Off-tenofovir hepatitis flares in HBeAg-negative patients occur earlier, more frequent and severe than those off-entecavir therapies

Incidences of Virological and Clinical Relapses After Cessation of Tenofovir Alafenamide, Tenofovir Disoproxil Fumarate, or Entecavir in Patients With HBeAg-Negative Chronic Hepatitis B

BACKGROUND AND AIM

The relapse pattern following the discontinuation of tenofovir alafenamide (TAF) in patients with chronic hepatitis B (CHB) remains unclear. This study aimed to compare the 2-year incidences of virological and clinical relapses among patients who discontinued TAF versus those who discontinued tenofovir disoproxil fumarate (TDF) or entecavir (ETV).

METHODS

This multicenter retrospective study enrolled noncirrhotic hepatitis B e antigen (HBeAg)-negative CHB patients who discontinued TAF, TDF, or ETV with undetectable HBV DNA at treatment cessation. For patients who switched from ETV or TDF to TAF, a minimum TAF exposure duration of 12 months was required for inclusion in the off-TAF group. Inverse probability of treatment weighting was employed to adjust for baseline differences.

RESULTS

A total of 162 patients (off-TAF: 37, off-TDF: 87, off-ETV: 38) were included in the primary analysis. The 2-year cumulative incidence of virological relapse was significantly higher in the off-TAF group (85.0%) compared to the off-TDF group (69.5%, p = 0.024) and the off-ETV group (51.5%, p = 0.010). Similarly, the 2-year cumulative incidence of clinical relapse was significantly higher in the off-TAF group (62.4%) compared to the off-TDF group (39.0%, p = 0.026) and the off-ETV group (22.5%, p = 0.024). Consistent results were observed in patients meeting the 2012 APASL stopping criteria.

CONCLUSIONS

HBeAg-negative patients who discontinue TAF face a higher risk of both virological and clinical relapses compared to those discontinuing TDF or ETV. These findings underscore the need for more intense monitoring in CHB patients after TAF cessation.

Hepatitis B Surface Antigen Seroclearance Rate After Stopping Nucleos(t)ide Analogues in Chronic Hepatitis B-A Systematic Review and Meta-Analysis

AIM

To identify factors influencing HBsAg seroclearance rates after stopping nucleos(t)ide analogue (NA) therapy in patients with chronic hepatitis B (CHB).

METHODS

We conducted a comprehensive literature search in databases from inception to July 2024. Subgroup analyses and meta-regression were performed to determine factors associated with HBsAg seroclearance, including ethnicity, HBV genotype, NA therapy duration, end-of-treatment (EOT) qHBsAg levels, HBeAg status, cirrhosis status, and follow-up duration.

RESULTS

The meta-analysis included 62 studies (n = 9867) with a pooled HBsAg seroclearance rate of 10% (95%CI: 8%-12%, I2 = 92%) after NA cessation. HBeAg-negative patients showed significantly higher rates than HBeAg-positive patients (11% vs. 5%, p = 0.030). Subgroup analysis revealed higher seroclearance with follow-up of >5 years (18%, p = 0.004), showing significantly higher rates were observed in studies with longer follow-up periods. Caucasians showed a higher rate (12%) than Asians (9%, p = 0.067). Studies adhering to AASLD, EASL, or APASL stopping rules showed no significant differences in rates. Patients with EOT qHBsAg ≤2.0 log IU/mL had higher rates (23%) than those with >2.0 log IU/mL (11%). Re-treated patients had lower seroclearance (6%) compared to those not re-treated (17%, p = 0.178). Meta-regression identified ethnicity, HBeAg status, and follow-up duration as significant contributors to heterogeneity. Egger's test showed no evidence of publication bias (p = 0.1928).

CONCLUSION

Our meta-analysis highlights the role of ethnicity, EOT qHBsAg levels, HBeAg-status, and follow-up duration in determining HBsAg seroclearance rates. These findings stress the need for personalized NA discontinuation strategies and further research on HBV genotypes and biomarkers to improve treatment outcomes and predict seroclearance more accurately.

Predictors of hepatic flares after nucleos(t)ide analogue cessation - Results of a global cohort study (RETRACT-B study)

BACKGROUND & AIMS

Flares after nucleos(t)ide analogue (NA) cessation are common and potentially harmful. Predictors of flares are required for risk stratification and to guide off-treatment follow-up.

METHOD

This multicenter cohort study included virally suppressed patients with chronic hepatitis B (CHB) who were hepatitis B e antigen negative at NA cessation. Hepatic flares were defined based on ALT levels of ≥5x, 10x or 20x the upper limit of normal (ULN). Multivariable Cox regression analyses were performed with censoring at retreatment, HBsAg loss or loss to follow-up. A sub-analysis was performed including HBV DNA levels within the first 12 weeks as a time-dependent covariate.

RESULTS

Of the 1,552 included patients, 350 developed a flare (ALT ≥5x ULN), of whom 70.6% did within the first year. One-year cumulative incidences for ALT flares ≥5x, ≥10x, ≥20x ULN were 18.6%, 10.2% and 3.4%, respectively. Severity of flares decreased over time, but severe flares still occurred after 1 year. Thirteen patients decompensated after a flare, of whom three died. Flares did not seem to be associated with increased rates of HBsAg loss (adjusted hazard ratio [aHR] 1.42, p = 0.28). Multivariable analyses showed that older age (aHR 1.02, p = 0.001), male sex (aHR 1.57, p = 0.003), HBsAg levels at NA withdrawal (100-1,000 IU/ml; aHR 1.99, p <0.001; >1,000 IU/ml; aHR 2.65, p <0.001) and tenofovir disoproxil fumarate vs. entecavir therapy (aHR 2.99, p <0.001) were predictive of flares (≥5x ULN). Early HBV DNA levels >5log10 IU/ml were associated with the highest risk of flares (aHR 2.36, p <0.001).

CONCLUSION

Flares are common after NA withdrawal, especially within the first year and can result in hepatic decompensation and death. Older age, male sex, higher HBsAg levels at end of treatment and tenofovir therapy were associated with a higher risk of flares. Close monitoring and retreatment should be considered if HBV DNA levels exceed 5log10 IU/ml within the first 12 weeks.

IMPACT AND IMPLICATIONS

This is the first large global multi-centered cohort study which provides detailed data about flares after nucleos(t)ide analogue cessation in patients with chronic hepatitis B. Older age, male sex, higher HBsAg levels at end of treatment and tenofovir therapy were associated with a higher risk of flares. These results could guide follow-up after withdrawal, helping clinicians identify high-risk patients and decide when to restart anti-viral therapy, which we recommend if HBV DNA levels exceed 5log10 IU/ml within the first 12 weeks.

CLINICAL TRIAL NUMBER

not applicable.

Why and when could nucleos(t)ide analogues treatment be withdrawn?

Oral antiviral therapy to hepatitis B virus (HBV) with nucleos(t)ide analogues (NUCs) is effective in suppressing the viral load leading to improved clinical outcomes. However, functional cure of HBV, indicated by hepatitis B surface antigen (HBsAg) clearance from the serum, is rare. Although safety and adherence may represent minor issues in long-term treatment with the available NUCs, more efficacious treatments with finite treatment duration for patients with chronic hepatitis B (CHB) are currently undergoing active clinical investigation. Available data suggest that HBsAg loss can be achieved in 10% to 20% of patients after NUC discontinuation, at the cost of about 50% to 80% virological relapse and 40% to 55% retreatment with NUC. With this, NUC treatment in patients with cirrhosis should not be stopped to avoid detrimental risk of hepatic decompensation and death. Viral and immune biomarkers, which may be potentially useful in stratifying the patients at risk of relapse after stopping NUC therapy, are under investigation. In the era of personalized medicine aided by artificial intelligence tools, tight monitoring of viral kinetics and algorithmic modeling appear a promising strategy to assist in individualized decision and conclude the optimal timing of the NUC treatment discontinuation.

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.

Higher end-of-treatment HBsAg levels is associated with later onset but not severe relapse in HBeAg-negative chronic hepatitis B patients stopping antivirals

BACKGROUND

Quantitative hepatitis B surface antigen (qHBsAg) level at end-of-treatment (EOT) predict clinical relapse (CR) after nucleos(t)ide analogues (Nuc) in chronic hepatitis B(CHB) patients. It is unclear if higher EOT qHBsAg leads to earlier onset or more severe off-Nuc CR.

AIM

This large cohort study investigates the association between EOT qHBsAg and CR onset/severity.

METHODS

This study enrolled HBeAg-negative CHB patients who had achieved undetectable HBV DNA for over 1 year after receiving Nuc therapy before discontinuation. The EOT qHBsAg level was categorised into three groups: <100, 100-999, ≥1000 IU/mL. The study assessed the predictability of qHBsAg levels for CR, and analysed and compared the incidence, time to onset and severity of CR among these three groups.

RESULTS

Patients with higher EOT qHBsAg showed a higher incidence of CR (≥1000, 100-999, <100 IU/mL: 73%, 65%, and 38%, p < 0.01) but a later onset of CR (median time to CR: 35, 33 and 27 weeks, p < 0.01). The predictabilities of EOT qHBsAg for CR were greater in patients aged <50-year-old or with genotype C than in those aged ≥50-year-old or with genotype B. There's no correlation between EOT qHBsAg level and ALT folds at CR (Pearson correlation coefficient: r = -0.03, p = 0.35). EOT qHBsAg was neither a predictor for severe hepatitis flare nor a predictor for hepatic decompensation.

CONCLUSIONS

Predictability using EOT qHBsAg levels for CR differed in subgroups of age and genotypes. Higher EOT qHBsAg levels correlate with higher incidence but later onset of CR. No correlation between EOT qHBsAg and relapse severity was observed.

Hepatocellular carcinoma reduced, HBsAg loss increased, and survival improved after finite therapy in hepatitis B patients with cirrhosis

BACKGROUND AND AIMS

Long-term nucleos(t)ide analog (Nuc) treatment can reduce HCC in patients with HBV-related liver cirrhosis (HBV-LC). Earlier small cohort studies showed a comparable 5-year incidence of HCC in HBeAg-negative patients with HBV-LC who stopped and those continued Nuc therapy. This study aimed to validate these findings using a large cohort with 10-year follow-up.

APPROACH AND RESULTS

From 2 centers, 494 HBeAg-negative patients with HBV-LC who stopped (finite group) and 593 who continued (continuous group) Nuc therapy were recruited. HCC, HBsAg loss, liver-related mortality/transplantation, and overall survival rates were compared between 2 groups with 1:1 propensity score matching of sex, treatment history, types of Nuc, age, transaminases, platelet count, and HBsAg levels at end of therapy in finite group or 3-year on-therapy in continuous groups. During a median follow-up of 6.2 (3.4-8.9) years, the annual and 10-year HCC incidence were lower in finite group (1.6 vs. 3.3%/y and 10-y 15.7% vs. 26.8%, respectively; log-rank test, p <0.0001). The finite group showed greater HBsAg decline/year (-0.116 vs. -0.095 log 10 IU/mL, p =0.0026) and 7.6 times higher 10-year incidence of HBsAg loss (22.7% vs. 3%, p <0.0001). Multivariate Cox regression showed finite therapy an independent factor for HBsAg loss (adjusted HR: 11.79) but protective against HCC (adjusted HR: 0.593), liver-related mortality/transplantation (adjusted HR: 0.312), and overall mortality (adjusted HR: 0.382).

CONCLUSIONS

Finite Nuc therapy in HBeAg-negative HBV-LC may reduce HCC incidence, increase HBsAg loss, and improve survival. Greater HBsAg decline/loss may reflect enhanced immunity and contribute to the reduction of hepatic carcinogenesis.

Treatment cessation in HBeAg-negative chronic hepatitis B: clinical response is associated with increase in specific proinflammatory cytokines

Patients with HBeAg-negative chronic hepatitis B may experience an immune response after stopping nucleos(t)ide analogue (NA)therapy, which may potentially trigger HBsAg loss or off-therapy sustained viral control. The immunological mechanisms determining clinical response remain poorly understood. To identify inflammatory signatures associated with defined outcomes, we analysed plasma cytokines and chemokines from 57 HBeAg-negative patients enrolled in the Nuc-Stop Study at baseline and 12 weeks after NA cessation. Clinical response at 12 weeks was classified into four groups: immune control, viral relapse, evolving clinical relapse, and resolving clinical relapse. Twelve weeks after treatment cessation 17 patients (30%) experienced immune control, 19 (33%) viral relapse, 6 (11%) evolving clinical relapse, and 15 (26%) resolving clinical relapse. There was a significant increase in interferon-γ-induced protein 10 (IP-10; p = 0.012) and tumor necrosis factor (TNF; p = 0.032) in patients with evolving clinical relapse. Sparse partial least-squares multivariate analyses (sPLS-DA) showed higher first component values for the clinical relapse group compared to the other groups, separation was driven mainly by IP-10, TNF, IL-9, IFN-γ, MIP-1β, and IL-12. Our results demonstrate that evolving clinical relapse after NA cessation is associated with a systemic increase in the proinflammatory cytokines IP-10 and TNF.Clinical trial registration: ClinicalTrials.gov, Identifier: NCT03681132.

Hepatitis Flares or Hepatic Decompensation after Discontinuation of Tenofovir Disoproxil Fumarate and Entecavir in Non-Cirrhotic Hepatitis B e Antigen-Negative Patients

Hepatic events can occur after discontinuing antiviral therapy. We investigated factors associated with hepatitis flares and hepatic decompensation after discontinuing tenofovir disoproxil fumarate (TDF) and entecavir (ETV). Hepatitis flares within 6 months and hepatic decompensation were compared between non-cirrhotic hepatitis B e antigen-negative patients after discontinuing TDF or ETV by using the Cox proportional hazard model. The cumulative rates of hepatitis flare at 6 months after discontinuing ETV and TDF were 2% and 19%, respectively (p < 0.001). The respective rates of hepatic decompensation at 6 months were 0% and 7% (p = 0.009). Higher alanine aminotransferase (ALT) (AASLD criteria) at the end of treatment (EOT) (HR = 4.93; p = 0.001), an off-therapy dynamic change in HBV DNA (rapid rebound of HBV DNA from the nadir, ≥1 log10 IU/mL per month) (HR = 10.7; p < 0.001), and the discontinuation of TDF (HR = 6.44; p = 0.006) were independently associated with hepatitis flares within 6 months. Older age (HR = 1.06; p < 0.001) and an off-therapy dynamic change in HBV DNA (HR = 3.26; p = 0.028) were independently associated with hepatic decompensation after the discontinuation of antiviral therapy. In summary, we demonstrated several factors associated with hepatitis flares and hepatic decompensation after discontinuing antiviral therapy in non-cirrhotic hepatitis B e antigen-negative patients.

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.

Letter: Safety after cessation of nucleos(t)ide analogue therapy in patients with chronic hepatitis B infection

This article is linked to Hsu et al papers. To view these articles, visit https://doi.org/10.1111/apt.17614 and https://doi.org/10.1111/apt.17681

Editorial: Mitigating the risk of severe hepatitis flare following nucleoside analogue discontinuation-Insights from a real-world study. Authors' reply

This article is linked to Hsu et al papers. To view these articles, visit https://doi.org/10.1111/apt.17614 and https://doi.org/10.1111/apt.17630

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.

Global burden of hepatitis B virus: current status, missed opportunities and a call for action

Chronic hepatitis B virus (HBV) infection affects about 296 million people worldwide and is the leading aetiology of cirrhosis and liver cancer globally. Major medical complications also include acute flares and extrahepatic manifestations. In addition, people living with HBV infection also experience stigma. HBV-related cirrhosis resulted in an estimated 331,000 deaths in 2019, and it is estimated that the number of deaths from HBV-related liver cancer in 2019 was 192,000, an increase from 156,000 in 2010. Meanwhile, HBV remains severely underdiagnosed and effective measures that can prevent infection and disease progression are underutilized. Birth dose coverage for HBV vaccines remains low, particularly in low-income countries or regions where HBV burden is high. Patients with HBV infection are inadequately evaluated and linked to care and are undertreated worldwide, even in high-income countries or regions. Despite the goal of the World Health Organization to eliminate viral hepatitis as a public health problem by 2030, the annual global deaths from HBV are projected to increase by 39% from 2015 to 2030 if the status quo remains. In this Review, we discuss the current status and future projections of the global burden of HBV infection. We also discuss gaps in the current care cascade and propose future directions.

Early virologic relapse predicts alanine aminotransferase flares after nucleos(t)ide analogue withdrawal in patients with chronic hepatitis B

When patients with chronic hepatitis B (CHB) stop nucleos(t)ide analogue (NA) therapy before achieving HBsAg loss, flares often ensue which are challenging to predict early. We determined the incidence, severity, outcome and predictors of flares after NA withdrawal. Forty-five patients enrolled in an RCT were included; 107 patients from an external, prospective cohort were used for validation. Retreatment criteria were pre-defined. Pre- and post-treatment predictors of alanine aminotransferase (ALT) flare (>5× ULN) were evaluated by Cox proportional-hazards regression. Seventy-two weeks after NA withdrawal, 23/45 (51%) patients had developed >5× ULN and 14 (31%) >20× ULN. Median time to develop ALT >5× ULN was 12 weeks after NA withdrawal. Independent predictors of ALT >5× ULN were male sex (HR [95% CI] 3.2 [1.2-8.9]; p = 0.03) and serum HBV DNA (1.2 [1.0-1.8]; p = 0.03) at Week 6 off-therapy. Specifically, week 6 HBV DNA >10,000 IU/ml predicted ALT >5× ULN (3.4 [1.4-8.4]; p = 0.01), which was externally validated. In conclusion, this study on post-treatment flares revealed a high cumulative incidence in CHB. Week 6 HBV DNA >10,000 IU/ml independently predicted flares. The proposed threshold enables prediction of imminent flares in patients who may benefit from closer monitoring and earlier retreatment.

A switch from tenofovir to entecavir prior to hepatitis B treatment cessation is associated with a reduced risk of off-therapy relapse: An observational study

BACKGROUND AND AIM

In HBeAg negative chronic hepatitis B (CHB) patients, clinical relapse (CR) occurs more frequently, much earlier and often more severely after stopping tenofovir (TDF) and other nucleos(t)ide analogues (Nucs) than after stopping entecavir (ETV). It is unknown whether off-Nuc hepatitis flare can be alleviated by switching from one Nuc to another.

METHODS

HBeAg-negative CHB patients who had stopped Nuc according to the APASL stopping rule and had been followed-up for > 48 weeks after Nuc cessation were recruited. Patients were classified as four groups: ETV monotherapy (mono-ETV), TDF monotherapy (mono-TDF), switched to ETV (switch-ETV), and switched to TDF (switch-TDF). Both switch groups had switched to the replacement Nuc > 12 weeks prior to end of therapy. Propensity score matching (PSM) was performed to minimize confounders among groups. Cox regression analysis was used to identify risks factors for off-Nuc CR and flares.

RESULTS

A total of 1309 patients (1022 mono-ETV, 219 mono-TDF, 40 switch-ETV and 28 switch-TDF) were enrolled. The median time to CR was 39, 13, 38 and 14 weeks in mono-ETV, mono-TDF, switch-ETV and switch-TDF respectively (P < 0.001). After PSM, the mono-ETV (adjusted HR: 0.39, P < 0.001) and switch-ETV patients (adjusted HR: 0.41, P = 0.003) had both significantly later occurrence and lower rates of CR and flare.

CONCLUSION

In summary, the incidence and timing of CR was determined by ETV or TDF in the last 3 months prior to end of treatment. Patients treated with non-ETV-Nuc switched to ETV > 12 weeks before end of the original Nuc therapy may reduce/defer CR.

Hepatitis B flare: the good, the bad and the ugly

INTRODUCTION

Hepatitis B flare, defined as an event of abrupt ALT elevation to >5x ULN, is a frequent episode during the natural course or during/after antiviral therapy of chronic HBV infection, in both HBeAg-positive and HBeAg-negative patients with chronic hepatitis B or liver cirrhosis.

AREAS COVERED

The definition, pathogenesis, clinical presentation, and management of hepatitis B flares in the published literature were reviewed. Hepatitis B flares have been considered as a result of the robust immune response of the patient to an upsurging HBV/HBV-antigen(s). 'Host-dominating flares,' reflect effective immune response, may resolve with ALT normalization and decline of HBV/ antigen(s). Contradictorily, 'virus-dominating flares,' reflect ineffective immune response, are usually followed by persistent/intermittent hepatitis and may even develop hepatic decompensation/failure.

EXPERT OPINION

Not all hepatitis B flares require antiviral therapy, and close observation with combined HBsAg/ALT kinetics along the ascending ALT during hepatitis flare may differentiate hepatitis flares for an appropriate treatment/retreatment decision. More studies are needed to verify this proposal. Further immunologic studies using multiple samples during hepatitis B flare are important to clarify the precise underlying mechanisms as the basis for further improvement in the management of hepatitis flare.

The Role of Off-Therapy Viral Kinetics in the Timing and Severity of Flares in Hepatitis B e Antigen-Negative Patients

BACKGROUND & AIMS

Hepatitis B flare occurs earlier and is more severe in patients stopping tenofovir (TDF) compared with entecavir (ETV). This study investigated relationship between hepatitis B virus (HBV) kinetics, onset timing, and the severity of flares.

METHODS

Hepatitis B e antigen-negative chronic hepatitis B patients who developed off-ETV or off-TDF hepatitis flare were recruited. Their HBV kinetics and the severity of flares were compared between patients with early (<6 months) and late (between 6 and 24 months) flares. Propensity score matching was performed at 1:1 adjusting for age, sex, cirrhosis, and end-of-treatment (EOT) hepatitis B surface antigen between off-ETV and off-TDF flares.

RESULTS

After propensity score matching, 76% and 15% of each 107 off-TDF and off-ETV patients, respectively, developed early flare. A much steeper HBV DNA upsurge (ΔHBV DNA/month) was observed in off-TDF than off-ETV flares (2.12 vs 0.73 log₁₀ IU/mL; P < .01). Greater ΔHBV DNA/month correlated with earlier timing and higher peak alanine aminotransferase levels of flares. ΔHBV DNA/month ≥2.5 log₁₀ IU/mL was an independent factor for severe off-TDF flare, and ≥1 log₁₀ IU/mL was a predictor for severe off-ETV flares.

CONCLUSIONS

Greater HBV DNA upsurge rate (ΔHBV DNA/month) ≥1 log₁₀ IU/mL is a key factor for an earlier onset and more severe flare. More frequent ΔHBV DNA/month ≥1 log₁₀ IU/mL in off-TDF than off-ETV flares may explain why off-TDF flare mostly occurred early and was more severe. More stringent monitoring in those with ΔHBV DNA/month ≥1 log₁₀ IU/mL at flare, especially ≥2.5 log₁₀ IU/mL in early off-TDF flares, is important for timely retreatment to prevent decompensation.

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.