a study of dtap//prp-t combined vaccine (actacel) versus local dtap and act-hib monovalent vaccine in healthy infants

Conditions: Diphtheria; Tetanus; Pertussis; Haemophilus Influenzae Type B

Summary: the purpose of this study is to assess the immunogenicity and safety of actacel combined vaccine in support of registration of this product in china primary objectives: * to demonstrate that actacel vaccine administered at 2, 3 and 4 months of age or at 3, 4 and 5 months of age is not inferior, in terms of seroprotection, to wuhan's diphtheria, tetanus, acellular pertussis (dtap) and haemophilus influenzae type b (act-hib) vaccine given concomitantly, for diphtheria, tetanus, and polyribosyl ribitol phosphate (prp) antigens, one month after the three-dose primary vaccination. * to demonstrate the superiority, in terms of seroconversion, of actacel vaccine administered at 2, 3 and 4 months of age or at 3, 4 and 5 months of age for pertussis toxoid (pt), fimbriae types 2 and 3 (fim2) and (fim3) pertussis antigens, compared with wuhan's dtap and act-hib vaccines given concomitantly, one month after the three-dose primary vaccination. secondary objectives: * to describe the safety after administration of the study vaccines. * to describe in each group the immunogenicity of the study vaccines one month after the primary vaccination and before and one month after the booster vaccination.

participants will receive a primary vaccination consisting of three doses of actacel at either 2, 3, and 4 months of age or at 3, 4, and 5 months of age; or wuhan dtap and act-hib vaccines at 3, 4, and 5 months of age. all participants will receive a single booster dose at 18-20 months of age and will be followed up for one month after the last dose of study vaccine.

Eligibility criteria:
inclusion criteria : * aged 2 months on the day of inclusion * born at full term pregnancy (≥ 36 weeks) with a birth weight ≥ 2.5 kg * informed consent form signed by the parent(s) or legal representative * participant and parent/legal representative able to attend all scheduled visits and to comply with all trial procedures exclusion criteria : * participation in another clinical trial investigating a vaccine, drug, medical device, or a medical procedure in the 4 weeks preceding the first trial vaccination * planned participation in another clinical trial during the present trial period * known or suspected congenital or acquired immunodeficiency, immunosuppressive therapy such as anti-cancer chemotherapy or radiation therapy since birth, or long-term systemic corticosteroids therapy * known systemic hypersensitivity to any of the vaccine components or history of a life-threatening reaction to the trial vaccine or to a vaccine containing any of the same substances * chronic illness at a stage that could interfere with trial conduct or completion, in the opinion of the investigator * receipt of blood or blood-derived products since birth that might interfere with the assessment of immune response * receipt or planned receipt of any vaccine in the 4 weeks preceding or following any trial vaccination (except oral poliovirus (opv), bacillus calmette-guérin (bcg), and hepatitis b vaccines which cannot be given within 8 days before or after any study vaccination) * history of seizures * known personal or maternal human immunodeficiency virus (hiv), hepatitis b (hb) surface antigen or hepatitis c seropositivity * history of diphtheria, tetanus, pertussis or haemophilus influenzae type b infection (confirmed either clinically, serologically or microbiologically) * previous vaccination against diphtheria, tetanus, pertussis or haemophilus influenzae type b disease with either the trial vaccine or another vaccine * participant at high risk for diphtheria, tetanus, pertussis or haemophilus influenzae type b infection during the trial * thrombocytopenia, bleeding disorder or anticoagulants in the 3 weeks preceding inclusion contraindicating intramuscular vaccination * history of contraindication to vaccination with pertussis-containing vaccine * febrile illness (axillary temperature ≥37.1°c) or moderate or severe acute illness/infection on the day of inclusion, according to investigator judgment temporary contraindications that must be resolved before vaccination: * acute febrile illness within the 72 hours preceding the vaccination, or temperature ≥37.1°c present at this visit * any vaccination in the 4 weeks preceding the vaccination (except opv, bcg, and hepatitis b vaccines which cannot be given within 8 days before or after any study vaccination) * systemic corticosteroids therapy (prednisone or equivalent) for more than 2 consecutive weeks within the past 3 months

Keywords: diphtheria tetanus pertussis haemophilus influenzae type b