Immunotherapy and Gene Therapy: New Challenges in the Diagnosis and Management of Drug-Induced Liver Injury

Initial clinical experience with durvalumab plus tremelimumab in patients with unresectable hepatocellular carcinoma in real‑world practice

Although durvalumab plus tremelimumab (Dur/Tre) has been approved as first-line therapy for patients with unresectable hepatocellular carcinoma (u-HCC), its outcomes in real-world clinical practice are unclear. The present study aimed to evaluate the efficacy and safety of Dur/Tre treatment. This multicenter study was conducted between March 2023 and January 2024, and included 120 patients with u-HCC treated with Dur/Tre. Among the patients, 44 had no history of systemic treatment. Progression-free survival (PFS), therapeutic response and adverse events (AEs) were assessed. The objective response rate (ORR) and disease control rates (DCR) were 15.8 and 53.3%, respectively. The median PFS was 3.9 months. The incidence rates of AEs of any grade and those grade 3 or higher were 83.3 and 36.7%, respectively. Liver injury was the most frequent AE of any grade and grade 3 or higher. Although there was no significant difference in ORR and PFS between the first and later line groups (ORR 15.8 vs. 15.7%, P=0.986; PFS 4.5 vs. 3.6 months, P=0.213), there was a significant difference in DCR between the two groups (65.8 vs. 45.9%, P=0.034). No significant differences were noted between the first- and later-line treatment groups regarding the incidence rate of AEs. Decision tree analysis revealed that poor liver function and advanced age were significant variables for discontinuation owing to AEs. In conclusion, Dur/Tre as first-line therapy had better disease control responses compared with later-line therapy; however, this regimen should be carefully administered to patients with deteriorating hepatic function or advanced age.

The ABC of Immune-Mediated Hepatitis during Immunotherapy in Patients with Cancer: From Pathogenesis to Multidisciplinary Management

Immune-mediated hepatotoxicity (IMH) is not-so-rare complication during treatment with immune checkpoint inhibitors (ICIs). This narrative review aims to report the current knowledge on hepatic immune-related adverse events (irAEs) during immunotherapy from pathogenesis to multidisciplinary management. The majority of cases of IMH are asymptomatic and only a few patients may have clinical conditions. The severity of IMH is usually stratified according to Common Terminology for Clinical Adverse Events (CTCAE) criteria, but these scores may overestimate the clinical severity of IMH compared to the Drug-Induced Liver Injury Network (DILIN) scale. The differential diagnosis of IMH is challenging because the elevated liver enzymes can be due to a number of etiologies such as viral infection, autoimmune and metabolic diseases, liver metastases, biliary diseases, and other drugs. The cornerstones of IMH management are represented by withholding or delaying ICI administration and starting immunosuppressive therapy. A multidisciplinary team, including oncologists, hepatologists, internists, and emergency medicine physicians, is essential for the management of IMH.

The changes of gut microbiota and metabolites in different drug-induced liver injuries

The increasing incidence of drug-induced liver injury (DILI) has become a major concern. Gut microbiota, as another organ of the human body, has been studied in various tumors, cardiovascular metabolic diseases, inflammatory bowel disease and human immunity. The studies mentioned above have confirmed its important impact on the occurrence and development of DILI. The gut-liver axis explains the close relationship between the gut and the liver, and it may be a pathway by which gut microbes contribute to DILI. In addition, the interaction between drugs and gut microbes affects both separately, which in turn may have positive or negative effects on the body, including DILI. There are both common and specific changes in liver injury caused by different drugs. The alteration of metabolites in DILI is also a new direction of therapeutic exploration. The application of microbiomics, metabolomics and other multi-omics to DILI has also explored new ideas for DILI. In this review, we conclude the alterations of gut microbes and metabolites under different DILI, and the significance of applying gut microbiome-metabolomics to DILI, so as to explore the metabolic characteristics of DILI and possible novel metabolic biomarkers.

Effectiveness of immunosuppressant use for the treatment of immune checkpoint inhibitor-induced liver injury: A systematic review and meta-analysis

Background

Immune-mediated liver injury caused by checkpoint inhibitors (ILICI) is a challenging clinical management issue. Although immunosuppressants are widely used to manage ILICI, no large-scale studies have proved definitive evidence for the most effective form of patient management.

Aim

Analysis of the effectiveness of immunosuppression for immune-related liver injury.

Methods

We performed a systematic review and meta-analysis of the clinical outcomes of immunosuppressive treatment of ILICI patients. A literature search of PubMed, Ovid, and Cochrane Library was completed for dates from 2000 to January 1, 2022. The primary outcome was the response rate to immunosuppressive therapy for ILICI, with subgroup analysis based on the type of cancer, immune checkpoint inhibitor regimen, and severity of liver injury. The secondary outcome was the median time to recovery from ILICI with immunosuppressive therapy.

Results

A total of 30 studies that included 1120 patients were collected. The pooled ILICI response rate was 79% (95% CI 0.73-0.84) for treatment with corticosteroids and 93% (95% CI 0.79-1.0) for treatment with mycophenolate mofetil. For ILICI treated with corticosteroids, the median recovery time was 47.59 (95% CI 39.79-55.40) days compared to 37.74 (95% CI 31.12-44.35) days for all forms of immunosuppression.

Conclusion

Findings support the effectiveness of corticosteroids and mycophenolate mofetil for the treatment of ILICI. The identified median time to recovery is a beneficial guide for patients and physicians, allowing for realistic expectations and appropriate treatment management. Future prospective randomized controlled trials are required to define a standardized management approach to immunosuppressive therapy of ILICI.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022313454.

Treatment of Drug-Induced Liver Injury

Current pharmacotherapy options of drug-induced liver injury (DILI) remain under discussion and are now evaluated in this analysis. Needless to say, the use of the offending drug must be stopped as soon as DILI is suspected. Normal dosed drugs may cause idiosyncratic DILI, and drugs taken in overdose commonly lead to intrinsic DILI. Empirically used but not substantiated regarding efficiency by randomized controlled trials (RCTs) is the intravenous antidote treatment with N-acetylcysteine (NAC) in patients with intrinsic DILI by N-acetyl-p-aminophenol (APAP) overdose. Good data recommending pharmacotherapy in idiosyncratic DILI caused by hundreds of different drugs are lacking. Indeed, a recent analysis revealed that just eight RCTs have been published, and in only two out of eight trials were DILI cases evaluated for causality by the worldwide used Roussel Uclaf Causality Assessment Method (RUCAM), representing overall a significant methodology flaw, as results of DILI RCTs lacking RUCAM are misleading since many DILI cases are known to be attributable erroneously to nondrug alternative causes. In line with these major shortcomings and mostly based on anecdotal reports, glucocorticoids (GCs) and other immuno-suppressants may be given empirically in carefully selected patients with idiosyncratic DILI exhibiting autoimmune features or caused by immune checkpoint inhibitors (ICIs), while some patients with cholestatic DILI may benefit from ursodeoxycholic acid use; in other patients with drug-induced hepatic sinusoidal obstruction syndrome (HSOS) and coagulopathy risks, the indication for anticoagulants should be considered. In view of many other mechanistic factors such as the hepatic microsomal cytochrome P450 with a generation of reactive oxygen species (ROS), ferroptosis with toxicity of intracellular iron, and modification of the gut microbiome, additional therapy options may be available in the future. In summation, stopping the offending drug is still the first line of therapy for most instances of acute DILI, while various therapies are applied empirically and not based on good data from RCTs awaiting further trials using the updated RUCAM that asks for strict exclusion and inclusion details like liver injury criteria and provides valid causality rankings of probable and highly probable grades.

Highlights of the drug-induced liver injury literature for 2021

INTRODUCTION

In 2021, over 3,000 articles on Drug-Induced Liver Injury (DILI) were published, nearly doubling the annual number compared to 2011. This review selected DILI articles from 2021 we felt held the greatest interest and clinical relevance.

AREAS COVERED

A literature search was conducted using PubMed between 1 March 2021 and 28 February 2022. 86 articles were included. This review discusses new and established cases of hepatotoxins, including new FDA approvals and COVID-19 therapeutics. Developments in biomarkers and causality assessment methods are discussed. Updates from registries are also explored.

EXPERT OPINION

DILI diagnosis and prognostication remain challenging. Roussel Uclaf Causality Assessment Method (RUCAM) is the best option for determining causality and has been increasingly accepted by clinicians. Revised Electronic Causality Assessment Method (RECAM) may be more user-friendly and accurate but requires further validation. Quantitative systems pharmacology methods, such as DILIsym, are increasingly used to predict hepatotoxicity. Oncotherapeutic agents represent many newly approved and described causes of DILI. Such hepatotoxicity is deemed acceptable relative to the benefit these drugs offer. Drugs developed for non-life-threatening disorders may not show a favorable benefit-to-risk ratio and will be more difficult to approve. As the COVID-19 landscape evolves, its effect on DILI deserves further investigation.