Hepatotoxicity Induced by Biological Agents: Clinical Features and Current Controversies

Metabolic dysfunction-associated steatotic liver disease and cardiovascular risk factors in rheumatoid arthritis

OBJECTIVES

Rheumatoid arthritis (RA) is a chronic autoimmune disease linked with metabolic dysfunction-associated steatotic liver disease (MASLD), which may increase cardiovascular (CV) risk. This study explores the association between liver fibrosis, assessed by the Fibrosis-4 (FIB-4) index, and CV risk factors in RA patients.

METHODS

Cross-sectional data from the Franciscus Rheumatoid Arthritis and Cardiovascular Intervention Study (FRANCIS), a randomized, cardiovascular single center, intervention study involving RA patients without cardiovascular disease (CVD) or type 2 diabetes (T2DM), were analyzed. Liver fibrosis was assessed using FIB-4, with a cut-off point of ≥ 1.3 to define high fibrosis risk, and its relationship with CV risk factors, medication use, and subclinical atherosclerosis, measured by carotid intima-media thickness (cIMT), was evaluated.

RESULTS

Among 326 patients (68.4% female, age 53 ± 11 years, BMI 26.5 ± 4.5 kg/m2), those with high FIB-4 (n = 49) had higher cIMT (p = 0.002), apolipoprotein B48 (p = 0.04), systolic blood pressure (p = 0.007), alkaline phosphatase (p = 0.002), and anti-CCP levels (p = 0.02). High FIB-4 was associated with lower leukocyte count and complement component 3. Statin use was linked to higher FIB-4 (OR = 4.49, p = 0.014), while hydroxychloroquine use was associated with lower FIB-4 (OR = 0.11, p = 0.004). Disease activity scores did not differ between low and high FIB-4 groups.

CONCLUSIONS

Elevated FIB-4 in RA patients is associated with increased cIMT, higher blood pressure, and elevated atherogenic remnants. Incorporating FIB-4 measurements into routine clinical care for RA populations could effectively identify individuals at the highest CV risk, enabling the implementation of more intensive CV risk management strategies. Key Points • RA patients with liver fibrosis have higher cIMT, indicating greater risk of atherosclerosis. • RA patients with liver fibrosis show accumulation of circulating atherogenic chylomicron remnants, contributing to atherogenesis. • HCQ may provide a protective effect against liver fibrosis in RA patients.

Clinical Manifestations and Risk Factors of Liver Injury Induced by PD-1 Inhibitors in Patients with Malignancies: A Case-Control Study

Background

Hepatic injury induced by immune checkpoint inhibitors (ICPIs) is an inevitable challenge in the era of innovative anti-tumor therapies. However, studies on immune-related liver injury are relatively insufficient, and the associated risk factors are still lacking. The purpose of this study was to explore the incidence and clinical manifestations of immunotherapy-related liver injury.

Methods

A retrospective case-control study was conducted involving patients treated with PD-1 inhibitors at Weifang People's Hospital, a tertiary general hospital in China, from January 1, 2021 and July 31, 2024. Univariate and multivariate logistic regression analyses were employed to identify the potential risk factors. Then, the predictive value of these risk factors was evaluated using receiver operating characteristic (ROC) curve analysis.

Results

In total, 300 patients were included. Among these patients, 52 patients experienced liver injury. The mean time from the initiation of immunotherapy to the onset of liver injury was 28.4 days, with a range from 2 to 219 days. 71.15% of patients developed liver injury within the first 30 days. 82.69% presented with mild cases (grade 1), 13.46% with moderate cases (grade 2), and 3.84% with severe cases (grades 3-4). The overall incidence of PD-1 inhibitors-related liver injury was 0.34%. Specifically, nivolumab exhibited the highest incidence at 2.86%, followed by sintilimab at 0.41%. Both toripalimab and camrelizumab exhibited an incidence of 0.34%, while tislelizumab had the lowest at 0.28%. Multivariate logistic regression analysis showed that GGT and AST were independent risk factors for liver injury. ROC curve analysis revealed that patients with baseline ALT≥19.5 U/L, AST≥19.5 U/L, and GGT≥28.5 U/L were at increased risk of developing liver injury.

Conclusion

In clinical therapy, close monitoring of liver function is recommended, especially for patients with baseline ALT≥19.5 U/L, AST≥19.5 U/L, and GGT≥28.5 U/L during immunotherapy with PD-1 inhibitors.

4-Methylumbelliferone, an Inhibitor of Hyaluronan Synthase, Prevents the Development of Oncological, Inflammatory, Degenerative, and Autoimmune Diseases

Hyaluronic acid (HA) is the main structure-forming polymer of the extracellular matrix. HA metabolism plays an important role in intercellular interaction in healthy organism and in various pathologies. HA is synthesized by hyaluronan synthase (HAS); mammals have three highly homologous isoforms of this enzyme: HAS1, HAS2, and HAS3. No highly specific competitive inhibitors of HASs have been described so far. 4-Methylumbelliferone (4-MU), a natural coumarin compound, is commonly used to inhibit HA synthesis in vivo and in cell cultures. The review is focused on the molecular mechanisms underlying the therapeutic effects of 4-MU and discusses results of 4-MU application in tissue cultures and animal disease models, as well as in first clinical trials of this compound. It was found that along with receptors and transcription factors, one of the pharmacological targets of 4-MU is HAS2, which is most common isoform of HAS. Moreover, it is inhibition of HA synthesis that underlies the pharmacological effects of 4-MU in oncological, autoimmune, degenerative, and hypercompensated regenerative processes (fibrosis, scar formation). New clinical drugs based on specific HAS2 inhibitors will be the first-in-class compounds to treat a wide range of diseases.

Beyond the hype and toward application: liver complex in vitro models in preclinical drug safety

INTRODUCTION

Drug induced Liver-Injury (DILI) is a leading cause of drug attrition and complex in vitro models (CIVMs), including three dimensional (3D) spheroids, 3D bio printed tissues and flow-based systems, could improve preclinical prediction. Although CIVMs have demonstrated good sensitivity and specificity in DILI detection their adoption remains limited.

AREAS COVERED

This article describes DILI, the challenges with its prediction and the current strategies and models that are being used. It reviews data from industry-FDA collaborations and strategic partnerships and finishes with an outlook of CIVMs in preclinical toxicity testing. Literature searches were performed using PubMed and Google Scholar while product information was collected from manufacturer websites.

EXPERT OPINION

Liver CIVMs are promising models for predicting DILI although, a decade after their introduction, routine use by the pharmaceutical industry is limited. To accelerate their adoption, several industry-regulator-developer partnerships or consortia have been established to guide the development and qualification. Beyond this, liver CIVMs should continue evolving to capture greater immunological mimicry while partnering with computational approaches to deliver systems that change the paradigm of predicting DILI.

Comprehensive approaches to preclinical evaluation of monoclonal antibodies and their next-generation derivatives

Biotherapeutics hold great promise for the treatment of several diseases and offer innovative possibilities for new treatments that target previously unaddressed medical needs. Despite successful transitions from preclinical to clinical stages and regulatory approval, there are instances where adverse reactions arise, resulting in product withdrawals. As a result, it is essential to conduct thorough evaluations of safety and effectiveness on an individual basis. This article explores current practices, challenges, and future approaches in conducting comprehensive preclinical assessments to ensure the safety and efficacy of biotherapeutics including monoclonal antibodies, toxin-conjugates, bispecific antibodies, single-chain antibodies, Fc-engineered antibodies, antibody mimetics, and siRNA-antibody/peptide conjugates.

Overview of the immunological mechanisms in hepatitis B virus reactivation: Implications for disease progression and management strategies

Hepatitis B virus (HBV) reactivation is a clinically significant challenge in disease management. This review explores the immunological mechanisms underlying HBV reactivation, emphasizing disease progression and management. It delves into host immune responses and reactivation's delicate balance, spanning innate and adaptive immunity. Viral factors' disruption of this balance, as are interactions between viral antigens, immune cells, cytokine networks, and immune checkpoint pathways, are examined. Notably, the roles of T cells, natural killer cells, and antigen-presenting cells are discussed, highlighting their influence on disease progression. HBV reactivation's impact on disease severity, hepatic flares, liver fibrosis progression, and hepatocellular carcinoma is detailed. Management strategies, including anti-viral and immunomodulatory approaches, are critically analyzed. The role of prophylactic anti-viral therapy during immunosuppressive treatments is explored alongside novel immunotherapeutic interventions to restore immune control and prevent reactivation. In conclusion, this comprehensive review furnishes a holistic view of the immunological mechanisms that propel HBV reactivation. With a dedicated focus on understanding its implications for disease progression and the prospects of efficient management strategies, this article contributes significantly to the knowledge base. The more profound insights into the intricate interactions between viral elements and the immune system will inform evidence-based approaches, ultimately enhancing disease management and elevating patient outcomes. The dynamic landscape of management strategies is critically scrutinized, spanning anti-viral and immunomodulatory approaches. The role of prophylactic anti-viral therapy in preventing reactivation during immunosuppressive treatments and the potential of innovative immunotherapeutic interventions to restore immune control and proactively deter reactivation.

Immuno-inflammatory in vitro hepatotoxicity models to assess side effects of biologicals exemplified by aldesleukin

Introduction

Hepatotoxicity induced by immunotherapeutics is an appearing cause for immune-mediated drug-induced liver injury. Such immuno-toxic mechanisms are difficult to assess using current preclinical models and the incidence is too low to detect in clinical trials. As hepatotoxicity is a frequent reason for post-authorisation drug withdrawal, there is an urgent need for immuno-inflammatory in vitro models to assess the hepatotoxic potential of immuno-modulatory drug candidates. We developed several immuno-inflammatory hepatotoxicity test systems based on recombinant human interleukin-2 (aldesleukin).

Methods

Co-culture models of primary human CD8+ T cells or NK cells with the hepatocyte cell line HepaRG were established and validated with primary human hepatocytes (PHHs). Subsequently, the HepaRG model was refined by increasing complexity by inclusion of monocyte-derived macrophages (MdMs). The main readouts were cytotoxicity, inflammatory mediator release, surface marker expression and specific hepatocyte functions.

Results

We identified CD8+ T cells as possible mediators of aldesleukin-mediated hepatotoxicity, with MdMs being implicated in increased aldesleukin-induced inflammatory effects. In co-cultures of CD8+ T cells with MdMs and HepaRG cells, cytotoxicity was induced at intermediate/high aldesleukin concentrations and perforin was upregulated. A pro-inflammatory milieu was created measured by interleukin-6 (IL-6), c-reactive protein (CRP), interferon gamma (IFN-γ), and monocyte chemoattractant protein-1 (MCP-1) increase. NK cells responded to aldesleukin, however, only minor aldesleukin-induced cytotoxic effects were measured in co-cultures. Results obtained with HepaRG cells and with PHHs were comparable, especially regarding cytotoxicity, but high inter-donor variations limited meaningfulness of the PHH model.

Discussion

The in vitro test systems developed contribute to the understanding of potential key mechanisms in aldesleukin-mediated hepatotoxicity. In addition, they may aid assessment of immune-mediated hepatotoxicity during the development of novel immunotherapeutics.

Reversing the Inflammatory Process-25 Years of Tumor Necrosis Factor-α Inhibitors

Immune-mediated inflammatory diseases, such as rheumatoid arthritis, psoriatic arthritis, peripheral and/or axial spondyloarthritis, Crohn's disease, and ulcerative colitis, are characterized by molecular and cellular changes in the immune system. Due to the systemic nature of these diseases, organs such as the liver or cardiovascular system are often affected by the inflammatory process. Tumor necrosis factor-α inhibitor therapy reduces the activation of pro-inflammatory signaling cascades, mitigates the chronic inflammatory process by restoring cellular balance, and alleviates clinical consequences, such as pain and tissue damage.

Drug-Induced Liver Injury due to Biologics and Immune Check Point Inhibitors

Biological agents have in the last two decades become very important therapeutic agents, particularly for the treatment of various autoimmune disorders. The most widely used biologics are the tumor necrosis factor-α (TNF-α) receptor antagonists: infliximab, adalimumab, and etanercept. Other commonly used biological agents are interleukin (IL)-1 receptor antagonist (Anakinra), interleukin (IL)-6 receptor antagonist (tocilizumab), and CD20 surface antigen antagonist (rituximab). The current review will however focus on TNF-α receptor antagonists.

Checkpoint inhibitor-induced hepatotoxicity: Role of liver biopsy and management approach

Immunological checkpoint inhibitors (ICIs) have revolutionized therapy of many different malignanices. Concomitant immune-mediated adverse effects are common and can affect many organs such as the skin, lungs, gastrointestinal and endocrine organs as well as the liver. Liver injury has been reported in 3%-8% of patients with grade III-IV hepatitis in retrospective studies. The liver injury is characterized by hepatocellular injury resembling autoimmune hepatitis biochemically but not immunologically as patients with ICI induced hepatoxicity rarely have auto-antibodies or IgG elevation. The role for liver biopsy (LB) in patients with suspected liver injury due to ICIs is controversial and it is not clear whether results of a LB will change clinical management. LB can be helpful when there is diagnostic uncertainty and pre-existing liver disease is suspected. Although there are no distinctive histological features, the finding of granulomas and endothelitis may suggest a specific type of hepatitis induced by ICIs. The natural history of hepatotoxicity of ICI therapy is not well known. Recent studies have demonstrated that 33%-50% of patients improve spontaneously with discontinuation of ICIs. In patients with jaundice and/or coagulopathy corticosteroids are used. The high doses of corticosteroids with 1-2 mg/kg/d of methylprednisolone recommended by the oncological societies are controversial. Recently it has shown that initial treatment with 1 mg/kg/d provided similar liver tests improvement which was also associated with a reduced risk of steroid-induced adverse effects in comparison with higher-dose regimens. Secondary immunosuppression mostly with mycophenolate mofetil has been reported to be helpful.