Background and objective: Unlike the commonly seen off-treatment relapse in patients treated with nucleos(t)ide analogues, a finite course of PEG-IFN provides sustained immune control in HBeAg-negative chronic hepatitis B (CHB)patients. The aim of this study is to investigate whether extended pegylated interferon alfa-2a(PEG-IFN) therapy can improve long-term response in HBeAg-negative patients and identify optimal endpoint for this population.
Methods: In this single-center, prospective, open-labeled study, totally 66 HBeAg-negative treatment-naïve patients with ALT ≥2×ULN and HBV DNA≥2000IU/ml but < 200000IU/ml were enrolled. All patients were randomized into 2 groups, treated with PEG-IFN 180 µg/week for 48 weeks in standard therapy group(N=30) or PEG-IFN 180 µg/week for 60 or 72 weeks in extended therapy group(N=36) and followed for 48 weeks post-treatment. The variance analysis, Wilcoxon test, student's t-test, χ 2, exact probability test and CMH analysis were used in this study.
Results: At end of treatment, 94.4%(N=34) in extended therapy group achieved HBV DNA suppression(HBV DNA< 60 IU/ml) which was significantly higher than standard therapy group (73.3%, N=22 , P< 0.05). When followed up to 24 and 48 weeks post-treatment, the response rates reached 88.9% and 77.8% in extended therapy group, both significantly higher than standard therapy group (63.3% and 53.3%, both P< 0.05).
At 48 weeks post-treatment, 36.1%(N=13) in extended therapy group has cleared HBsAg, which was significantly higher than standard therapy group(13.3%, N=4 , P< 0.05).
At end of treatment, in the patients with HBV DNA < 60IU/ml, the cutoff of HBsAg< 1000IU/ml had a PPV of 92% and a NPV of 48.78% for predicting achieving sustained HBV DNA suppression at 48 weeks post-treatment, and HBsAg>1000IU/ml had a PPV of 35.48% and a NPV of 68.57% for predicting not achieving sustained HBV DNA suppression at 48 weeks post-treatment.
Conclusion: Extended PEG-IFN treatment provides significant higher rates of HBV DNA suppression and HBsAg clearance post-treatment in HBeAg-negative CHB. HBsAg level at end of treatment, predictive of sustained response post-treatment, may be an indicator for stopping treatment. |