Decoding Hepatitis B: Can We Predict Treatment Success?
"New research identifies patterns in hepatitis B surface antigen levels that may help predict the effectiveness of long-term antiviral therapy, offering hope for more personalized treatment approaches."
Chronic hepatitis B (CHB) is a significant global health challenge, particularly in endemic regions. While nucleos(t)ide analogues (NAs) have revolutionized treatment, effectively suppressing the hepatitis B virus (HBV), the long-term outcomes remain variable. A key goal of therapy is the loss of hepatitis B surface antigen (HBsAg), indicating viral clearance, but this is rarely achieved with NA therapy alone.
The challenge lies in predicting which patients will respond best to long-term NA treatment. Traditional approaches often fall short, highlighting the need for more sophisticated methods to assess treatment efficacy. Researchers have been exploring the potential of monitoring HBsAg levels over time to identify patterns that correlate with treatment success.
This article delves into a recent study that used group-based trajectory models (GBTMs) to analyze HBsAg kinetics in patients receiving long-term NA therapy. By identifying distinct patterns of HBsAg decline, the study aims to provide clinicians with a more accurate tool for predicting treatment outcomes and tailoring therapy to individual patients.
HBsAg Kinetics and Functional Cure
HBsAg loss or seroconversion is considered the ideal endpoint of antiviral therapy and the ultimate treatment goal in chronic hepatitis B. Baseline HBsAg levels are associated with the likelihood of achieving HBsAg loss, which defines a functional cure. However, optimal HBsAg cut-offs for predicting HBsAg loss have not been systematically established, and research has identified a need to analyze HBsAg trends and forecast the time to seroclearance during nucleos(t)ide analogue therapy.
From Seroconversion to Functional Cure
HBsAg seroclearance and HBeAg seroconversion are described as critical immunologic milestones in the natural history and treatment of chronic hepatitis B. HBeAg seroconversion generally reflects the initial establishment of immune-mediated control over viral replication and is considered an important prerequisite for subsequent HBsAg decline. More recent work has focused on HBsAg trajectories during long-term nucleos(t)ide analogue therapy and their association with long-term treatment outcomes, supporting the use of varying HBsAg levels as watersheds for personalized management and clinical-trial screening.
Unlocking Treatment Success: Tracking HBsAg Trajectories
The study enrolled 329 treatment-naive CHB patients, infected with either genotype B or C, who received NA therapy for at least five years. Researchers used GBTMs to identify distinct patterns in their HBsAg levels over time. The findings revealed three distinct groups of patients based on their HBsAg kinetics, both for those who were hepatitis B e antigen (HBeAg)-positive and HBeAg-negative.
- HBeAg-Positive Patients: An HBsAg decline of >30% from baseline at 12 months, combined with an HBsAg level of <100 IU/mL at 12 months, predicted trajectory pattern 1 with high accuracy.
- HBeAg-Negative Patients: A baseline HBsAg level of <1000 IU/mL, along with an HBsAg decline of >50% from baseline at 12 months and an HBsAg level of <200 IU/mL at 12 months, effectively predicted trajectory pattern 1.
New Predictive Biomarkers
Recent research is examining whether HBsAg glycan isomers can predict on-treatment HBsAg decline in patients with low-HBsAg chronic hepatitis B receiving nucleos(t)ide therapy. The glycan isomer may serve as a complementary qualitative marker reflecting the cccDNA-dependent, replication-linked component of antigen production in patients with high HBsAg levels. Other work has evaluated the predictive value of hepatitis B virus pregenomic RNA and HBsAg kinetics in 65 HBeAg-positive children who received at least 96 weeks of nucleos(t)ide analogue therapy.
On-Treatment Versus Off-Treatment Control
Current hepatitis B therapy is effective at achieving on-treatment viral suppression, but the cited review distinguishes this from off-treatment viral suppression. Loss of HBsAg is identified as the best surrogate marker of off-treatment viral suppression. This distinction helps explain why treatment success cannot be judged solely by suppression achieved while therapy continues.
A New Era of Personalized Hepatitis B Treatment?
This study offers a promising step toward personalized management of chronic hepatitis B. By using GBTMs to analyze HBsAg kinetics, clinicians may be able to identify patients who are most likely to benefit from long-term NA therapy and tailor their treatment strategies accordingly.
Toward Novel Therapies
A 2025 horizon-scanning review describes chronic hepatitis B as a major global public health challenge affecting over 254 million individuals, with substantial mortality linked to the limited curative potential of current therapies. It surveys emerging trends and future directions in the development of novel anti-hepatitis B virus therapeutics. One highlighted study evaluated the nucleic acid polymer REP 2139 in treatment-naive participants who were HBeAg-negative, anti-HDAg-positive, HDV RNA-positive, had serum HBsAg concentrations exceeding 1000 IU/mL, and had a body mass index above 16 kg/m2.
The ability to predict treatment outcomes early on could help avoid unnecessary long-term treatment for patients who are unlikely to achieve HBsAg loss. This could reduce the risk of drug resistance, minimize side effects, and lower healthcare costs. It also allows for exploring alternative treatment options, such as combination therapies or immunomodulatory agents, for those predicted to have a less favorable response.
While these findings are encouraging, further research is needed to validate these results in larger, more diverse populations and to explore the long-term clinical implications of trajectory-based treatment strategies. However, this study provides a valuable framework for future research and may ultimately lead to improved outcomes for patients with chronic hepatitis B.