Histological response to combination therapy with nucleos(t)ide analogs and peginterferon alpha in treatment-naïve chronic hepatitis B patients.

Although nucleos(t)ide analog (NA) monotherapy is effective in hepatitis B virus suppression and fibrosis regression, serological response rates are not satisfactory. Studies assessing the benefits of combination therapy with NAs and peginterferon alpha (PegIFN alpha) in patients with chronic hepatitis B (CHB) have produced conflicting results and mainly focused on serological outcomes. Histological changes in response to combination therapy have not been evaluated in real-world practice. This study aimed to evaluate the histological changes in response to NA-PegIFN alpha combination therapy in CHB patients and to comprehensively compare the efficacy of NA-PegIFN alpha combination therapy and NA monotherapy. We conducted a retrospective analysis of data from 40 CHB patients who underwent either NA-PegIFN alpha combination therapy or NA monotherapy. Changes in histology at 48 weeks after treatment initiation were evaluated. Serological characteristics were also analysed and compared between the NA-PegIFN alpha combination therapy and NA monotherapy groups and between histological responders and nonresponders. Compared to baseline biopsies, both fibrosis staging and necroinflammatory grading scores were significantly lower in the second biopsies examined post-treatment in both groups. Nearly all patients experienced a reduction in inflammation (87.5% in both groups), but there was a subgroup of patients who exhibited either no significant improvement or fibrosis progression (33.3% and 31.2% in the NA monotherapy and NA-PegIFN alpha combination therapy groups, respectively). Nearly, all patients achieved ALT normalization and sustained virological response (SVR) after 48 weeks of antiviral treatment. Approximately one-third of individuals (36.8% and 30% in the two groups, respectively) achieved HBeAg loss at 48 weeks after treatment initiation. Although there were no significant differences in overall rates of histological, biochemical, virological and serological responses between the two groups, an earlier virological response and a higher cumulative SVR rate over time were observed during long-term follow-up in patients treated with NA-PegIFN alpha combination therapy (P = 0.0129). Trends of more rapid HBeAg loss and a higher cumulative HBeAg loss rate throughout long-term follow-up were also observed but were not statistically significant. The ALT normalization rates at 24 and 48 weeks after treatment initiation were associated with the histological response. Significant regression of fibrosis and resolution of necroinflammation were induced with either NA-PegIFN alpha combination therapy or NA monotherapy. Significant biochemical, virological and serological responses were observed in both groups, and the response rates at 48 weeks were similar in the two groups. Over time during long-term follow-up, the virological and serological responses were faster and superior following the combination regimen.