Indian Pediatrics - Editorial

Editorial

Indian Pediatrics 2008; 45:815-816

Immunogenicity and Safety of DTPw-Hepatitis B Combined Vaccines

Om Singh

Senior Scientist and Head, Immuno-endocrinology Laboratory, National Institute of Immunology,
New Delhi 110 067, India. E-mail: [email protected]

Hepatitis B virus infection is one of the major global health problems despite the availability of prophylactic vaccines. The WHO-Expanded Program on Immunization (WHO-EPI) recommends immunization of all infants against hepatitis B. The best way to achieve this goal of universal vaccination is by employing vaccine formulations combining the hepatitis B vaccine with the diphtheria, tetanus and whole-cell pertussis (DTPw) vaccine. The immunization schedule and adjuvant (aluminium salt) used in individual vaccine formulations are compatible. Studies have shown that hepatitis B component in the combined vaccine does not impair the immune responses to the other three components of the tetravalent vaccine, and the safety profile of the combined vaccine has been reported to be similar to that of the classical DTPw vaccine(1).

TABLE I

Comparative Immunogenicity of DTPw-Hepatitis B Combined Vaccines

Study	Anti-HBs GMT (mIU/mL)	Anti-diphtheria GMT (IU/mL)	Anti-tetanus GMT (IU/mL)	Anti-pertussis GMT (EIU/mL)
Diez-Delgado,	2318	3.59	5.76	189.3
et al. (1)	(1588-3384)*	(2.76-4.69)	(4.64-7.14)	(159.3-225.1)
Aristegui,	1526	2.10	4.98	134
et al. (3)	(1273-1830)	(1.85-2.39)	(4.40-5.64)	(122-147)
Papaevangelou,	1175	3.69	8.26	61
et al. (4)	(634-2178	(2.62-5.19)	(5.99-11.38)	(47-79)
Shah, et al.(2)	473	1.6	2.1	33.3
ShantetraTM	(10-7036)	(0.1-3.8)	(0.4-9.2)	(21-417)
Shah, et al. (2)	266	1.5	1.9	39
Tritanrix HBTM	(10-1925)	(0.1-4.0)	0.4-5.1)	(22-476)

Integration of the combined vaccine into the routine immunization program should be a positive step towards protecting infants against hepatitis B virus. In this issue of the journal, Shah and colleagues(2) have compared the immunogenicity and safety of an indigenous DTPw-Hepatitis B combined vaccine (ShantetraTM) with the Tritanrix HBTM vaccine in healthy Indian infants. They conclude that the present study has effectively demonstrated the safety and immunogenicity of Shantetra vaccine. Many clinical studies have shown the excellent immunogenicity of each component(1,3,4). However, the GMT antibody titers reported by Shah, et al.(2) are well below the previously published limits (see Table I for comparison), raising some concern. While upper confidence intervals compare well with the reported values, lower confidence interval for HBs and DT titers is the minimum threshold for protection against these diseases, and is at least 50-fold lower than the values reported by others. Even for TT, it is 10-fold lower. The result of this study should encourage further trials to answer this important question: Are some Indian infants poor responders to the combined vaccines?

Funding: None.
Competing interests: None stated.

References

1. Diez-Delgado J, Dal-Ré R, Llorente M, González A, López J. Hepatitis B component does not interfere with the immune response to diphtheria, tetanus and whole-cell Bordetella pertussis components of a quadrivalent (DTPw-HB) vaccine: a controlled trial in healthy infants. Vaccine1997; 15: 1418-1422.

2. Shah R, Raghu MB, Shivanada A, Mangayarkarasi S, Rao I, Rao R, et al. Immunogenicity and safety of an indigenously developed DTPw-Hepatitis B combination vaccine in Indian infants. Indian Pediatr 2008; 45: 819-823.

3. Aristegui J, Garrote E, Gonzalez A, Arrate JP, Perez A, Vandepapeliere P. Immune response to a combined hepatitis B, diphtheria, tetanus and whole-cell pertussis vaccine administered to infants at 2, 4 and 6 months of age. Vaccine 1997; 15: 7-9.

4. Papaevangelou G, Karvelis E, Alexiou D, Kiossoglou K, Roumeliotou A, Safary A, et al. Evaluation of a combined tetravalent diphtheria, tetanus, whole-cell pertussis and hepatitis B candidate vaccine administered to healthy infants according to a three-dose vaccination schedule. Vaccine. 1995; 13: 175-178.