Three vs Four Dose Schedule of Double Strength Recombinant Hepatitis-B Vaccine in HIV-infected Children: A Randomized Controlled Trial.

Objective: To compare seroprotection rates and the anti-HBs titers following primary immunization with double strength (20 µg) recombinant hepatitis B virus (rHBV) vaccine administered intramuscularly (IM) in a 3-dose (0, 1 and 6 months) vs 4-dose (0, 1, 2 and 6 months) schedule in HIV-infected children receiving antiretroviral therapy (ART). An accelerated 3-dose schedule (0, 1, 2 months) within the 4-dose group was also compared.

Design: Randomized controlled trial.

Setting: Pediatric ART clinic of a tertiary hospital in Delhi from November, 2017 to April, 2019.

Participants: Fifty (25 per group) HIV-infected children aged 18 months - 12 years receiving ART for at least 6 months who had not received any prior dose of HBV vaccine, and were anti-HBs negative.

Intervention: Group 1 received 20 µg of rHBV vaccine IM (in deltoid muscle) at 0, 1, and 6 months, and group 2 received 20 µg the same vaccine at 0, 1, 2 and 6 months.

Outcome Variables: Anti-HBs titers and proportion of responders in 3-dose vs 4-dose group at seventh and twelfth month and at third month after an accelerated 3-dose schedule.

Results: Median (IQR) anti-HBs titers at the seventh month were significantly higher in group 2 [225.7 (151-300) IU/L] compared to group 1 [138.2 (35.2-250) IU/L], but were comparable at the 12th month. Seroprotection rates were comparable between group 2 and group 1 at 7th month (96% vs 80%; P=0.19) and 12th month (96% vs 88%; P=0.61). The proportion of good responders were also comparable between the groups at 7th month and 12th month (both P=0.29). Accelerated 3-dose schedule achieved comparable anti-HBs titers [179.9 (130.6-250) IU/L] and seroprotection rate (92%) one month after completion of schedule to the standard 3-dose + schedule.

Conclusions: A 3-dose double strength recombinant HBV vaccine schedule offers comparable seroprotection to 4-dose schedule for HIV-infected children receiving ART.