Ga Rankuwa

Researchers are investigating the immune response and safety of the Hecolin4 vaccine in healthy children aged 2 to 17 years compared to healthy adults aged 18 to 45 years. The study aims to show that the vaccine works at least as well in children as in adults by measuring the seroresponse rates of anti-HEV IgG antibodies four weeks after three doses given at 0, 1, and 6 months. The study also compares immune responses between HIV positive and HIV negative adults and evaluates safety across different age groups. Participants receive intramuscular injections of 30 1g Hecolin4 vaccine in different dosing schedules depending on their age group and study arm. Adults (18-45 years) receive three doses at 0, 1, and 6 months. Children and adolescents (2-17 years) are divided into groups receiving either three doses at 0, 1, and 6 months, two doses at 0 and 6 months, or placebo injections on the same schedule. The study includes a long-term follow-up with additional blood samples collected up to 24 months after the last dose for immunogenicity assessment. Participants will have six blood samples collected throughout the main study at specified time points before and after vaccinations. Those in the HIV positive group will have additional blood tests to measure CD4 cells and viral load. Safety is monitored closely with observation for immediate reactions after each injection, diaries to record local and systemic side effects for 7 days, and tracking of any adverse events for up to 6 months after the last dose. The total participation duration includes vaccination, monitoring, and follow-up visits over two years for some participants.