COMPARATIVE study of TWO recombinant hepatitis B vaccines (Euvax B and Engerix B) and their interchangeability in infants as a primary vaccination at 0, 1 and 6 months of age

Tregnaghi M¹, Ussher J¹, Baudagna AM¹, Calvari M¹, Grana G¹, Ortiz E²

¹ Centro de Desarollo de Proyectos Avanzados, Hospital Infantil Municipal de Córdoba, Córdoba, Argentina

² Aventis Pasteur, Lyon, France

Objective: This study aimed to demonstrate the equivalence and interchangeability of two WHO approved and recommended yeast-derived recombinant hepatitis B vaccines, Euvax B (marketed as Hepativax in Argentina) vs. Engerix B.

Methods: 300 infants were randomly allocated to three study groups to receive a 3-dose primary vaccination (at 0, 1 and 6 months of age):

group A = 3 doses of Euvax B (Lucky Goldstart Chem. Ltd, 10 μg dose), group B = 3 doses of Engerix B (GlaxoSmithKline, 10 μg dose), and group C = 1 dose of Engerix B followed by 2 doses of Euvax B.

Reactogenicity was from parental reports, reviewed by study medical personnel. Blood sampling before dose 1 and after doses 2 and 3 to assay anti-hepatitis B surface antigen (anti-HBs) by enzyme immunoassay.

Results: All 3 groups experienced equal and very low reactogenicity rates. After the third dose, 100% of infants in each group achieved seroprotective titres (anti-HBs ³ 10 mIU/mL). Geometric mean concentrations were 2334, 1696 and 2105 mIU/mL in groups A, B and C, respectively. Five months after dose 2, seroprotection rates were 95.8%, 94.6% and 90% in groups A, B and C respectively. Statistically, responses to Euvax B, in groups A and C were identical (non-inferior) to Engerix B (group B) in terms of seroprotection rate after the third dose.

Conclusion: Euvax B vaccine, given as a full series or as subsequent doses, is equally immunogenic and safe as Engerix B for primary vaccination in infants. The first two doses gave an early and significant immune response in each group.

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