Exploratory Clinical Study of MT-2301

Inclusion criteria

• Healthy infants aged ≥2 and <7 months at the first vaccination of the study drug
• Written informed consent is obtained from a legal guardian (parent)

Exclusion criteria

• With obvious pyrexia (axillary temperature of 37.5ºC or higher) at vaccination of the study drug
• With known serious acute disease
• With known underlying disease such as cardiovascular disease, renal disease, hepatic disease, blood dyscrasia, and respiratory disease
• With past diagnosis of immunodeficiency or currently under immunosuppressive treatment
• History of anaphylaxis due to food or pharmaceuticals
• With experience of Hib infection, diphtheria, pertussis, tetanus, and acute poliomyelitis
• With experience of Hib vaccination, or administration of vaccine including either diphtheria, pertussis, tetanus, or polio as a constituent
• History of convulsions
• Administered a live vaccine within 27 days before the first vaccination of the study drug, or inactivated vaccine or toxoid within 6 days before vaccination
• Administered transfusion, immunosuppressant (excluding drugs for external use), or immunoglobulin formulation
• Administered corticosteroid 2 mg/kg per day or more as prednisolone (excluding drugs for external use) continuously for more than 1 week
• Participated in other studies within 12 weeks before obtaining consent