RESUMEN
BACKGROUND: A manufacturing process using a modified adjuvant was developed to optimize the consistency and immunogenicity for recombinant hepatitis B vaccine (control: RECOMBIVAX-HB™). This modified process hepatitis B vaccine (mpHBV), which was previously shown to have an acceptable safety and immunogenicity profile in young adults, has now been studied in newborn infants. METHODS: Healthy 1-10-day-old neonates (N=566) received 3 intramuscular doses (5µg hepatitis B surface antigen [HBsAg] per dose) of either mpHBV or control at Day 1, and Months 1 and 6. Serum antibody to HBsAg (anti-HBs) was assayed at Month 7 (1 month Postdose 3). Anti-HBs geometric mean titers (GMTs) and seroprotection rates (SPRs) (% of subjects with an anti-HBs titer ≥10mIU/mL) were compared at Month 7. After each dose, injection-site adverse experiences (AEs) and axillary temperatures were recorded for 5 days; systemic AEs were recorded for Days 1-14. RESULTS: Month 7 SPR was 97.9% for the mpHBV group and 98.9% for the control. The GMT was 843.7mIU/mL for the mpHBV group and 670.1mIU/mL for the control. The GMT ratio (mpHBV/control) was 1.26 (95% confidence interval [CI]: 0.94, 1.69), meeting the prespecified non-inferiority criteria. The percentages of subjects reporting any AE, injection-site AEs, or systemic AEs were similar across the 2 vaccination groups. There were no serious AEs. CONCLUSIONS: The safety profile of mpHBV was comparable to that of the control vaccine. The geometric mean antibody titer for mpHBV was higher than control vaccine in this infant population, but the difference did not meet the predefined statistical criterion for superiority.