Drug rechallenge following drug-induced liver injury

Insights into medication-induced liver injury: Understanding and management strategies

Drug-induced liver injury (DILI) has increasingly become a major concern in Western countries since the late 1960s, with an estimated annual incidence of 13.9-19.1 cases per 100,000 people. DILI is a significant cause of acute liver failure, exhibiting a high mortality rate of 10-50 %. Its etiology includes medications, herbal products, and dietary supplements, exacerbated by pre-existing liver conditions, sonorities, pregnancy, and nutritional deficiencies. It is categorized into intrinsic and idiosyncratic reactions. Intrinsic DILI, dose-dependent and predictable, is primarily caused by substances like paracetamol, which leads to liver toxicity through direct metabolic pathways. In contrast, idiosyncratic DILI is less common, unpredictable, and affects susceptible individuals, with non-steroidal anti-inflammatory drugs, antibiotics, and cardiovascular agents frequently implicated in hospitals. Oxidative stress, mitochondrial dysfunction, bile salt export inhibition, and stress on the endoplasmic reticulum are some DILI-related pathophysiology. Diagnosis relies on biochemical tests, serological markers, radiological investigations, and liver biopsy. Management strategies emphasize the identification and cessation of the offending drugs, supportive care, and specific treatment options targeted to the culprit drugs. Management depends on the severity and nature of the injury.

IQ DILI Consensus Opinion: Best Practices for Rechallenge Following Suspected Drug-Induced Liver Injury in Clinical Trials

Rechallenge with study drug after suspected drug-induced liver injury (DILI) during drug development requires a comprehensive assessment of risks and benefits. Lack of universal consensus or societal guidelines makes this decision-making process more challenging and difficult to manage in clinical development. The sparse published literature is biased towards reporting cases of positive rechallenge (recurrent DILI), often with adverse outcomes. The heterogeneity of available data and inconsistent approaches to drug rechallenge likely lead to bias in our perception of the risks of rechallenge, ultimately leaving this topic controversial. The IQ DILI Causality Assessment Working Group, in collaboration with academic and regulatory experts, developed this manuscript with the following objectives: (1) understand and describe current practices via literature review and survey of practices and opinions among drug developers, academic experts, and regulators; (2) propose a consistent and structured approach to decision-making and managing the rechallenge process; (3) facilitate better understanding of the risks and benefits of rechallenge via a standardized approach to collecting rechallenge data, including outcomes and the importance of publishing rechallenge data; and (4) the role of obtaining a liver biopsy, guidance on when a biopsy might be considered, and what histologic findings can assist in making the rechallenge decision. Lastly, knowledge gaps in the drug rechallenge paradigm are highlighted alongside the proposal to standardize the collection and publication of rechallenge data to help address these gaps. This consensus expert opinion does not encourage rechallenge but provides guidance for drug developers to apply a consistent approach to rechallenge.

Selenenylsulfide Bond as a General Scaffold for Constructing Thiol Probes with Enhanced Response Rate

Leveraging disulfide (-S-S-) or diselenide (-Se-Se-) units as triggers in the design of small-molecule fluorescent probes for detecting intracellular reductive species has demonstrated high efficacy. However, selenenylsulfides, which exhibit reactivity between diselenides and disulfides, remain relatively unexplored. In this work, we compare the efficiency of -S-S-, seleno-sulfur (-Se-S-), and sulfur-selenium (-S-Se-) structural units in constructing thiol probes, disclose the scaffold of -Se-S- as a versatile recognition site for thiols, and successfully apply this unit to design a near-infrared (NIR) probe, ASC-SeS. The mechanism reveals that breaking the -Se-S- bond leads to a selenolate, which undergoes faster cyclization than the corresponding thiolate that is from the cleavage of the -S-S- or -S-Se- bond. Conjugation of this trigger unit with multiple NIR fluorophores validates the general applicability of linear selenenylsulfides in accelerating the response rate to thiols. By harnessing the superior thiol responsiveness of ASC-SeS, we employ this probe in live cells and in vivo, and elucidate a severe depletion of thiols in the drug-induced liver injury (DILI).

Liver Injury Following Intravenous Methylprednisolone Pulse Therapy in Multiple Sclerosis: The Experience from a Single Academic Liver Center

Intravenous methylprednisolone (IVMP) pulses, widely used for managing multiple sclerosis (MS) exacerbations, can lead to acute liver injury, presenting a diagnostic challenge in distinguishing between drug-induced autoimmune-like hepatitis (DI-ALH) and idiopathic autoimmune hepatitis (AIH). This study aimed to delineate the clinical and biochemical features of IVMP-induced liver injury, discern its etiology, and evaluate the efficacy of glucocorticoid (GC) therapy in treatment. A retrospective analysis of 13 relapsing MS patients with IVMP-induced liver injury was conducted. Liver injury was classified as hepatocellular, cholestatic, or mixed, with severity assessment guiding liver biopsy in selected cases. Causality was assessed using the Roussel Uclaf Causality Assessment Method (RUCAM) and the Simplified Diagnostic Criteria for AIH. All patients were initially monitored for a minimum of six months, with a mean follow-up period of 4.30 years. The median onset of liver injury was 37.46 days post-IVMP, with a mean peak alanine transaminase (ALT) level of 618.46 U/L. antinuclear antibody (ANA) positivity was observed in 61.53% of cases, with elevated serum immunoglobulin G (IgG) at 15.38%. Hepatocellular injury was universal among patients, and causality assessment predominantly supported DI-ALH. GC therapy was administered in six cases, achieving favorable outcomes in all but one, which necessitated rituximab. Biochemical normalization occurred within a mean of 55.41 days, with GC-treated patients recovering faster (48 days). These findings support the hypothesis that IVMP can induce hepatocellular injury, likely DI-ALH, during MS exacerbations. A tapering GC regimen proved effective in promoting recovery, particularly in severe cases. Additionally, this study introduced a diagnostic and therapeutic algorithm for managing IVMP-induced liver injury, offering a practical framework for clinical application.

Does the hepatologist still need to rely on aminotransferases in clinical practice? A reappraisal of the role of a classic biomarker in the diagnosis and clinical management of chronic liver diseases

Aminotransferases, particularly alanine aminotransferase (ALT), are commonly used in the detection, diagnosis, and management of chronic liver diseases. ALT, a sensitive and cost-effective marker of liver injury, remains pivotal in predicting clinical outcomes and guiding interventions in several chronic liver diseases including metabolic dysfunction-associated steatotic liver disease, and chronic viral hepatitis. This study aims to explore the evolving role of ALT as a biomarker. A comprehensive review of evidence was conducted, focusing on studies evaluating ALT thresholds, diagnostic accuracy, and integration with non-invasive liver assessment tools. Special emphasis was given to novel approaches, including artificial intelligence-driven algorithms. Expert opinions from hepatology care perspectives were considered to assess the practical implications of refining ALT-based diagnostic strategies. ALT levels are influenced by diverse factors such as age, gender, and metabolic risks, challenging the use of specific thresholds as biomarker of disease and prognosis. Emerging evidence suggests redefining ALT ranges to enhance sensitivity and accuracy in detecting liver abnormalities. The integration of ALT with advanced non-invasive diagnostic tools, artificial intelligence, and comprehensive patient assessments can optimize early detection of liver disease, thus reducing underdiagnosis, particularly in asymptomatic or vulnerable populations. This work highlights the urgency to tailor the diagnostic approaches in primary and specialised care, ensuring timely and targeted intervention to effectively address the global burden of liver diseases.

Methods for causality assessment of idiosyncratic drug-induced liver injury

The diagnosis of idiosyncratic drug-induced liver injury (DILI) is a challenging task due to the lack of specific features or definitive diagnostic tools. A minimum of clinical and pharmacological information is required, together with laboratory and imaging tests to exclude other causes of liver injury. Several standardized methods have been developed to support clinical judgement and establish causality assessment, the most widely used being the Roussel Uclaf Causality Assessment Method-RUCAM-and structured Expert Opinion. More recently, an evidence-based, revised RUCAM, Electronic Causality Assessment Method-RECAM-has been developed and, although still a work in progress, may replace RUCAM scoring in the future. International collaborative networks and ongoing research efforts are key to advancing biomarker qualification and validation and developing new in vitro patient-based methods that will help improve DILI diagnosis and move towards a personalized medicine approach.

Tolvaptan safety in autosomal-dominant polycystic kidney disease; a focus on idiosyncratic drug-induced liver injury liabilities

Tolvaptan is a vasopressin V2 receptor antagonist which has proven to be an effective and mostly well-tolerated agent for the treatment of autosomal-dominant polycystic kidney disease. However, its administration is associated with rare but serious idiosyncratic liver injury, which has warranted a black box warning on the drug labels and frequent monitoring of liver blood tests in the clinic. This review outlines mechanistic investigations that have been conducted to date and constructs a working narrative as an explanation for the idiosyncratic drug-induced liver injury (IDILI) events that have occurred thus far. Potential risk factors which may contribute to individual susceptibility to DILI reactions are addressed, and key areas for future investigative/clinical development are highlighted.

High mobility group box1 as a danger signal inducing the infiltration of neutrophils and macrophages in thioacetamide-induced rat liver injury

The liver, a major organ involved in substance metabolism, is highly susceptible to toxicity induced by chemicals and their metabolites. Although damage-associated molecular patterns (DAMPs) have been implicated in the development of sterile inflammation following cell injury, their involvement in chemically induced hepatocellular injury remains underexplored. This study aimed to determine the role of high-mobility group box 1 (HMGB1), a DAMP, in a rat model of liver injury treated with thioacetamide, a hepatotoxicant. The rats were administered thioacetamide and treated with HMGB1 neutralizing antibody. Histopathological analysis revealed the absence of significant differences between control rats and HMGB1 neutralizing antibody-treated rats. However, HMGB1 neutralizing antibody-treated rats showed a reduction in the hepatic devitalization enzymes, a decrease in the number of anti-inflammatory cluster of differentiation CD163+ M2 macrophages and neutrophils in the injured area, and a decrease in cytokine expression. These results suggest that HMGB1 leads to the progression of inflammation after chemically induced hepatocyte injury and may represent a therapeutic target for mitigating such injury.

Review article: Recommendations for detection, assessment and management of suspected drug-induced liver injury during clinical trials in oncology patients

BACKGROUND

Drug-induced liver injury (DILI) is a major concern for oncology drugs in clinical practice and under development. Monitoring cancer patients for hepatotoxicity is challenging as these patients may have abnormal liver tests pre-treatment or on-study for many reasons including liver injury due to past oncology treatments, hepatic metastases, medical co-morbidities such as heart failure, and concomitant medications. At present, there are no regulatory guidelines or position papers that systematically address best practices pertaining to DILI detection, assessment and management in oncology patients.

AIMS

The goals of this review are (1) to examine and interpret the available evidence and (2) to make recommendations for detection, monitoring, adjudication, and management of suspected hepatocellular DILI during oncology clinical trials.

METHODS

This manuscript was developed by the IQ Consortium (International Consortium for Innovation and Quality in pharmaceutical development) DILI Initiative that consists of members from 17 pharmaceutical companies, in collaboration with academic and regulatory DILI experts. The manuscript is based on extensive literature review, expert interpretation of the literature, and several rounds of consensus discussions.

RESULTS

This review highlights recommendations for patient eligibility for clinical trials with or without primary/metastatic liver involvement, as well as changes in liver tests that should trigger increased monitoring and/or discontinuation of study drug. Guidance regarding causality assessment for suspected DILI events, rechallenge and dose-modification is provided.

CONCLUSIONS

This review brings together evidence-based recommendations and expert opinion to provide the first dedicated consensus for best practices in detection, assessment, and management of DILI in oncology clinical trials.

[Adverse effects of the tezacaftor/ivacaftor/elexacaftor combination that may lead to discontinuation: About a series of 10 cases]

INTRODUCTION

Cystic fibrosis transmembrane regulator (CFTR) channel modulators (ivacaftor, lumacaftor, tezacaftor and elexacaftor) represent a major advance in the management of cystic fibrosis. However, few data are available on the real-life safety profile of these medications, in particular on adverse events that may lead to their discontinuation. The aim of this study is to describe the characteristics and evolution of adverse reactions to the tezacaftor/ivacaftor/elexacaftor combination that led to discontinuation and were reported to the Centre régional de pharmacovigilance (CRPV) in Rennes (France).

MATERIALS AND METHODS

A retrospective study was conducted from December 2021 to May 2023, focusing on cases of discontinuation of the tezacaftor/ivacaftor/elexacaftor combination due to the occurrence of one or more adverse effects, and reported to the CRPV of Rennes, France.

RESULTS

Ten cases of drug discontinuation were reported to the Rennes CRPV (6 women/4 men). Adverse effects mainly involved neuropsychiatric disorders (n=6), followed by liver disorders (n=2), ear, nose and throat disorders (n=1), and digestive disorders (n=1). The average duration of treatment at discontinuation was 339.8 [39-668] days. The drug was reintroduced in 7 patients on average 48.7 [7-123] days after discontinuation, with a dosage adjustments (n=4) consisting of changes in dosing times or a reduction in daily doses, with varying success in alleviating adverse symptoms depending on the case.

CONCLUSION

This small case series suggests that neuropsychiatric adverse effects may occur more frequently than initially described after initiation of tezacaftor/ivacaftor/elexacaftor, and should be carefully screened and monitored. Dosage or administration schedule modifications may be considered for patients experiencing these adverse effects. Further pharmacovigilance studies are needed to better understand the adverse effect profiles of "caftors", their possible risk factors, and the impact of adjusting dosing modalities.

Rechallenge in idiosyncratic drug-induced liver injury: An analysis of cases in two large prospective registries according to existing definitions

INTRODUCTION

Data on positive rechallenge in idiosyncratic drug-induced liver injury (DILI) are scarce. We aim to analyse the clinical presentation, outcome and drugs associated with positive rechallenge in two DILI registries.

METHODS

Cases from the Spanish and Latin American DILI registries were included. Demographics, clinical characteristics and outcome of cases with positive rechallenge according to CIOMS/RUCAM and current definitions were analysed.

RESULTS

Of 1418 patients with idiosyncratic DILI, 58 cases had positive rechallenge (4.1%). Patients with positive rechallenge had shorter duration of therapy (p=0.001) and latency (p=0.003). In patients with rechallenge, aspartate transaminase levels were increased (p=0.026) and showed a prolonged time to recovery (p=0.020), albeit no differences were seen in terms of fatal outcomes. The main drug implicated in rechallenge was amoxicillin-clavulanate (17%). The majority of re-exposure events were unintentional (71%). Using both existing definitions of positive rechallenge, there were four cases which exclusively fulfilled the current criteria and five which only meet the historical definition. All cases of positive rechallenge, irrespective of the pattern of damage, fulfilled the criteria of either alanine transaminase (ALT) ≥3 times the upper limit of normal (ULN) and/or alkaline phosphatase (ALP) ≥2 times ULN.

CONCLUSIONS

Episodes of rechallenge were characterised by shorter duration of therapy and latency, and longer time to resolution, but did not show an increased incidence of fatal outcome. Based on our findings, ALT ≥3 times ULN and/or ALP ≥2 times ULN, regardless of the pattern of damage, is proposed as a new definition of rechallenge in DILI.

Chinese guideline for the diagnosis and treatment of drug-induced liver injury: an update

Drug-induced liver injury (DILI) is an important adverse drug reaction that can lead to acute liver failure or even death in severe cases. Currently, the diagnosis of DILI still follows the strategy of exclusion. Therefore, a detailed history taking and a thorough and careful exclusion of other potential causes of liver injury is the key to correct diagnosis. This guideline was developed based on evidence-based medicine provided by the latest research advances and aims to provide professional guidance to clinicians on how to identify suspected DILI timely and standardize the diagnosis and management in clinical practice. Based on the clinical settings in China, the guideline also specifically focused on DILI in chronic liver disease, drug-induced viral hepatitis reactivation, common causing agents of DILI (herbal and dietary supplements, anti-tuberculosis drugs, and antineoplastic drugs), and signal of DILI in clinical trials and its assessment.

Industry Review of Best Practices for Risk Management of Drug-Induced Liver Injury from Development to Real-World Use

The relative treatment benefit of a drug for patients during development, marketing authorization review, or after approval includes an assessment of the risk of drug-induced liver injury (DILI). In this article, the Pharmacovigilance and Risk Mitigation Working Group of the IQ-DILI Initiative launched in June 2016 within the International Consortium for Innovation and Quality in Pharmaceutical Development presents and reviews three key topics for essential risk management activities to identify, characterize, monitor, mitigate, and communicate DILI risk associated with small molecules during drug development. The three topics are: (1) Current best practices for characterizing the DILI phenotype and the severity and incidence of DILI in the treatment population, including DILI identification, prediction and recovery. (2) Characterization of the relative treatment benefit for patients who will be exposed to a drug and the attendant risk of DILI in conjunction with existing global risk mitigation strategies. (3) Implementation of risk mitigation strategies during drug development highlighting patient factors, healthcare settings and site of product administration, and prescriber and healthcare provider factors. Industry guidance is provided for assessing whether the product labeling is sufficient to minimize the risk of DILI or whether a United States Food and Drug Administration (FDA) Risk Evaluation and Mitigation Strategy (REMS) or European Medicines Agency (EMA) Risk Management Plan (RMP) with additional Risk Minimization Measures (aRMM) is needed.

Enhanced efficacy with reduced toxicity of tripterygium glycoside tablet by compatibility with total glucosides of paeony for rheumatoid arthritis therapy

BACKGROUND AND AIMS

Drug-induced liver injury remains a critical issue to hinder clinical application of Tripterygium Glycosides Tablets (TGTs) for rheumatoid arthritis (RA) therapy. Combination of TGTs with Total Glucosides of Peony (TGP) may be the most common therapeutic strategy for enhancing TGTs' efficacy and reducing its toxicity. Herein, we aimed to investigate the efficacy-enhancing and toxicity-reducing properties and mechanisms of TGT-TGP combination.

METHODS

Both TGT-induced acute and chronic liver injury animal models were established. ELISA, transmission electron microscopy, immunohistochemistry, western blot and quantitative PCR were performed to determine the efficacy, toxicity and regulatory mechanisms of TGT-TGP combination.

RESULTS

The compatibility of TGP significantly reduced the abnormal serum ALT and AST levels, and improved liver histopathological changes in both acute and chronic DILI animal models induced by TGTs, with the most effective dosage of TGP-M (medium-dose TGP, 450 mg/kg). Additionally, TGP and TGT synergistically alleviated joint swelling and improved the elevation of serum inflammatory factors, in line with the positive changes in joint histopathological features of collagen induced arthritis mice, with the same effective dosage of TGP-M following 5 weeks' drug combination treatment. Mechanically, TGT significantly increased the number of autophagosomes and the expression of LC3II protein while reducing p62 protein expression in the liver tissues, which were significantly reversed by the compatibility with TGP, similar to the findings based on the inflamed joint tissues.

CONCLUSIONS

These findings suggest an enhanced efficacy with reduced toxicity of TGT by the compatibility with TGP for RA therapy, possibly through regulating various autophagy-related proteins.

Nomenclature, diagnosis and management of drug-induced autoimmune-like hepatitis (DI-ALH): An expert opinion meeting report

Drug-induced liver injury (DILI) can mimic almost all other liver disorders. A phenotype increasingly ascribed to drugs is autoimmune-like hepatitis (ALH). This article summarises the major topics discussed at a joint International Conference held between the Drug-Induced Liver Injury consortium and the International Autoimmune Hepatitis Group. DI-ALH is a liver injury with laboratory and/or histological features that may be indistinguishable from those of autoimmune hepatitis (AIH). Previous studies have revealed that patients with DI-ALH and those with idiopathic AIH have very similar clinical, biochemical, immunological and histological features. Differentiating DI-ALH from AIH is important as patients with DI-ALH rarely require long-term immunosuppression and the condition often resolves spontaneously after withdrawal of the implicated drug, whereas patients with AIH mostly require long-term immunosuppression. Therefore, revision of the diagnosis on long-term follow-up may be necessary in some cases. More than 40 different drugs including nitrofurantoin, methyldopa, hydralazine, minocycline, infliximab, herbal and dietary supplements (such as Khat and Tinospora cordifolia) have been implicated in DI-ALH. Understanding of DI-ALH is limited by the lack of specific markers of the disease that could allow for a precise diagnosis, while there is similarly no single feature which is diagnostic of AIH. We propose a management algorithm for patients with liver injury and an autoimmune phenotype. There is an urgent need to prospectively evaluate patients with DI-ALH systematically to enable definitive characterisation of this condition.

The heparan sulfate mimetic Muparfostat aggravates steatohepatitis in obese mice due to its binding affinity to lipoprotein lipase

BACKGROUND AND PURPOSE

Heparanase is the only confirmed endoglycosidase that cleaves heparan sulfate (HS), a ubiquitous glycosaminoglycan with various essential roles in multiple pathological processes. Thus, the development of heparanase inhibitors has become an attractive strategy for drug discovery, especially in tumour therapy, in which HS mimetics are the most promising compounds. The various biological effects of heparanase also suggest a role for HS mimetics in many non-cancer indications, such as type 1 diabetes. However, the potential benefits of HS mimetics in obesity-related type 2 diabetes have not been elucidated.

EXPERIMENTAL APPROACH

In this study, we investigated muparfostat (PI-88), a developed HS mimetic currently enrolled in Phase III clinical trials, in obese mouse models and in vitro cultured murine hepatocytes.

KEY RESULTS

Daily administration of muparfostat for 4 weeks caused hyperlipidaemia and aggravated hepatic steatosis in obese mice models, but not in lean animals. In cultured hepatocytes, muparfostat did not alter lipid accumulation. Acute tests suggested that muparfostat binds to lipoprotein lipase in competition with HS on vascular endothelial cell surfaces, thereby reducing the degradation of circulating triglycerides by lipoprotein lipase and subsequent uptake of fatty acids into vascular endothelial cells and causing hyperlipidaemia. This hyperlipidaemia aggravates hepatic steatosis and causes liver injury in muparfostat-treated obese mice.

CONCLUSIONS AND IMPLICATIONS

The binding activity of HS mimetics to lipoprotein lipase should be investigated as an additional pharmacological effect during heparanase inhibitor drug discovery. This study also provides novel evidence for an increased risk of drug-induced liver injury in obese individuals.

A series of homeopathic remedies-related severe drug-induced liver injury from South India

INTRODUCTION

Homeopathic remedies are highly diluted formulations without proven clinical benefits, traditionally believed not to cause adverse events. Nonetheless, published literature reveals severe local and non-liver-related systemic side effects. We present the first series on homeopathy-related severe drug-induced liver injury (DILI) from a single center.

METHODS

A retrospective review of records from January 2019 to February 2022 identified 9 patients with liver injury attributed to homeopathic formulations. Competing causes were comprehensively excluded. Chemical analysis was performed on retrieved formulations using triple quadrupole gas chromatography-mass spectrometry and inductively coupled plasma atomic emission spectroscopy.

RESULTS

Males predominated with a median age of 54 years. The most typical clinical presentation was acute hepatitis, followed by acute on chronic liver failure. All patients developed jaundice, and ascites were notable in one-third of the patients. Five patients had underlying chronic liver disease. COVID-19 prevention was the most common indication for homeopathic use. Probable DILI was seen in 77.8%, and hepatocellular injury predominated (66.7%). Four (44.4%) patients died (3 with chronic liver disease) at a median follow-up of 194 days. Liver histopathology showed necrosis, portal and lobular neutrophilic inflammation, and eosinophilic infiltration with cholestasis. A total of 29 remedies were consumed between 9 patients, and 15 formulations were analyzed. Toxicology revealed industrial solvents, corticosteroids, antibiotics, sedatives, synthetic opioids, heavy metals, and toxic phyto-compounds, even in 'supposed' ultra-dilute formulations.

CONCLUSION

Homeopathic remedies potentially result in severe liver injury, leading to death in those with underlying liver disease. The use of mother tinctures, insufficient dilution, poor manufacturing practices, adulteration and contamination, and the presence of direct hepatotoxic herbals were the reasons for toxicity. Physicians, the public, and patients must realize that Homeopathic drugs are not 'gentle placebos.'

Clinical Pattern of Tolvaptan-Associated Liver Injury in Trial Participants With Autosomal Dominant Polycystic Kidney Disease (ADPKD): An Analysis of Pivotal Clinical Trials

RATIONALE & OBJECTIVE

Tolvaptan is associated with risk of drug-induced liver injury when used to treat autosomal dominant polycystic kidney disease (ADPKD). After this risk was described based on the clinical trials TEMPO 3:4 and TEMPO 4:4, additional data from the REPRISE trial and a long-term extension of TEMPO 4:4, REPRISE, and other tolvaptan trials in ADPKD have become available. To further characterize the hepatic safety profile of tolvaptan, an analysis of the expanded dataset was conducted.

STUDY DESIGN

Analysis of safety data from prospective clinical trials of tolvaptan.

SETTING & PARTICIPANTS

Multicenter clinical trials including more than 2,900 tolvaptan-treated participants, more than 2,300 with at least 18 months of drug exposure.

INTERVENTION

Tolvaptan administered twice daily in split-dose regimens.

OUTCOMES

Frequency of liver enzyme level increases detected by regular laboratory monitoring.

RESULTS

In the placebo-controlled REPRISE trial, more tolvaptan- than placebo-treated participants (38 of 681 [5.6%] vs 8 of 685 [1.2%]) experienced alanine aminotransferase level increases to >3× the upper limit of normal (ULN), similar to TEMPO 3:4 (40 of 957 [4.4%] vs 5 of 484 [1.0%]). No participant in REPRISE or the long-term extension experienced concurrent alanine aminotransferase level increases to >3× ULN and total bilirubin increases to >2× ULN ("Hy's Law" laboratory criteria). Based on the expanded dataset, liver enzyme increases most often occurred within 18 months after tolvaptan initiation and were less frequent thereafter. Increased levels returned to normal or near normal after treatment interruption or discontinuation. Thirty-eight patients were rechallenged with tolvaptan after the initial drug-induced liver injury episode, with return of liver enzyme level increases in 30; 1 additional participant showed a clinical "adaptation" after the initial episode, with resolution of the enzyme level increases despite continuation of tolvaptan.

LIMITATIONS

Retrospective analysis.

CONCLUSIONS

The absence of Hy's Law cases in REPRISE and the long-term extension trial support monthly liver enzyme monitoring during the first 18 months of tolvaptan exposure and every 3 months thereafter to detect and manage enzyme level increases, as is recommended on the drug label.

FUNDING

Otsuka Pharmaceutical Development & Commercialization, Inc.

TRIAL REGISTRATION

Trials included in the dataset were registered at ClinicalTrials.gov with study numbers NCT00428948 (TEMPO 3:4), NCT01214421 (TEMPO 4:4), NCT02160145 (REPRISE), and NCT02251275 (long-term extension).

Gomphrena globosa L. extract alleviates carbon tetrachoride-induced liver injury in mice by activating antioxidant signaling pathways and promoting autophagy

BACKGROUND

Carbon tetrachloride (CCl₄) is highly toxic to animal liver and is a major contributor to liver injury. Gomphrena globosa L. (GgL) is an edible plant with anti-inflammation and antioxidation properties. The aim of this study was to investigate the potential therapeutic effects of GgL on liver injury.

METHODS AND RESULTS

A model of chronic liver injury in mice was established by intraperitoneal injection of CCl₄ (0.4 mL/kg) for 3 weeks, and the mice were treated intraperitoneally with different concentrations of GgL crude extract (GgCE; 100, 200, 300 mg/kg) or Bifendatatum (Bif; 20 mg/kg) in the last 2 weeks. The results showed that GgCE treatment alleviated the liver injury, improved the pathological changes caused by CCl₄ on the mice liver, and enhance the antioxidant capacity. We also found that GgCE increased the expression of antioxidant stress related proteins, decreased the phosphorylation levels of autophagy related proteins PI3K and mTOR, and decreased the expression of LC3 II and P62 proteins.

CONCLUSION

These results suggest that GgCE alleviated CCl₄-induced chronic liver injury in mice by activating antioxidant signaling pathways and promoting autophagy, indicating a potential therapeutic effect of GgCE on liver injury.

Standard Venipuncture vs a Capillary Blood Collection Device for the Prospective Determination of Abnormal Liver Chemistry

Background

Abnormal liver function is a common manifestation of human disease and may also occur in approved and investigational medications as drug-induced liver injury (DILI). Capillary blood collection devices may allow for more frequent and convenient measurement outside of the clinic. Validation of such approaches is lacking.

Methods

This prospective, biospecimens collection study evaluated the Tasso+ in patients with abnormal liver tests (NCT05259618). The primary objective was to define the concordance of alanine aminotransferase (ALT) obtained via Tasso+ compared to standard venipuncture. Secondary objectives included measurement of 14 other analytes and patient surveys. At the time of venipuncture, 2 Tasso+ samples were collected: one was centrifuged and shipped, and the other was refrigerated and shipped as whole blood.

Results

Thirty-six patients with elevated ALT values were enrolled. In total, 100 venipuncture, 50 Tasso+ centrifuged, and 48 Tasso+ whole blood samples were obtained. Tasso+ centrifuged samples demonstrated concordance correlation coefficients (CCC) of >0.99 for ALT, alkaline phosphatase (ALP), aspartate aminotransferase (AST), and total bilirubin and CCC >0.95 for albumin, chloride, enzymatic creatinine, serum glucose, magnesium, and phosphorus. Tasso+ whole blood showed CCC of >0.99 for AST, bilirubin total, and enzymatic creatinine and CCC >0.95 for ALT, ALP, albumin, magnesium, and phosphorus. Hemolysis was comparable across the 3 sample types, but its impact was reflected in the Tasso+ potassium data. Patient feedback indicated a very favorable patient experience.

Conclusions

The capillary blood collection device, Tasso+, showed substantial to almost perfect concordance to standard venipuncture for measurement of abnormal liver function. Studies are ongoing to validate longitudinal sampling outside of the clinic.

Clinicaltrials.gov Registration Number: NCT05259618

The progression of chronicity and autoimmune hepatitis in recurrent drug-induced liver injury

BACKGROUND AND AIMS

Recurrent drug-induced liver injury (DILI) is not well documented. We retrospectively analysed the characteristics of patients who had a history of two separate DILI episodes due to different drugs.

METHODS

We collected data from 57 patients with recurrent DILI from 9582 confirmed DILI cases. Demographic, laboratory, and clinical data from both episodes were collected and analysed to determine the relationship between recurrent DILI, chronic DILI, and autoimmune hepatitis (AIH).

RESULTS

The incidence rate of recurrent DILI in our cohort was 0.59%. Most of the 57 patients with recurrent DILI were female (73.68%). The latency period of the initial episode was 30 days, whereas that of the second episode was 13 days (P = 0.003). The pattern of liver injury was not significantly different between episodes (P = 0.52). Laboratory indicators, such as alanine aminotransferase, aspartate transaminase, alkaline phosphatase, and total bilirubin, were significantly lower in the second episode than in the initial episode (P < 0.05). The incidence of chronic DILI was 43.86% during the initial episode and increased to 63.16% during the second episode. After the initial episode, 15 patients developed AIH during the second episode.

CONCLUSIONS

The latency period of recurrent DILI was gradually shortened. The clinical indices of liver injury tended to be less elevated during the second episode. Female post-menopausal patients with abnormal serum immunoglobulin G levels may be predisposed to AIH. The second DILI episode was more likely to have features of AIH.

Impact of Prior Drug Allergies on the Risk, Clinical Features, and Outcomes of Idiosyncratic Drug-Induced Liver Injury in Adults

BACKGROUND

Prior drug allergies are common and may increase susceptibility to adverse medication effects. The aim of this study was to compare the frequency, clinical features, and outcomes of DILI among patients with and without a history of prior drug allergy.

METHODS

The EMR at a large liver referral center was searched for all DILI encounters using ICD-10 T-codes for drug poisoning/toxicity and K-71 codes for toxic liver injury between 10/1/2015 and 9/30/2019. Clinically significant liver injury was identified using predefined laboratory criteria, and cases were adjudicated using a 5-point expert opinion scale: 1/2/3 = probable DILI and 4/5 = non-DILI. Drug allergy was defined as a history of anaphylaxis, hives, rash, or pruritus after drug exposure.

RESULTS

Among 766,930 patient encounters, 127 unique patients met inclusion criteria with 72 (56.7%) cases adjudicated as probable DILI and 55 (43.3%) as non-DILI. In the probable DILI group, the most frequent suspect drug classes were: antimicrobials (41.9%), herbal and dietary supplements (9.5%), and antineoplastics (8.1%). Twenty-three of the 72 DILI patients (31.9%) had a history of drug allergy before the DILI episode compared to 16 (29.1%) of the 55 non-DILI cases (p = 0.89). However, none of the allergy drugs and suspect DILI drugs were the same although many were in the same drug class. DILI patients with a prior drug allergy were more likely to be female (73.9% vs. 44.9%, p = 0.04) and have lower serum bilirubin (4.0 vs. 7.8, p = 0.08) and INR (1.1 vs. 1.6, p = 0.043) levels at presentation. The likelihood of death or liver transplantation among probable DILI cases with prior drug allergy was lower than those without prior drug allergy (0% vs. 8.2%, p = 0.35). The suspect drug was subsequently documented in the "Drug Allergy" section of the EMR in only 23 (31.9%) of the 72 probable DILI patients, and these patients were more likely to present with a rash (7% vs. 2%, p = 0.006) and higher serum bilirubin levels (10.5 vs. 4.7, p = 0.008) compared to those in whom the suspect drug was not listed as "drug allergy."

CONCLUSION

A prior drug allergy history was not associated with a greater likelihood of developing DILI compared to other causes of acute liver injury. However, the probable DILI patients with a history of prior drug allergy tended to have less severe liver injury and clinical outcomes. The low rate of suspect drug documentation in the "Drug Allergy" section of EMR after a DILI episode is of concern and could lead to avoidable harm from inadvertent suspect drug re-challenge.

Impact of pharmacist active consultation on clinical outcomes and quality of medical care in drug-induced liver injury inpatients in general hospital wards: A retrospective cohort study

The utility of pharmacist consultation for drug-induced liver injury (DILI) management has not been explored. This retrospective cohort study evaluated the impact of a pharmacist active consultation (PAC) service on the management and outcome in patients with DILI. Consecutive patients meeting clinical biochemical criteria for DILI were enrolled at a tertiary teaching hospital between 1 January 2020 and 30 April 2022. The Roussel Uclaf Causality Assessment Method was used to assess causality between drug use and liver injury for each suspected DILI patient. Included patients were grouped according to whether they received PAC, and a proportional hazard model with multivariate risk adjustment, inverse probability of treatment weighting (IPTW), and propensity score matching (PSM) was used to assess DILI recovery. In the PSM cohort, the quality of medical care was compared between PAC and no PAC groups. A total of 224 patients with DILI (108 who received PAC and 116 who did not) were included in the analysis. Of these patients, 11 (10%) were classified as highly probable, 58 (54%) as probable, and 39 (36%) as possible DILI in the PAC group, while six patients (5%) were classified as highly probable, 53 (46%) as probable, and 57 (49%) as possible DILI in the no PAC group (p = 0.089). During patient recovery, PAC was associated with a ∼10% increase in the cumulative 180-day recovery rate. The PAC group had a crude hazard ratio (HR) of 1.73 [95% confidence interval (CI): 1.23–2.43, p = 0.001] for DILI 180-day recovery, which remained stable after multivariate risk adjustment (HR = 1.74, 95% CI: 1.21–2.49, p = 0.003), IPTW (HR = 1.72, 95% CI: 1.19–2.47, p = 0.003), and PSM (HR = 1.49, 95% CI: 1.01–2.23, p = 0.046). In the PSM cohort, PAC was more likely to identify suspect drugs (90% vs. 60%, p < 0.001) and lead to timely withdrawal of the medication (89% vs. 57%, p < 0.001). Thus, PAC is associated with a better quality of medical care for patients with DILI and can improve patient outcomes.

Clinical Significance of Transient Asymptomatic Elevations in Aminotransferase (TAEAT) in Oncology

Monitoring for liver injury remains an important aspect of drug safety assessment, including for oncotherapeutics. When present, drug-induced liver injury may limit the use or result in the discontinuation of these agents. Drug-induced liver injury can exhibit with a wide spectrum of clinical and biochemical manifestations, ranging from transient asymptomatic elevations in aminotransferases (TAEAT) to acute liver failure. Numerous oncotherapeutics have been associated with TAEAT, with published reports indicating a phenomenon in which patients may be asymptomatic without overt liver injury despite the presence of grade ≥3 aminotransferase elevations. In this review, we discuss the occurrence of TAEAT in the context of oncology clinical trials and clinical practice, as well as the clinical relevance of this phenomenon as an adverse event in response to oncotherapeutics and the related cellular and molecular mechanisms that may underlie its occurrence. We also identify several gaps in knowledge relevant to the diagnosis and the management of TAEAT in patients receiving oncotherapeutics, and identify areas warranting further study to enable the future development of consensus guidelines to support clinical decision-making.

Tinospora Cordifolia (Giloy)-Induced Liver Injury During the COVID-19 Pandemic-Multicenter Nationwide Study From India

Tinospora cordifolia (Giloy) is an herbal supplement commonly used in the Indian alternative medicine system Ayurveda. This herb has been promoted to the public in India as an immune booster to prevent novel coronavirus disease 2019. However, small reports have recently shown an association between Giloy use and the development of herb-induced liver injury (HILI) with autoimmune features in some patients. This large retrospective Indian multicenter study spanning 13 centers at nine locations was designed to identify features and outcomes of HILI temporally associated with Giloy use. Chemical and toxicological analyses of retrieved Giloy samples using state-of-the-art methods were also performed. We report 43 patients, of whom more than half were female, with a median time from initial Giloy consumption to symptom onset of 46 days. Patients presented with acute hepatitis, acute worsening of chronic liver disease (CLD, the most common clinical presentation), or acute liver failure. Causality assessment revealed probable liver injury in 67.4%. The most common autoantibody detected was anti-nuclear antibody. Liver biopsy in a subset revealed HILI associated with autoimmune features and hepatocyte and canalicular cholestasis and neutrophilic and eosinophilic infiltration. Conclusion: Giloy is associated with acute hepatitis with autoimmune features and can unmask autoimmune hepatitis (AIH) in people with silent AIH-related CLD. Further studies on the safety (and efficacy) of untested but heavily promoted herbals in alternative systems of medicine are an unmet need in the interests of public health and are especially important during this global health emergency.

Membrane-delimited signaling and cytosolic action of MG53 preserve hepatocyte integrity during drug-induced liver injury

BACKGROUND & AIMS

Drug-induced liver injury (DILI) remains challenging to treat and is still a leading cause of acute liver failure. MG53 is a muscle-derived tissue-repair protein that circulates in the bloodstream and whose physiological role in protection against DILI has not been examined.

METHODS

Recombinant MG53 protein (rhMG53) was administered exogenously, using mice with deletion of Mg53 or Ripk3. Live-cell imaging, histological, biochemical, and molecular studies were used to investigate the mechanisms that underlie the extracellular and intracellular action of rhMG53 in hepatoprotection.

RESULTS

Systemic administration of rhMG53 protein, in mice, can prophylactically and therapeutically treat DILI induced through exposure to acetaminophen, tetracycline, concanavalin A, carbon tetrachloride, or thioacetamide. Circulating MG53 protects hepatocytes from injury through direct interaction with MLKL at the plasma membrane. Extracellular MG53 can enter hepatocytes and act as an E3-ligase to mitigate RIPK3-mediated MLKL phosphorylation and membrane translocation.

CONCLUSIONS

Our data show that the membrane-delimited signaling and cytosolic dual action of MG53 effectively preserves hepatocyte integrity during DILI. rhMG53 may be a potential treatment option for patients with DILI.

LAY SUMMARY

Interventions to treat drug-induced liver injury and halt its progression into liver failure are of great value to society. The present study reveals that muscle-liver cross talk, with MG53 as a messenger, serves an important role in liver cell protection. Thus, MG53 is a potential treatment option for patients with drug-induced liver injury.

miR-26a-5p protects against drug-induced liver injury via targeting bid

BACKGROUNDS

miR-26a-5p is a short noncoding RNA that is abnormally expressed in drug-induced liver injury (DILI), but its pathophysiologic role in the mechanism of disease in DILI is still vague.

METHODS

The expression of miR-26a-5p, viability of hepatic stellate cells (HSCs) proliferation, and apoptosis were explored via real-time PCR, CCK-8 assay, Tunel fluorescence, and flow cytometry. The expression of Bid was detected via Western blot assays, real-time PCR, and immunofluorescence. The apoptosis-associated proteins were determined through Western blot. The interaction between miR-26a-5p and Bid was measured via Dual luciferase reporter assay.

RESULTS

miR-26a-5p expression was greatly decreased in HSCs and serum treated with azithromycin, simvastatin and diclofenac sodium, respectively. Hepatocyte viability was largely suppressed while hepatocyte apoptosis was markedly increased in DILI. Correspondingly, the apoptosis-associated proteins including Bid, caspase-8 and cytochrome C in HSCs were significantly upregulated when treated with either of these drugs. Moreover, miR-26a-5p interacted with Bid, and hepatocyte proliferation and apoptosis influenced by miR-26a-5p mimics were obviously reversed when co-treated with overexpressed Bid plasmids.

CONCLUSIONS

miR-26a-5p played a protective role against DILI via targeting Bid.

Drug-induced liver injury and COVID-19: A review for clinical practice

Coronavirus disease 2019 (COVID-19) consists of a systemic disease that can present many complications. The infection presents broad clinical symptoms and a high rate of transmissibility. In addition to severe acute respiratory syndrome, the patients manifest complications beyond the respiratory system. The frequency of liver damage in COVID-19 patients ranges from 14.8% to 53% of patients. One should pay attention to drug-induced liver injury (DILI) in patients with COVID-19, especially considering the off-label use of drugs in prophylactic and therapeutic regimens applied on large scales. This review aims to present relevant information on the medication used so far in COVID-19 patients and its possible hepatotoxicity. We reviewed liver damage in patients with COVID-19 on PubMed and Virtual Health Library to investigate DILI cases. Four studies were selected, involving the medicines remdesivir, tocilizumab and a pharmacovigilance analysis study. The hepatotoxicity profile of drugs presented in the literature considers use in accordance to usual posology standards for treatment. However, drugs currently used in the management of COVID-19 follow different dosages and posology than those tested by the pharmaceutical industry. The deficiency of uniformity and standardization in the assessment of hepatotoxicity cases hinders the publication of information and the possibility of comparing information among healthcare professionals. It is suggested that severe liver injury in COVID-19 patients should be reported in pharmacovigilance institutions, and physicians should pay attention to any considerable abnormal liver test elevation as it can demonstrate unknown drug hepatotoxicity. Liver disorders in COVID-19 patients and the use of several concomitant off-label medications - with a potential risk of further damaging the liver - should at least be a warning sign for rapid identification and early intervention, thus preventing liver damage from contributing to severe impairment in patients.

Microenvironment Activatable Nanoprodrug Based on Gripper-like Cyclic Phenylboronic Acid to Precisely and Effectively Alleviate Drug-induced Hepatitis

Drug-induced hepatitis (DIH), which seriously interferes with disease treatment, is one of the most common reasons for termination of new drugs during preclinical studies or post-marketing surveillance. Although antioxidants and anti-inflammatory agents are promising, their nonspecific distribution and insolubility limit their application. Therefore, precise drug release at the disease site is an important way to alleviate DIH and avoid side effects.

Methods: A gripper-like hydrophilic cyclic phenylboronic acid (cPBA) was synthesized and a nanoprodrug (cPBA-BE) was established by coupling cPBA with hydrophobic baicalein (BE). The stimuli-responsive release properties and therapeutic effect of cPBA-BE on drug-injured hepatocyte were investigated. The biodistribution and therapeutic effect of cPBA-BE both in acetaminophen-induced acute hepatitis model and rifampicin-induced chronic hepatitis model were further evaluated.

Results: cPBA-BE conjugate could self-assemble into nanoprodrug with cPBA as the hydrophilic external layer and BE as the hydrophobic core. In HepaRG cells, cPBA-BE showed stronger cellular uptake. Due to the H₂O₂- and acid-sensitivity, cPBA-BE could achieve adequate BE release, significantly resist the depletion of GSH, mitochondrial dysfunction, downregulation of inflammation and cell apoptosis in the acetaminophen injured HepaRG cells. Biodistribution showed that cPBA-BE specifically increased the concentration of BE in the liver of DIH mice. cPBA-BE could alleviate acetaminophen-induced acute hepatitis or rifampicin-induced chronic hepatitis more effectively through relieving the oxidative stress, inflammation and block the neutrophil infiltration in liver.

Conclusions: cPBA is expected to be a good platform for constructing injectable nanoprodrug with both H₂O₂ and pH-responsive properties by coupling a wide range of drugs containing o-diol. In this study, the nanoprodrug cPBA-BE was determined to be effective for alleviating the DIH.

Overview of Causality Assessment for Drug-Induced Liver Injury (DILI) in Clinical Trials

Causality assessment for suspected drug-induced liver injury (DILI) during drug development and following approval is challenging. The IQ DILI Causality Working Group (CWG), in collaboration with academic and regulatory subject matter experts (SMEs), developed this manuscript with the following objectives: (1) understand and describe current practices; (2) evaluate the utility of new tools/methods/practice guidelines; (3) propose a minimal data set needed to assess causality; (4) define best practices; and (5) promote a more structured and universal approach to DILI causality assessment for clinical development. To better understand current practices, the CWG performed a literature review, took a survey of member companies, and collaborated with SMEs. Areas of focus included best practices for causality assessment during clinical development, utility of adjudication committees, and proposals for potential new avenues to improve causality assessment. The survey and literature review provided renewed understanding of the complexity and challenges of DILI causality assessment as well as the use of non-standardized approaches. Potential areas identified for consistency and standardization included role and membership of adjudication committees, standardized minimum dataset, updated assessment tools, and best practices for liver biopsy and rechallenge in the setting of DILI. Adjudication committees comprised of SMEs (i.e., utilizing expert opinion) remain the standard for DILI causality assessment. A variety of working groups continue to make progress in pursuing new tools to assist with DILI causality assessment. The minimum dataset deemed adequate for causality assessment provides a path forward for standardization of data collection in the setting of DILI. Continued progress is necessary to optimize and advance innovative tools necessary for the scientific, pharmaceutical, and regulatory community.

Case report: Secondary sclerosing cholangitis induced by lapatinib and vinorelbine in a metastasis breast cancer patient

Secondary sclerosing cholangitis (SSC) is a rare cholestatic liver disease that may have a severe clinical course. A 61‐year‐old woman with a history of metastasis breast cancer was admitted to our hospital for the second cycle of chemotherapy with lapatinib and vinorelbine. The patient had no reports of elevated liver function tests (LFTs) in the previous multiple chemotherapies or history of liver disease. However, the admission laboratory results showed severe cholestatic liver injury with the possibility of SSC by magnetic resonance cholangiopancreatography. Although chemotherapy was discontinued and patient was treated with hepatoprotective drugs, the LFTs did not improve and liver biopsy indicated mild injury of intrahepatic bile duct epithelium and hepatocyte. We added ursodeoxycholic acid and prednisolone to protect the liver, and laboratory data showed a response. To prevent the progression, lapatinib and vinorelbine were reintroduced and transient increases in alanine aminotransferase and γ‐glutamyl transpeptidase were observed. With no evidence of viral or autoimmune liver disease, SSC induced by lapatinib and vinorelbine was diagnosed. This is the first case report of tyrosine kinase inhibitors and vinorelbine induced SSC and clinicians should be aware of the possibility of it. More case reports about this adverse drug reaction are needed to delineate optimal management.

Drug-induced liver injury: Asia Pacific Association of Study of Liver consensus guidelines

Idiosyncratic drug-induced liver injury mimics acute and chronic liver disease. It is under recognized and underrecognised because of the lack of pathognomonic diagnostic serological markers. Its consequences may vary from being asymptomatic to self-limiting illness to severe liver injury leading to acute liver failure. Its incidence is likely to be more common in Asia than other parts of the world, mainly because of hepatotoxicity resulting from the treatment of tuberculosis disease and the ubiquitous use of traditional and complimentary medicines in Asian countries. This APASL consensus guidelines on DILI is a concise account of the various aspects including current evidence-based information on DILI with special emphasis on DILI due to antituberculosis agents and traditional and complementary medicine use in Asia.

Recent Progress in Fluorescent Sensors for Drug-Induced Liver Injury Assessment

Drug-induced liver injury (DILI) is a persistent concern in drug discovery and clinical medicine. The current clinical methods to assay DILI by analyzing the enzymes in serum are still not optimal. Recent studies showed that fluorescent sensors would be efficient tools for detecting the concentration and distribution of DILI indicators with high sensitivity and specificity, in real-time, in situ, and with low damage to biosamples, as well as diagnosing DILI. This review focuses on the assessment of DILI, introduces the current mechanisms of DILI, and summarizes the design strategies of fluorescent sensors for DILI indicators, including ions, small molecules, and related enzymes. Some challenges for developing DILI diagnostic fluorescent sensors are put forward. We believe that these design strategies and challenges to evaluate DILI will inspire chemists and give them opportunities to further develop other fluorescent sensors for accurate diagnoses and therapies for other diseases.

Drug induced liver injury: an update

Drug induced liver injury (DILI) is a relatively rare hepatic condition in response to the use of medications, illegal drugs, herbal products or dietary supplements. It occurs in susceptible individuals through a combination of genetic and environmental risk factors believed to modify drug metabolism and/or excretion leading to a cascade of cellular events, including oxidative stress formation, apoptosis/necrosis, haptenization, immune response activation and a failure to adapt. The resultant liver damage can present with an array of phenotypes, which mimic almost every other liver disorder, and varies in severity from asymptomatic elevation of liver tests to fulminant hepatic failure. Despite recent research efforts specific biomarkers are not still available for routine use in clinical practice, which makes the diagnosis of DILI uncertain and relying on a high degree of awareness of this condition and the exclusion of other causes of liver disease. Diagnostic scales such as the CIOMS/RUCAM can support the causality assessment of a DILI suspicion, but need refinement as some criteria are not evidence-based. Prospective collection of well-vetted DILI cases in established DILI registries has allowed the identification and validation of a number of clinical variables, and to predict a more severe DILI outcome. DILI is also in need of properly designed clinical trials to evaluate the efficacy of new DILI treatments as well as older drugs such as ursodeoxycholic acid traditionally used to ameliorate cholestasis or corticosteroids now widely tried in the oncology field to manage the emergent type of hepatotoxicity related to immune checkpoint inhibitors.

Clinical implications of drug-induced liver injury in early-phase oncology clinical trials

BACKGROUND

Data on drug-induced liver injury (DILI) and acute liver failure (ALF) in modern phase 1 oncology trials are limited, specifically with respect to the incidence and resolution of DILI and the safety of drug rechallenge.

METHODS

This study reviewed all patients who were recruited to phase 1 oncology trials between 2013 and 2017 at Memorial Sloan Kettering Cancer Center. Clinicopathologic data were extracted to characterize DILI, and attribution was assessed on the basis of data prospectively generated during the studies. Logistic regression models were used to explore factors related to DILI and DILI recurrence after drug rechallenge.

RESULTS

Among 1670 cases recruited to 85 phase 1 trials, 81 (4.9%) developed DILI. The rate of DILI occurrence was similar for patients in immune-based trials and patients in targeted therapy trials (5.0% vs 4.9%), as was the median time to DILI (5.5 vs 6.5 weeks; P = .48). Two patients (0.12%) met the criteria of Hy's law, although none developed ALF. The DILI resolved in 96% of the patients. Pretreatment factors were not predictive for DILI development. Thirty-six of the 81 patients underwent a drug rechallenge, and 28% of these patients developed DILI recurrence. Peak alanine aminotransferase during the initial DILI was associated with DILI recurrence (odds ratio, 1.04; 95% confidence interval, 1.0-1.09; P = .035).

CONCLUSIONS

In modern phase 1 oncology trials, DILI is uncommon, may occur at any time, and often resolves with supportive measures. Rechallenging after DILI is feasible; however, the high rate of DILI recurrence suggests that clinicians should consider the severity of the DILI episode and treatment alternatives.

Incidence and Sequelae of Liver Injury Among Children Treated for Solid Tumors: Analysis of a Large Single-Center Prospective Cohort

OBJECTIVES

Pediatric oncology patients are at risk of adverse drug events. The incidence and etiologies of liver injury in this population are not well characterized. We utilized a large, single-center pediatric oncology registry to investigate the incidence, causes, and outcomes of liver injury during treatment for solid tumor malignancies.

METHODS

We reviewed all young individuals (age <25 years) who received treatment for any solid tumor at the University of Michigan between January 2004 and July 2016. Subjects with liver injury meeting predetermined laboratory criteria were identified. Cases were independently reviewed by 2 expert hepatologists to assign a cause of liver injury. Clinical characteristics of drug-induced liver injury (DILI) and non-DILI cases were compared. Cases of liver injury occurring after bone marrow or liver transplant were excluded.

RESULTS

Of 1136 solid tumor patients, 160 (14%) experienced liver injury, and the overall frequency of DILI was 4%. DILI was the leading identified cause of liver injury (31%), followed by infection (17%), metastatic/malignant biliary disease (13%), and perioperative liver injury (13%). Most DILI cases (>90%) were mild acute hepatocellular injury episodes that did not result in modification to the chemotherapy plan, and all DILI eventually resolved. Severe presentations involving jaundice and/or prolonged hospital course were significantly more common among non-DILI versus DILI cases (23% vs 2%, P < 0.001).

CONCLUSIONS

DILI is the leading cause of liver injury events among pediatric solid tumor patients. In our registry, DILI was of mild severity and did not result in an alteration of the treatment plan in most patients. In contrast, non-DILI-related liver injury events, including infection, were more likely to have a more severe presentation and a complicated course with a greater mortality during follow-up.

A sensitive upconverting nanoprobe based on signal amplification technology for real-time in situ monitoring of drug-induced liver injury

Drug-induced liver injury (DILI) is increasingly recognized as one of the most challenging global health problems. Conventional in vitro detection methods not only lack specificity and sensitivity but also cannot achieve real-time, straightforward visualization of hepatotoxicity in vivo. Liver-specific miR122 has been observed to be a superior and sensitive biomarker for DILI diagnosis. Herein, a sensitive upconverting nanoprobe synthesized with upconversion nanoparticles (UCNPs) and gold nanorods (GNR) was designed to diagnose hepatotoxicity in vivo. After injection, the nanoprobes accumulated in the liver and were activated by miR122, and the signal amplification technology fully yielded luminescent amplification; hence, the detection sensitivity was improved. Because of the high tissue penetration capability of near-infrared light, this nanoprobe can achieve real-time in situ detection, thereby providing a novel technology for precise biological and medical analysis.

Chemical probes for drug-induced liver injury imaging

Drug-induced liver injury (DILI) has been a long-standing concern of modern medicine, and the single most frequent reason for drug nonapprovals and postapproval restrictions or withdrawals. Chemical probes for early diagnosis of DILI has triggered a tremendous interest in the field of molecular imaging. In this review, we make a brief summary of the recently developed chemical probes and their applications in DILI imaging with special attention to the design of chemical probes, mechanism of their actions and their performances in DILI imaging.

A methylation functional detection hepatic cell system validates correlation between DNA methylation and drug-induced liver injury

Drug-induced liver injury (DILI) is a life-threatening, adverse reaction to certain drugs. The onset and extent of DILI can vary drastically in different patients using identical drugs. Association studies suggested that subtle differences in DNA methylation may help explain the individual differences in DILI. However, there are very few experimental methods to confirm such associations. In this study, we established a novel DNA methylation functional detection system in human hepatocytes, using CRISPR/dCas9 for targeted modification of DNA methylation, and set four parameters to indicate the liver injury by cell model. Using this system, we validated the association of hypermethylation of CYP2D6 and CYP2E1 with rifampin-induced DILI. Our results revealed that, following treatment of HepaRG cells with rifampin, the methylation levels of CYP2D6 and CYP2E1 were inversely proportional to cell viability and glutathione content, and directly proportional to caspase 3/7 activity. We expect that our methylation detection system will serve as a useful tool in validating correlations between DNA methylation and DILI in other in vitro systems. Our results establish a foundation for future investigations to better understand the mechanisms underlying DILI and may aid in advancing personalized DILI medicine.

Transcriptomic analysis reveals the mechanism of sulfasalazine-induced liver injury in mice

Liver injury is one of the main toxic effect of sulfasalazine (SASP). However, the toxicological mechanism of SASP-induced liver injury remains unclear. In the present study, the liver injury was induced by orally treatment with SASP for 4 weeks in mice. The hepatic mRNA profiles were detected by RNA sequencing and the differentially expressed genes (DEGs) were analyzed by bioinformatics methods. The elevated serum levels of alanine aminotransferase (ALT), alkaline phosphatase (ALP) and total bilirubin (TBIL), combined with the hepatic histopathological features verified that liver injury was successfully caused by SASP. Transcriptomic results showed that 187 genes (fold change > 1.5 and P < 0.05) were differentially expressed, of which 106 genes were up-regulated and 81 genes were down-regulated in SASP-treated group. Moreover, the further analysis showed that these 187 differentially expressed genes (DEGs) were enriched in 123 GO terms, which mainly including oxidation-reduction process, oxidoreductase activity and epoxygenase P450 pathway. KEGG pathway analysis showed 30 pathways including chemical carcinogenesis, retinol metabolism, arachidonic acid metabolism, linoleic acid metabolism and glutathione metabolism. Among these 187 DEGs, the top 22 hub genes were screened from network of protein-protein interaction (PPI) and verified by qRT-PCR. The results showed that the mRNA levels of hepatic drug-metabolizing enzymes, including cyp2b50, cyp2c50, cyp2c39, cyp2c38, cyp2c29, cyp2c54, cyp2c55, cyp2a5, gsta1, gsta2, gstt2, gstm2 and ephx1, were significantly up-regulated, while egfr and egr1 were down-regulated in SASP-treated group. Moreover, the mRNA levels of egfr and cyp2c55 exhibited a dose-dependent changes in SASP groups. Western blotting verified that the changes of protein levels of EGFR and CYP2C55 were consistent with mRNA levels. Considering that egfr has the highest score in PPI degree and cyp2c55 has the largest fold change in qPCR analysis, our present results suggested that the toxicological mechanisms of SASP-induced liver injury might be related to multi-biological processes and pathways, and egfr and cyp2c55 may play important roles in SASP-induced liver injury. The present study would be helpful for better understanding the hepatotoxic mechanism of SASP. However, the precise mechanism still needs further research.

Risk stratification for secondary prophylaxis of gastric varices due to portal hypertension

BACKGROUND

Gastroesophageal variceal hemorrhage is a common complication associated with portal hypertension. Current guidelines provide well-established recommendations for esophageal varices, while that of gastric varices remain scarce and lack evidential strength. The aim of the study is to identify a feasible risk stratification method based on imaging findings to evaluate patient response to cyanoacrylate injection for the treatment of gastric varices.

METHODS

A prospective cohort study including patients diagnosed with gastric varices admitted for initial secondary prophylactic treatment for GV was conducted. Routine endoscopic examination and endoscopic ultrasound (EUS) were performed on all subjects to evaluate extraluminal collaterals. All patients with gastric varices were treated uniformly with cyanoacrylate injection. Patients were prospectively followed for at least 12 months and any occurrence of variceal rebleed was recorded.

RESULTS

102 subjects were enrolled in the study, 66.7% had GOV Type 2, 27.5% had GOV Type 1 and 5.9% had IGV Type 1. During the 12 months follow-up, 33.3% patients experienced variceal rebleed. A risk assessment scoring system was proposed based on endoscopic and EUS findings. A Cox regression analysis demonstrated a significant association between the merited risk score and incidence of variceal rebleed (P < 0.001).

CONCLUSIONS

Presence of red wales sign, size of varix, and presence of para-gastric vein were all independent risk factors for variceal rebleed after endoscopic therapy for the treatment of gastric varices. Early identification of this subgroup, especially those with higher risk scores, necessitates a change in course of treatment, which can improve prognosis and overall patient outcome.

Imatinib-induced hepatitis treated by corticosteroids in a patient with metastatic gastrointestinal stromal tumor

Imatinib mesylate is currently used as the first-line treatment for metastatic gastrointestinal stromal tumors (GISTs). Imatinib-induced hepatotoxicity in patients with GIST is very rare. Its features vary from subclinical elevation of serum aminotransferase to clinically apparent acute hepatitis, which is associated with immunologic reactions. Imatinib-induced hepatotoxicity with autoimmune-like features can be treated by the discontinuation of imatinib mesylate and the administration of oral steroids. Here, we report a case of late-onset imatinib-induced hepatitis with autoimmune-like features in a patient with metastatic GIST, which was improved by oral corticosteroids.

Metabolic Comorbidities and Risk of Development and Severity of Drug-Induced Liver Injury

The incidence and rates of diagnosis of drug-induced liver injury (DILI) have been increasing in recent years as findings from basic research and the examination of clinical databases reveal information about the clinical course, etiology, and prognosis of this complex disease. The prevalence of metabolic comorbidities (e.g., diabetes mellitus, fatty liver, obesity, and metabolic syndrome (MetS)) has been increasing during the same period. The results of preclinical and clinical research studies indicate that characteristics of metabolic comorbidities are also factors that affect DILI phenotype and progression. The objective of this review is to present the evidence for DILI and hepatotoxicity mechanisms, incidence, and outcomes in patients with MetS and nonalcoholic fatty liver disease. Moreover, we also summarize the relationships between drugs used to treat metabolic comorbidities and DILI.

Mechanistic Studies of Idiosyncratic DILI: Clinical Implications

The idiosyncratic nature of idiosyncratic drug-induced liver injury (IDILI) makes mechanistic studies very difficult, and little is known with certainty. However, the fact that the IDILI caused by some drugs is associated with specific HLA genotypes provides strong evidence that it is mediated by the adaptive immune system. This is also consistent with the histology and the general characteristics of IDILI. However, there are other mechanistic hypotheses. Various in vitro and in vivo systems have been used to test hypotheses. Two other hypotheses are mitochondrial injury and inhibition of the bile salt export pump. It is possible that these mechanisms are responsible for some cases of IDILI or that these mechanisms are complementary and are involved in initiating an immune response. In general, it is believed that the initiation of an immune response requires activation of antigen-presenting cells by molecules such as danger-associated molecular pattern molecules (DAMPs). An attractive hypothesis for the mechanism by which DAMPs induce an immune response is through the activation of inflammasomes. The dominant immune response in the liver is immune tolerance, and it is only when immune tolerance fails that significant liver injury occurs. Consistent with this concept, an animal model was developed in which immune checkpoint inhibition unmasked the ability of drugs to cause liver injury. Although it appears that the liver damage is mediated by the adaptive immune system, an innate immune response is required for an adaptive immune response. The innate immune response is not dependent on specific HLA genes or T cell receptors and may occur in most patients and animals treated with a drug that can cause IDILI. Studies of the subclinical innate immune response to drugs may provide important mechanistic clues and provide a method to screen drugs for their potential to cause IDILI.