a rare and unexpected side effect of some antiepileptic drugs. Drugs such as valproic acid, phenytoin, and felbamate, have a well-recognized association with liver toxicity. Other antiepileptic drugs, including phenobarbital, benzodiazepines, ethosuximide, and the newer generations of antiepileptic drugs, have only rarely been linked to hepatotoxicity. Thus physicians should be mindful of the pharmacokinetic profile and the hepatotoxic potential of the different antiepileptic drugs available to treat patients affected by liver disease.

Comparative analysis of different clinical typing methods for drug-induced liver injury

AIM

To compare the clinical classification of drug-induced liver injury (DILI) by different methods and analyze their relationship with the pathological features of the liver.

METHODS

In this study, 133 patients who were clinically diagnosed with DILI and underwent liver pathological examination were enrolled. We adopted the criteria established and updated by the Council for International Organizations of Medical Sciences (CIOMS classification standard) and the guidelines developed by the European Association for the Study of the Liver in 2009 (EASL diagnostic criteria) for DILI clinical classification. The classification results were compared with liver pathological damage types to analyze the relationship between different classification standards and liver pathology.

RESULTS

The results of classification using "R value" were consistent to those using "R' value". The differences among the results of classification using the CIOMS classification standard, EASL diagnostic criteria, and liver pathology were statistically significant (P < 0.01). The percentage of cases with hepatocellular type and the overall percentage of cases with cholestatic type and mixed type diagnosed by the three methods were as follows: (CIOMS: 79.70% vs 20.30%; EASL: 54.89% vs 45.11%; liver pathology: 37.59% vs 62.41%). Based on liver pathology, the diagnostic accordance rates of "R value", "R' value", and EASL diagnostic criteria were 41.35%, 41.35%, and 51.13%, respectively. During the one-year follow-up period, 24 (18.05%) cases developed chronic DILI, including 15 (62.50%) cases with cholestasis in liver pathology.

CONCLUSION

The biochemical method based on the CIOMS classification standard and the EASL diagnostic criteria cannot objectively reflect the pathological manifestations in the liver.

Hepatic safety analysis of trabectedin: results of a pharmacokinetic study with trabectedin in patients with hepatic impairment and experience from a phase 3 clinical trial

Purpose Trabectedin is metabolized by the liver and has been associated with transient, noncumulative transaminase elevation. Two recent studies further characterize hepatic tolerability with trabectedin therapy: a phase 1 pharmacokinetic study (Study #1004; NCT01273493) in patients with advanced malignancies and hepatic impairment (HI), and a phase 3 study (Study #3007; NCT01343277) of trabectedin vs. dacarbazine in patients with advanced sarcomas and normal hepatic function. Methods In Study #1004, patients received a single 3-h intravenous (IV) infusion of trabectedin: control group, trabectedin 1.3 mg/m²; HI group (baseline total bilirubin >1.5 and ≤3× upper limit of normal [ULN]; AST and ALT ≤2.5× ULN), trabectedin 0.58 or 0.9 mg/m². In Study #3007, the trabectedin group received 1.5 mg/m² by 24-h IV infusion every 3 weeks until disease progression or unacceptable toxicity. Results In Study #1004, dose-normalized trabectedin exposure was higher in HI patients (n = 6) versus controls (n = 9) (geometric mean ratios [90% CI] AUC_last: 1.97 [1.20; 3.22]). In Study #3007, following trabectedin administration, 90% of patients had elevated ALT (32% grade 3-4) and 84% had elevated AST (17% grade 3-4). Transaminase elevations were transient and noncumulative. Progression-free survival was similar in patients with grade 3-4 hepatotoxicity (n = 109) versus grade 0-2 hepatotoxicity (n = 231) (median [95% CI]: 4.63 [4.01, 5.85] months versus 3.55 [2.73, 4.63] months; P = 0.545, HR = 0.91 [0.68-1.23]). Conclusion Trabectedin treatment of patients with HI results in higher plasma exposures. Hepatotoxicity in patients with normal liver function can be effectively addressed through dose reductions and delays.

In silico modeling to optimize interpretation of liver safety biomarkers in clinical trials

Current strategies to delineate the risk of serious drug-induced liver injury associated with drugs rely on assessment of serum biomarkers that have been utilized for many decades. In particular, serum alanine aminotransferase and total bilirubin levels are typically used to assess hepatic integrity and function, respectively. Parallel measurement of these biomarkers is utilized to identify patients with drug-induced hepatocellular jaundice ("Hy's Law" cases) which carries at least a 10% risk of death or liver transplant. However, current guidelines regarding use of these biomarkers in clinical trials can put study subjects at risk for life-threatening drug-induced liver injury, or result in over estimation of risk that may halt development of safe drugs. In addition, pharmaceutical companies are increasingly being required to conduct large and expensive clinical trials to "defend" the safety of their new drug when results from smaller trials are inconclusive. Innovative approaches and some novel biomarkers are now being employed to maximize the value of traditional biochemical tests. DILIsym®, a product of the DILIsim Initiative, utilizes serial serum alanine aminotransferase values, along with serum biomarkers of apoptosis vs necrosis, to estimate percent hepatocyte loss and total bilirubin elevations resulting from loss of global liver function. The results from analyses conducted with DILIsym have been reported to the FDA to support the safety of entolimod and cimaglermin alfa after elevations in serum alanine aminotransferase and/or bilirubin halted clinical development. DILIsym can also be utilized to determine whether rises in serum conjugated and unconjugated bilirubin are consistent with mechanisms unrelated to toxicity ( i.e. inhibition of bilirubin transport or metabolism). In silico modeling of traditional and novel drug-induced liver injury biomarker data obtained in clinical trials may be the most efficient and accurate way to define the liver safety profile of new drug candidates. Impact statement Blood tests used in clinical trials to detect and monitor drug-induced liver injury (DILI) have not changed in half a century. These tests have several shortcomings: their use has not completely prevented clinical trial participants from risk of life-threatening DILI, they can give false positive results that halt the development of safe drug candidates, and they can create liver safety "concerns" that require large additional clinical trials to accurately define DILI risk. This review highlights the use of in silico modeling to improve interpretation of the blood tests currently available to detect DILI risk in new drug candidates. This approach is increasingly being applied in clinical trials to more precisely assess the degree of hepatocellular injury and its functional impact. This new approach holds the promise of more accurately defining DILI risk in smaller clinical trials.

Acute Liver Failure

Acute liver failure (ALF) is a life-threatening condition of heterogeneous etiology. Outcomes are better with early recognition and prompt initiation of etiology-specific therapy, intensive care protocols, and liver transplantation (LT). Prognostic scoring systems include the King's College Criteria and Model for End-stage Liver Disease score. Cerebral edema and intracranial hypertension are reasons for high morbidity and mortality; hypertonic saline is suggested for patients with a high risk for developing intracranial hypertension, and when it does, mannitol is recommended as first-line therapy. Extracorporeal liver support system may serve as a bridge to LT and may increase LT-free survival in select cases.

Death and liver transplantation within 2 years of onset of drug-induced liver injury

Drug-induced liver injury (DILI) is an important cause of death and indication for liver transplantation (fatality). The role of DILI in these fatalities is poorly characterized, particularly when fatalities occur >26 weeks after DILI onset. We analyzed patients in the US Drug-Induced Liver Injury Network prospective study having a fatal outcome within 2 years of onset. Each case was reviewed by eight network investigators and categorized as DILI having a primary, a contributory, or no role in the fatality. We subcategorized primary role cases as acute, chronic, acute-on-chronic, or acute cholestatic liver failure. For contributory and no role cases, we assigned a primary cause of death. Among 1,089 patients, 107 (9.8%) fatalities occurred within 2 years. DILI had a primary role in 68 (64%), a contributory role in 15 (14%), and no role in 22 (21%); 2 had insufficient data. Among primary role cases, 74% had acute, 13% chronic, 7% acute on chronic, and 6% acute cholestatic failure. For the 15 contributory role cases, common causes of death included sepsis, malignancy, and severe cutaneous reactions with multiorgan failure. For the 22 no role cases, malignancies accounted for most fatalities. Higher bilirubin, coagulopathy, leukocytosis, and thrombocytopenia were independently associated with DILI fatalities. New R ratio Hy's law had a higher positive predictive value for overall fatality (14% versus 10%) and a stronger independent association with DILI fatalities within 26 weeks compared to the original version of Hy's law (hazard ratio, 6.2, 95% confidence interval 3.4-11.1, versus 2.2, 95% confidence interval 1.3-3.7).

CONCLUSIONS

DILI leads directly or indirectly to fatality in 7.6% of cases; 40% of these had nonacute liver failure courses. New R ratio Hy's law better identifies risk for death compared to the original Hy's law. (Hepatology 2017;66:1275-1285).