Global 
Deutschland Liver and Bile
Hepatology. 2025;81(1):254-268
Neutralizing antibodies to interferon-α arising during peginterferon therapy of chronic hepatitis B in children and adults: Results from the HBRN trials
Background and aims: Pegylated interferon-α (PegIFNα) is of limited utility during immunotolerant or immune active phases of chronic hepatitis B infection but is being explored as part of new cure regimens. Low/absent levels of IFNα found in some patients receiving treatment are associated with limited/no virological responses. The study aimed to determine if sera from participants inhibit IFNα activity and/or contain therapy-induced anti-IFNα antibodies.
Approach and results: Pre-treatment, on-treatment, and post-treatment sera from 61 immunotolerant trial participants on PegIFNα/entecavir therapy and 88 immune active trial participants on PegIFNα/tenofovir therapy were screened for anti-IFNα antibodies by indirect ELISA. The neutralization capacity of antibodies was measured by preincubation of sera ± recombinant human IFNα added to Huh7 cells with the measurement of interferon-stimulated gene (ISG)-induction by qPCR. Correlations between serum-induced ISG inhibition, presence, and titer of anti-IFNα antibodies and virological responses were evaluated. Preincubation of on-treatment serum from 26 immunotolerant (43%) and 13 immune active (15%) participants with recombinant-human IFNα markedly blunted ISG-induction in Huh7 cells. The degree of ISG inhibition correlated with IFNα antibody titer (p < 0.0001; r = 0.87). On-treatment development of anti-IFNα neutralizing antibodies (nAbs) was associated with reduced quantitative HBsAg and qHBeAg declines (p < 0.05) and inhibited IFNα bioactivity to 240 weeks after PegIFNα cessation. Children developed anti-IFNα nAbs more frequently than adults (p = 0.004) but nAbs in children had less impact on virological responses.
Conclusions: The development of anti-interferon-α (anti-IFNα) neutralizing antibodies during pegylated IFNα treatment diminishes responses to antiviral therapy. Understanding how and why anti-IFNα antibodies develop may allow for the optimization of interferon-based therapy, which is critical given its renewed use in hepatitis B virus-cure strategies.