title: Comparative efficacy of two dosages of recombinant hepatitis B vaccine in healthy adolescents in India.
abstract: BACKGROUND
  Inclusion of hepatitis B vaccine in the Universal Programme of Immunization of all Asian and African countries is hampered by the economic burden on the health budget because of the cost of hepatitis B vaccines. Here we evaluated the immunogenicity, safety, efficacy, and the persistence of antibody to hepatitis B surface antigen (anti-HBs) titers of a new and a low cost recombinant hepatitis B vaccine GeneVac B, with 2 different dosages in healthy adolescents in India.
  
  
  METHODS
  GeneVac-B, a recombinant hepatitis B vaccine (Serum Institute of India, Pune, India), was administered in 10 or 20 microg dose intramuscularly to 2 groups of 100 healthy school-going adolescents at 0-, 1-, and 6-month intervals, who were followed up for 1 year. Group I received 20 mug doses whereas Group II received 10 mug doses. Blood samples were collected 1 month after each dose and 1 year after the third dose. The anti-HBs titers were assayed using commercially available kits to assess the immunogenicity of the 2 dosage schedules. Safety studies were also carried out.
  
  
  RESULTS
  The geometric mean titer value of the anti-HBs titer 1 month after the third dose was 2629 (mlU/mL) in Group I and 1373 mlU/mL for Group II subjects. One year after the third dose, the persistence of anti-HBs in those who had received 20 mug was 2262 mlU/mL whereas it was 1039 mlU/mL in the group receiving 10 microg doses. All the subjects in both the groups were seroprotected at 1 year after vaccination. None of the vaccinees exhibited serious adverse reactions throughout the study period.
  
  
  CONCLUSIONS
  The study demonstrated the immunogenicity of the recombinant hepatitis B vaccine, and confirms that the 0.5 mL (10 microg) dose of GeneVac B can be administered with satisfactory safety and immunogenicity to adolescents up to 19 years of age, reducing the cost to less than U.S. $1.00 per dose making it acceptable for the Universal Programme of Immunization of developing and under developed countries.
authors.affiliation: Department of Microbiology, Dr ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani, Chennai, India.
authors.forename: Vijayakumar
authors.initials: V
authors.lastname: Velu
authors.forename: Subhadra
authors.initials: S
authors.lastname: Nandakumar
authors.forename: Saravanan
authors.initials: S
authors.lastname: Shanmugam
authors.forename: Esaki Muthu
authors.initials: EM
authors.lastname: Shankar
authors.forename: Sundararajan
authors.initials: S
authors.lastname: Thangavel
authors.forename: Prasad Suryakant
authors.initials: PS
authors.lastname: Kulkarni
authors.forename: Sadras Panchatcharam
authors.initials: SP
authors.lastname: Thyagarajan
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D006509:Hepatitis B / Q000517:prevention & control*; D006510:Hepatitis B Antibodies / Q000097:blood; D006514:Hepatitis B Surface Antigens / Q000276:immunology; D017325:Hepatitis B Vaccines / Q000008:administration & dosage / Q000009:adverse effects / Q000191:economics / Q000627:therapeutic use; D006515:Hepatitis B virus / Q000276:immunology*; D006801:Humans; D007194:India; D008297:Male; D016896:Treatment Outcome; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D014614:Vaccines, Synthetic