Chabakshin Research Institute Successfully Completes Phase 1 Clinical Trial for Hepatitis B Vaccine Development

ChabioTech affiliate Chavaccine Research Institute announced on the 31st that it had disclosed the top-line (key indicator) results of the clinical phase 1 study report (CSR) for ‘CVI-HBV-002,’ a third-generation hepatitis B preventive vaccine under development, on the 30th.

Chabacsin Research Institute CI [Photo by Chabacsin Research Institute]

CVI-HBV-002 is a vaccine developed independently by Chavaccine Research Institute that includes the third-generation recombinant protein antigen 'L-HBsAg' and the immune adjuvant 'L-Pampo.' L-HBsAg is a third-generation antigen with 200 times higher preventive efficacy than the second-generation antigen currently used in vaccines, and L-Pampo induces both humoral and cellular immune responses simultaneously, making it more effective than other adjuvants that only induce humoral immune responses.

Hepatitis B is considered one of the most common viral liver diseases. The World Health Organization (WHO) reports that 2 billion people worldwide, roughly one in three, have been infected with the hepatitis B virus, and approximately 260 million people are chronic carriers of the virus. The U.S. Centers for Disease Control and Prevention (CDC) announced a policy in April 2022 recommending hepatitis B vaccination for all adults aged 19 to 59, reflecting a growing market for adult hepatitis B vaccines.

Chavaccine Research Institute received approval from the Ministry of Food and Drug Safety in June 2021 for this phase 1 clinical trial plan and completed administration of CVI-HBV-002 to 30 adults aged 19 to 64 in November 2022. Safety, reactogenicity, and immunogenicity have been evaluated during a 48-week follow-up period. The primary efficacy endpoint was set as the 'seroprotection rate,' defined as the proportion of subjects with an anti-hepatitis B virus titer of 10 mIU/mL or higher.

Clinical trial results showed that the seroprotection rate among the final 29 subjects was 92.86% after the first dose, with 29 out of 30 subjects meeting the criterion. After the second and third doses and the 48-week long-term follow-up, all subjects exhibited anti-hepatitis B virus titers above the threshold, resulting in a 100% seroprotection rate. The company explained that this is superior to the 81.3% seroprotection rate observed after three doses of existing approved vaccines. Safety was also confirmed, as no serious adverse reactions were reported among all subjects.

Since CVI-HBV-002 achieved a 100% seroprotection rate with just two doses and rapidly induced antibody formation, Chavaccine Research Institute plans to develop it as the first two-dose hepatitis B preventive vaccine in Korea. Reducing the number of vaccine doses is expected to improve vaccination accessibility and contribute to national health improvement. It is also anticipated to be a vaccine for those who did not respond effectively to existing vaccines. The clinical trial included non-responders who had previously received hepatitis B vaccines but did not develop antibodies, as well as individuals without a history of hepatitis B vaccination who tested negative for hepatitis B antibodies during screening; all participants reached a 100% seroprotection rate.

Yeom Jeong-seon, CEO of Chavaccine Research Institute, said, “This clinical trial confirmed not only safety but also high immune efficacy, demonstrating the potential to overcome the limitations of existing vaccines. We will do our best to commercialize the vaccine by starting global phase 2 clinical trials within this year and licensing the technology to countries such as China and Eastern Europe.”