Nucleic Acid Polymer Therapy for Hepatitis B Virus: Strong Hepatitis B Surface Antigen Decline But Many Unanswered Questions

End-of-treatment HBsAg, HBcrAg and HBV RNA predict the risk of off-treatment ALT flares in chronic hepatitis B patients

BACKGROUND/PURPOSE(S)

Since ALT flares after therapy withdrawal are associated with adverse outcomes, risk stratification is of major importance. We aimed to study whether off-treatment flares are related with virological outcomes, and if serum levels of novel biomarkers at end-of-treatment (EOT) can predict flares.

METHODS

Chronic hepatitis B patients who participated in three global randomised trials of peginterferon-based therapy were studied (99-01, PARC, ARES). HBV RNA, HBsAg and HBcrAg were quantified at EOT. Associations between EOT biomarker levels and flares were assessed as continuous data and after categorisation. Flares were defined as ALT ≥5xULN during six months after therapy cessation.

RESULTS

We included 344 patients; 230 HBeAg-positive and 114 HBeAg-negative. Patients were predominantly Caucasian (77.0%) and had genotype A/B/C/D in 23.3/7.3/13.4/52.3%. Flares were observed in 122 patients (35.5%). Flares were associated with lower rates of sustained response (3.5% vs 26.8% among patients with and without a flare; p < 0.001). Higher HBsAg (OR 1.586, 95%CI 1.231-2.043), HBV RNA (OR 1.695, 95%CI 1.371-2.094) and HBcrAg (OR 1.518, 95%CI 1.324-1.740) levels were associated with higher risk of flares (p < 0.001). Combinations of biomarkers further improved risk stratification, especially HBsAg + HBV RNA. Findings were consistent in multivariate analysis adjusted for potential predictors including HBeAg-status and EOT-response (HBV DNA <200 IU/mL).

CONCLUSION

Off-treatment ALT flares were not associated with favourable virological outcomes. Higher EOT serum HBsAg, HBcrAg and HBV RNA were associated with a higher risk of flares after therapy withdrawal. These findings can be used to guide decision-making regarding therapy discontinuation and off-treatment follow-up.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00114361, NCT00146705, NCT00877760.

Cautious optimism in anticipation of hepatitis B curative therapies

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