Severe Acute Exacerbation After Cessation of Nucleos(t)ide Analog for Chronic Hepatitis B: A Real-World Study of Routine Practice

"Treat-all" Strategy for Patients with Chronic Hepatitis B Virus Infection in China: Are We There Yet?

Chronic hepatitis B remains the primary cause of liver-related events in China. The World Health Organization set a goal to eliminate viral hepatitis as a public health threat by 2030. However, achieving this goal appears challenging due to the current low rates of diagnosis and treatment. The "Treat-all" strategy, which proposes treating all patients with detectable hepatitis B virus (HBV) DNA or even all patients with positive HBsAg, has been suggested to simplify anti-HBV treatment. In 2022, the Chinese Society of Hepatology and the Chinese Society of Infectious Diseases updated the guidelines for the prevention and treatment of chronic hepatitis B in China, expanding antiviral indications and simplifying the treatment algorithm. According to this latest guideline, nearly 95% of patients with detectable HBV DNA are eligible for antiviral treatment. This review aimed to provide a detailed interpretation of the treatment indications outlined in the Chinese Guidelines for the Prevention and Treatment of Chronic Hepatitis B (version 2022) and to identify gaps in achieving the "Treat-all" strategy in China.

Discontinuation of Nucleos(t)ide Analogues in HBeAg Negative Chronic Hepatitis B Patients: Risks and Benefits

Chronic hepatitis B (CHB) remains a major threat to global public health, affecting 296 million people worldwide. Although there is no curative treatment for CHB today, the virus can be effectively controlled with current antiviral treatment strategies. Since HBsAg loss can rarely (1%) be achieved with current nucleos(t)ide analogues (NA) options, lifelong treatment is usually required in HBeAg-negative patients. In recent years, guidelines have stated that long-term NA treatments can be discontinued for HBeAg-negative patients without achieving HBsAg loss. There is no general consensus on how discontinuation of NA can be included in the treatment approach. This review aimed to evaluate the current literature regarding the discontinuation of NA treatment in HBeAg-negative patients. Patients with HBeAg-negative CHB who have a higher chance of response after discontinuation of NA therapy can be defined as non-cirrhotic patients who have low HBsAg, HBcrAg, and HBV RNA levels at the discontinuation of treatment and accept close follow-up. The management of relapses that develop after NA discontinuation in patients is also unclear. The agent used in NA treatment itself may also affect the pattern of relapse development. Relapse after NA treatment occurs significantly slower and less frequently with entecavir compared to other regimens, including tenofovir dipivoxil. Prospective studies are needed in order to maintain the chance of HBsAg clearance in case of exacerbation and to treat acute exacerbations that can be fatal in a timely manner. Algorithms to be developed for use after discontinuation of NA treatment will help the clinician manage the patient safely.

Hepatitis B core-related antigen dynamics and risk of subsequent clinical relapses after nucleos(t)ide analog cessation

BACKGROUND/AIMS

Finite nucleos(t)ide analog (NA) therapy has been proposed as an alternative treatment strategy for chronic hepatitis B (CHB), but biomarkers for post-treatment monitoring are limited. We investigated whether measuring hepatitis B core-related antigen (HBcrAg) after NA cessation may stratify the risk of subsequent clinical relapse (CR).

METHODS

This retrospective multicenter analysis enrolled adults with CHB who were prospectively monitored after discontinuing entecavir or tenofovir with negative HBeAg and undetectable HBV DNA at the end of treatment (EOT). Patients with cirrhosis or malignancy were excluded. CR was defined as serum alanine aminotransferase > two times the upper limit of normal with recurrent viremia. We applied time-dependent Cox proportional hazard models to clarify the association between HBcrAg levels and subsequent CR.

RESULTS

The cohort included 203 patients (median age, 49.8 years; 76.8% male; 60.6% entecavir) who had been treated for a median of 36.9 months (interquartile range [IQR], 36.5-40.1). During a median post-treatment follow-up of 31.7 months (IQR, 16.7-67.1), CR occurred in 104 patients with a 5-year cumulative incidence of 54.8% (95% confidence interval [CI], 47.1-62.4%). Time-varying HBcrAg level was a significant risk factor for subsequent CR (adjusted hazard ratio [aHR], 1.53 per log U/mL; 95% CI, 1.12-2.08) with adjustment for EOT HBsAg, EOT anti-HBe, EOT HBcrAg and time-varying HBsAg. During follow-up, HBcrAg <1,000 U/mL predicted a lower risk of CR (aHR, 0.41; 95% CI, 0.21-0.81).

CONCLUSION

Dynamic measurement of HBcrAg after NA cessation is predictive of subsequent CR and may be useful to guide post-treatment monitoring.

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.

Severe hepatitis B flares with hepatic decompensation after withdrawal of nucleos(t)ide analogues: A population-based cohort study

BACKGROUND

Finite nucleos(t)ide analogue (NUC) therapy has been proposed as an alternative treatment strategy for chronic hepatitis B (CHB).

AIM

To quantify the incidence of severe hepatitis flares following NUC cessation in everyday clinical practice.

METHODS

This population-based cohort study enrolled 10,192 patients (male 71.7%, median age 50.9 years, cirrhosis 10.7%) who had received first-line NUCs for at least 1 year before discontinuing treatment. The primary outcome was severe flare with hepatic decompensation. We used competing risk analyses to assess event incidences and associated risk factors.

RESULTS

During a median follow-up of 2.2 years, 132 patients developed severe flares with hepatic decompensation, yielding a 4-year cumulative incidence of 1.8% (95% confidence interval [CI], 1.5%-2.2%). Significant risk factors were cirrhosis (adjusted sub-distributional hazard ratio [aSHR], 2.74; 95% CI, 1.82-4.12), manifestations of portal hypertension (aSHR, 2.46; 95% CI, 1.45-4.18), age (aSHR, 1.21 per 10 years; 95% CI, 1.03-1.42) and male sex (aSHR, 1.58; 95% CI, 1.04-2.38). In patients without cirrhosis or portal hypertension (n = 8863), the 4-year cumulative incidence of severe withdrawal flares stood at 1.3% (95% CI, 1.0%-1.7%). For those patients with available data confirming adherence to the standard stopping rules (n = 1274), the incidence was 1.1% (95% CI, 0.6%-2.0%).

CONCLUSIONS

Severe flares with hepatic decompensation were observed in 1%-2% of patients with CHB after stopping NUC therapy in daily practice. Risk factors included older age, cirrhosis, portal hypertension and male sex. Our findings argue against NUC cessation as part of routine clinical care.

Finite nucleos(t)ide analogue therapy in hepatitis B e antigen-negative chronic hepatitis B: From an "option" to an "active recommendation"

Nucleos(t)ide analogue (Nuc) including entecavir, tenofovir disoproxil fumarate, and tenofovir alafenamide may suppress hepatitis B virus (HBV) DNA profoundly but have no direct action on covalently closed circular DNA, which is a very stable template for HBV production. Therefore, decades of long-term Nuc therapy are required to maintain HBV suppression and to achieve hepatitis B surface antigen (HBsAg) loss in hepatitis B e antigen (HBeAg)-negative patients. However, there are concerns including financial burden, adherence, and willingness for indefinite long-term Nuc therapy. Patients lost to follow-up and hence not monitored may risk severe relapse that may deteriorate to hepatic decompensation or even hepatic failure. Cessation of Nuc therapy in HBeAg-negative patients was initially considered in early 2000s. Earlier findings in Asian patients that finite Nuc therapy over 2-3 years is feasible and safe have founded Asian-Pacific Association for the Study of Liver stopping rule since 2008. Subsequent studies have confirmed the feasibility and safety of the strategy of finite Nuc therapy, which has finally been accepted as "an option" by American and European liver associations since 2016. More recent large studies since 2018 have further confirmed the pivotal finding of greatly increased HBsAg loss rate (~5-year 39%) after stopping Nuc therapy. With the high HBsAg loss rate as the main justification, the paradigm shift from indefinite long-term therapy to finite Nuc therapy in HBeAg-negative patients has been changing from an "option" to an "active recommendation" aiming to achieve HBsAg loss. More studies are needed to fine-tuning the strategy, including research for the optimal duration of consolidation therapy, timing to stop, and to start retreatment.