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Functional cure, defined as sustained HBsAg loss with off-treatment viral suppression, is the ultimate goal of antiviral therapy for chronic hepatitis B.1 Yet with current standard-of-care nucleos(t)ide analogues (NAs), it remains a rarely achieved outcome.1 However, its clinical relevance is profound: HBsAg clearance is linked to substantially lower risks of cirrhosis and hepatocellular carcinoma, and it allows for safe discontinuation of NA therapy.1 The 2025 EASL guidelines accordingly still include pegylated interferon alfa (PEG-IFN) as an option for therapy in selected patients, given its potential to induce a finite off-treatment response.1 However, in clinical practice, PEG-IFN is infrequently used because of its modest efficacy and substantial side-effect burden relative to NAs. The renewed focus on achieving a functional cure has nonetheless revived interest in interferon-based regimens, not only as an add-on to NAs, but increasingly as part of novel combination strategies with, for example, HBsAg-lowering agents.2–4