CHA Vaccine Institute, a subsidiary of CHA Biotech, has disclosed the top-line results from the phase 1 clinical trial of its third-generation hepatitis B vaccine candidate, CVI-HBV-002, which showed that the candidate had higher efficacy compared to currently available vaccines. 

The announcement provides insights into the vaccine's safety, reactogenicity, and immunogenicity over a 48-week period, involving 30 adult participants aged between 19 and 65.

The trial, approved by the Ministry of Food and Drug Safety in June 2021, assessed CVI-HBV-002, which includes a novel third-generation recombinant protein antigen, L-HBsAg, and an adjuvant, L-pampo.

According to the company, these components are designed to enhance the vaccine's efficacy as L-HBsAg offers a 200-fold increase in preventive effect compared to the antigens used in current second-generation vaccines, while L-pampo aims to induce both humoral and cellular immune responses.

Results from the immunogenicity assessment indicate that the serum protection rate (SPR) reached 92.86 percent after the first dose and 100 percent following the second and third doses, maintaining 100 percent at the conclusion of the 48-week follow-up period.

This efficacy surpasses the 81.3 percent serum protection rate observed with three doses of previously approved vaccines.

No serious adverse reactions were reported among the participants, affirming the vaccine's safety profile.

Notably, the trial included individuals previously unresponsive to hepatitis B vaccines or without vaccination history but negative for hepatitis B antibodies, all of whom achieved and maintained a 100 percent serum protection rate.

CHA Vaccine Institute aims to further develop CVI-HBV-002 as Korea's first two-dose hepatitis B vaccine, as this approach could offer a viable option for those unresponsive to existing vaccines.

"The clinical trial showed high safety and immunization effectiveness, confirming the potential to overcome the limitations of existing vaccines," CHA Vaccine Institute CEO Yum Jung-sun said. "We will do our best to commercialize the vaccine by starting a global phase 2 clinical trial this year and transferring the technology to China and Eastern Europe."

According to the World Health Organization (WHO), two billion people have been infected with the hepatitis B virus, with about 260 million enduring chronic infections. The U.S. Centers for Disease Control and Prevention (CDC) also recommends hepatitis B vaccinations for all adults aged 19 to 59.