Assessment of the immunogenicity and reactogenicity of a quadrivalent diphtheria, tetanus, acellular pertussis and hepatitis B (DTPa-HBV) vaccine administered in a single injection with Haemophilus influenzae type b conjugate vaccine, to infants at 2, 4 and 6 months of age

This double-blind, randomised study was performed to assess the immunogenicity and reactogenicity of three lots of a quadrivalent diphtheria-tetanus-acellular pertussis-hepatitis B vaccine (DTPa-HBV) co-administered with three lots of Haemophilus influenzae type b conjugate (Hib) vaccine in one injection, as a primary vaccination course in healthy infants at 2, 4 and 6 months of age. 269 infants (8-11 weeks of age) were randomly allocated to three groups to receive DTPa-HBV/Hib vaccines, concomitantly with oral polio vaccine. Blood samples for antibody determinations were taken before vaccination and 1 month after the third dose in 262 subjects. Local and general symptoms were recorded by parents on diary cards. All vaccinees had post-vaccination protective anti-D and anti-T (greater than or equal to 0.1 IU ml(-1)) antibodies, and 98% had protective anti-HBs antibody titres (greater than or equal to 10 mIU ml(-1)). There were no statistically significant differences between groups in post-vaccination anti-D, anti-T, anti-HBs antibody geometric mean titres (GMT), these being 3.49 IU ml(-1), 5.92 IU ml(-1) and 1109 mIU ml(-1), respectively. All subjects responded to three pertussis components, i.e. pertussis toxin (PT), filamentous haemagglutinin (FHA) and pertactin (PRN). Although statistically significant differences in GMTs of anti-PT, anti-FHA and anti-PRN were found between groups, these were not believed to be of any clinical relevance as the minimum GMTs were 60, 193 and 230 EL.U ml(-1) for anti-PT, anti-FHA and anti-PRN, respectively. There were no statistically significant differences in anti-PRP antibody GMT (4.05 mu g ml(-1)) between groups, 100% and 85% of subjects having titres greater than or equal to 0.15 and 1.0 mu g ml(-1), respectively. No symptoms were reported for one third of the subjects. Fever (> 38 degrees C) was reported after 16% of doses, with < 1% having < 39.5 degrees C. Almost all local and general symptoms were mild or moderate, and lasted less than 48 h. No subject dropped out due to a severe adverse reaction. The administration of an experimental mix of DTPa-HBV and Hib vaccines in a single injection is safe, well-tolerated and immunogenic for all vaccine components. (C) 1998 Elsevier Science Ltd. All rights reserved.