Entecavir Plus Pegylated Interferon and Sequential Hepatitis B Virus Vaccination Increases Hepatitis B Surface Antigen Seroclearance: A Randomized Controlled Proof-of-Concept Study

BACKGROUND: Hepatitis B surface antigen (HBsAg) seroclearance is considered a functional cure for patients with chronic hepatitis B, but is rarely achievable with oral nucleos(t)ide analogues alone. We conducted a randomized controlled proof-of-concept trial to evaluate the impact of adding pegylated interferon (peg-IFN) alfa-2a plus sequential or concomitant hepatitis B virus (HBV) vaccination. METHODS: A total of 111 patients who achieved serum HBV DNA <20 IU/mL and quantitative HBsAg <3000 IU/mL with entecavir were randomly assigned (1:1:1) to the E + sVIP group (entecavir + peg-IFN alfa-2a [180 µg every week over 48 weeks] plus sequential HBV vaccination [20 µg of HBsAg on weeks 52, 56, 60, and 76]), the E + cVIP group (entecavir + peg-IFN alfa-2a + concomitant HBV vaccination [weeks 4, 8, 12, and 28]), or the control group (entecavir only). The primary endpoint was HBsAg seroclearance at week 100, and secondary endpoints included safety. RESULTS: No differences in baseline quantitative HBsAg were observed among the groups. The E + sVIP group in the intention-to-treat analysis showed a significantly higher chance of HBsAg seroclearance during week 100 than the control group (16.2% vs 0%; P = .025), but the E + cVIP group (5.4%) failed to reach a significant difference (P = .54). Adverse events were significantly more frequent in the E + sVIP (81.1%) and E + cVIP group (70.3%) than the control group (2.7%) (both P < .0001). However, the frequency of serious adverse events did not differ significantly among the 3 groups (2.7%, 5.4%, and 2.7%, respectively; P = 1.00). CONCLUSIONS: Entecavir plus an additional peg-IFN alfa-2a treatment followed by sequential HBV vaccination under an intensified schedule significantly increases the chance of HBsAg seroclearance compared to entecavir alone. CLINICAL TRIALS REGISTRATION: NCT02097004.