A finite duration of 900 µg εPA-44 improved Hepatitis B e Antigen (HBeAg) seroconversion in people with HBeAg-positive progressive chronic hepatitis B.

A two-stage phase II randomized clinical trial explored the safety and efficacy of subcutaneous injections of εPA-44 to manage chronic hepatitis B.

This study consisted of (i) Stage I: A 76-week, randomized trial in which 360 human leukocyte antigen A2 (HLA-A2)-positive and HBeAg-positive volunteers were randomized to get 6 injections of nanoparticle vaccine (600 µg or 900 µg) or placebo at weeks 0, four, eight, twelve, twenty, and twenty-eight, and (ii) Stage II: A 68-week open-label extension in which 183 volunteers were given an extended 900 µg εPA-44, and 26 volunteers were monitored for relapse without further therapy. The proportion of people with HBeAg seroconversion at week 76 was the major endpoint ascertained.

At week 76, volunteers receiving 900 µg εPA-44 attained considerably increased HBeAg seroconversion rate versus placebo (38.8% vs. 20.2%). Utilizing the combined outcome of HBeAg seroconversion, alanine aminotransferase normalization and hepatitis B virus DNA < 2,000 IU/mL, both 600 µg (14.3%) and 900 µg (18.1%) led to a substantially increased rate when compared to placebo (5%) at week 76. None of 900 µg vaccine-treated volunteers reported serologic relapse in stage II. The safety profile of nanoparticle therapeutic vaccine was comparable to placebo.

In HLA-A2-positive people having chronic hepatitis B, εPA-44 (de novo designed liposome-based nanoparticle lipopeptide vaccine) monotherapy led to a considerably greater HBeAg seroconversion rate vs. placebo and sustained off-therapeutic effect.