Moreover, even for the licensed CpG 1018-adjuvanted hepatitis B vaccine (41), or in clinical trials using CpG7909 (42–44), and CpG-ODN (K3) (45, 46), no safety data on the utility of TLR9-activating CpG-rich adjuvants was available in children. The gene discussed is TLR9; the disease is hepatitis B virus infection.