The safety of stopping nucleos(t)ide analogue treatment in patients with HBeAg-negative chronic hepatitis B

Safety considerations for withdrawal of nucleos(t)ide analogues in patients with chronic hepatitis B: First, do no harm

Nucleos(t)ide analogues (NA) are widely used to treat hepatitis B virus (HBV) infection, but they cannot eradicate the virus and treatment duration can be lifelong if the endpoint is set at seroclearance of the hepatitis B surface antigen (HBsAg). As an alternative strategy, finite NA therapy without the prerequisite of HBsAg seroclearance has been proposed to allow treatment cessation in patients with sustained undetectable HBV viremia for two to three years. However, reactivation of viral replication almost always follows NA withdrawal. Whereas HBV reactivation might facilitate HBsAg seroclearance in some, it could lead to serious acute flare-ups in a certain proportion of patients. Occurrence and consequences of NA withdrawal flares are complicated with various factors involving the virus, host, and treatment. Accurate risk prediction for severe flares following NA cessation is essential to ensure patient safety. The risks of life-threatening flares in patients who discontinued NA according to the stopping rules of current guidelines or local reimbursement policies have recently been quantitatively estimated in large-scale studies, which also provided empirical evidence to help identify vulnerable patients at risk of devastating outcomes. Moreover, risk predictors were further explored and validated to hopefully aid in patient selection and management. In this narrative review with a focus on patient safety, we summarize and discuss current literature on the incidence of severe flares following NA cessation, risk stratification for candidate selection, rules of posttreatment monitoring, and indications for treatment resumption. We also share our thoughts on the limitations of existing knowledge and suggestions for future research.

Genetics are not likely to offer clinically useful predictions for elevated liver enzyme levels in patients using low dose methotrexate

OBJECTIVE

To examine genetic influence on the risk of elevations in liver function tests (AST and ALT) among patients using low-dose methotrexate (LD-MTX).

METHODS

We examined data from the LD-MTX arm of a randomized double-blind placebo-controlled trial conducted among subjects without rheumatic disease. Genome wide association studies (GWAS) were performed in subjects of European ancestry to test the association between single nucleotide polymorphisms (SNPs) and the log transformed maximum values of AST, ALT, and dichotomized outcome with AST or ALT > 2 times upper limit of normal (ULN). The association between variants in MTX metabolism candidate genes and the outcomes was also tested. Furthermore, associations between a drug induced liver injury (DILI) weighted genetic risk score (wGRS) and the outcomes were tested, combining 10 SNPs and 11 classical HLA alleles associated with DILI.

RESULTS

In genome-wide genetic analyses among 1,429 subjects of European ancestry who were randomized to receive LD-MTX, two SNPs reached genome wide significance for association with log transformed maximum ALT. We observed associations between established candidate genes in MTX pharmacogenetics and log transformed maximum AST and ALT, as well as in dichotomized outcome with AST or ALT > 2 x ULN. There was no association between DILI wGRS or candidate variants and AST, ALT, or DILI response.

CONCLUSIONS

Modest evidence was observed that common variants affected AST and ALT levels in subjects of European ancestry on LD-MTX, but this genetic effect is not useful as a clinical predictor of MTX toxicity.

How to achieve functional cure of HBV: Stopping NUCs, adding interferon or new drug development?

Functional cure of hepatitis B is defined as sustained undetectable circulating HBsAg and HBV DNA after a finite course of treatment. Barriers to HBV cure include the reservoirs for HBV replication and antigen production (covalently closed circular DNA [cccDNA] and integrated HBV DNA), the high viral burden (HBV DNA and HBsAg) and the impaired host innate and adaptive immune responses against HBV. Current HBV therapeutics, 1 year of pegylated-interferon-α (PEG-IFNα) and long-term nucleos(t)ide analogues (NUCs), rarely achieve HBV cure. Stopping NUC therapy may lead to functional cure in some Caucasian patients but rarely in Asian patients. Switching from a NUC to IFN after HBV DNA suppression increases the chance of HBsAg clearance mainly in those with low HBsAg levels. Novel antiviral strategies that inhibit viral entry, translation and secretion of HBsAg, modulate capsid assembly, or target cccDNA transcription/degradation have shown promise in clinical trials. Novel immunomodulatory approaches including checkpoint inhibitors, metabolic modulation of T cells, therapeutic vaccines, adoptive transfer of genetically engineered T cells, and stimulation of innate and B-cell immune responses are being explored. These novel approaches may be further combined with NUCs or PEG-IFNα in personalised strategies, according to virologic and disease characteristics, to maximise the chance of HBV cure. The development of curative HBV therapies should be coupled with the development of standardised and validated virologic and immunologic assays to confirm target engagement and to assess response. In addition to efficacy, curative therapies must be safe and affordable to meet the goal of global elimination of hepatitis B.

Management of hepatitis B virus reactivation due to treatment of COVID-19

The world has made significant progress in developing novel treatments for COVID-19 since the pandemic began. Some treatments target the patient's dysregulated inflammatory response during COVID-19 infection and may cause hepatitis B reactivation (HBVr) in patients with current or past hepatitis B virus (HBV) infection. This review summarizes the risk and management of HBVr due to different treatments of COVID-19 in patients who have current or past HBV infection. Abnormal liver function tests are common during COVID-19 infection. Current evidence suggests that current or past HBV infection is not associated with an increased risk of liver injury and severe disease in COVID-19 patients. Among patients who received high-dose corticosteroids, various immunosuppressive monoclonal antibodies and inhibitors of Janus kinase, the risk of HBVr exists, especially among those without antiviral prophylaxis. Data, however, remain scarce regarding the specific use of immunosuppressive therapies in COVID-19 patients with HBV infection. Some results are mainly extrapolated from patients receiving the same agents in other diseases. HBVr is a potentially life-threatening event following profound immunosuppression by COVID-19 therapies. Future studies should explore the use of immunosuppressive therapies in COVID-19 patients with HBV infection and the impact of antiviral prophylaxis on the risk of HBVr.

COVID-19 and hepatitis B infection

The 2019 coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged as a major burden worldwide, resulting in serious public health challenges. HBV infection is another widely spread virus that chronically affects about 257 million people. The management of patients with HBV infection has gained attention in the context of the COVID-19 pandemic. Patients with COVID-19 have varying levels of liver involvements, resulting from direct viral effects on the liver as well as hepatotoxic drugs. This was demonstrated by elevated levels of liver enzymes, particularly evident in those patients with severe SARS-CoV-2 infection. However, scarce information is available on the management of COVID-19 patients having an underlying chronic liver disease, including HBV infection. Studies have shown reactivation of HBV infection following treatment with tocilizumab and corticosteroids, emphasizing the need for caution when using these agents to treat COVID-19 patients with HBV infection. HBV screening and prophylaxis should be considered in patients with elevated transaminase levels and also in high prevalence populations. In patients with advanced liver disease, attention must be given to minimize the risk of liver decompensation. Nevertheless, further investigation is needed to enable an evidence-based approach for the care of these patients.

Transaminase Elevations during Treatment of Chronic Hepatitis B Infection: Safety Considerations and Role in Achieving Functional Cure

While current therapies for chronic HBV infection work well to control viremia and stop the progression of liver disease, the preferred outcome of therapy is the restoration of immune control of HBV infection, allowing therapy to be removed while maintaining effective suppression of infection and reversal of liver damage. This “functional cure” of chronic HBV infection is characterized by the absence of detectable viremia (HBV DNA) and antigenemia (HBsAg) and normal liver function and is the goal of new therapies in development. Functional cure requires removal of the ability of infected cells in the liver to produce the hepatitis B surface antigen. The increased observation of transaminase elevations with new therapies makes understanding the safety and therapeutic impact of these flares an increasingly important issue. This review examines the factors driving the appearance of transaminase elevations during therapy of chronic HBV infection and the interplay of these factors in assessing the safety and beneficial nature of these flares.

Hepatitis B surface antigen, core-related antigen and HBV RNA: Predicting clinical relapse after NA therapy discontinuation

BACKGROUND & AIMS

The safe discontinuation of nucleos(t)ide analogue therapy remains challenging in chronic hepatitis B. We investigated the potential role of quantitative hepatitis B surface antigen, hepatitis B core-related antigen and hepatitis B virus RNA at the end of treatment in predicting off-therapy relapse.

METHODS

Patients who fulfilled the stopping criteria of the Asian Pacific Association for the Study of the Liver guideline were enrolled. Virological relapse was defined as hepatitis B virus DNA level greater than 2000 IU/mL, and clinical relapse was defined as virological relapse plus alanine aminotransferase level of more than twice the upper limit of normal.

RESULTS

Ninety-two patients participated. The combination of end-of-treatment hepatitis B core-related antigen and hepatitis B virus RNA levels was most predictive of clinical relapse. Multivariate analysis revealed that end-of-treatment hepatitis B core-related antigen and hepatitis B virus RNA were independently associated with clinical relapse. During follow-up, no patients with undetectable hepatitis B core-related antigen (<3.0 log₁₀ U/mL) and hepatitis B virusRNA (<2.0 log₁₀ copies/mL) at end of treatment developed clinical relapse, in comparison with 22.9% and 62.5% patients with detectable levels of one or both biomarkers respectively. End-of-treatment quantitative hepatitis B surface antigen was linked to a likelihood of hepatitis B surface antigen clearance.

CONCLUSIONS

The combined hepatitis B core-related antigen and hepatitis B virus RNA assays at end of treatment were highly predictive of subsequent clinical relapse. These novel biomarkers could potentially be used to identify patients who could safely discontinue nucleos(t)ide analogue therapy.

Management of patients with liver derangement during the COVID-19 pandemic: an Asia-Pacific position statement

The COVID-19 pandemic has spread rapidly worldwide. It is common to encounter patients with COVID-19 with abnormal liver function, either in the form of hepatitis, cholestasis, or both. The clinical implications of liver derangement might be variable in different clinical scenarios. With growing evidence of its clinical significance, it would be clinically helpful to provide practice recommendations for various common clinical scenarios of liver derangement during the COVID-19 pandemic. The Asia-Pacific Working Group for Liver Derangement during the COVID-19 Pandemic was formed to systematically review the literature with special focus on the clinical management of patients who have been or who are at risk of developing liver derangement during this pandemic. Clinical scenarios covering the use of pharmacological treatment for COVID-19 in the case of liver derangement, and assessment and management of patients with chronic hepatitis B or hepatitis C, non-alcoholic fatty liver disease, liver cirrhosis, and liver transplantation during the pandemic are discussed.