Virological and immunological predictors of long term outcomes of peginterferon alfa-2a therapy for HBeAg-negative chronic hepatitis B

Background/Purpose: Predictors of long-term outcomes of peginterferon (PegIFN) therapy for patients with chronic hepatitis B (CHB) remain to be explored. This study aimed to evaluate the predictive value of virological and immunological biomarkers and outcomes of PegIFN for CHB. Methods: 57 HBeAg-negative CHB patients receiving 48 weeks of PegIFN therapy were prospectively followed for a median period of 5.3 years after the end of treatment (EOT). Serum CXCL9 and IP-10 levels were measured. Flow cytometry analysis for T cell subsets was performed in 23 patients. Factors associated with long-term outcomes were analyzed. Results: The cumulative incidences of virological relapse, clinical relapse and HBsAg loss at year 7 were 18.1%, 0%, 31.6%, respectively, in patients with sustained off-treatment virological response (SVR), and 100%, 67.4%, 6.7%, respectively, in patients without SVR. By multivariate analysis, baseline CXCL9 > 80 pg/mL (hazard ratio (HR) = 0.418, p = 0.018) and on-treatment HBsAg declines were associated with a lower risk of virological relapse. Non-SVR was the only predictor of clinical relapse. CXCL9 >200 pg/mL (HR = 8.154, p = 0.038) and HBsAg <750 IU/mL (HR = 10.507, p = 0.036) were baseline predictors of HBsAg loss, while HBsAg decline >1 log at EOT (HR = 23.296, p = 0.005) was the on-treatment predictor of HBsAg loss. In subgroup patients with available PBMC, populations of T cell subsets correlated with virological and clinical relapses in univariate analysis. Conclusion: Baseline serum CXCL9 and HBsAg levels could predict HBsAg loss after PegIFN therapy for HBeAg-negative CHB. Combining virological and immunological biomarkers could predict long-term outcomes of PegIFN therapy for HBeAg-negative CHB.