Study of TAK-816 in Healthy Infants

Haemophilus Influenzae type b (Hib) is one of the major causes of infectious meningitis in children, and can also cause sepsis, cellulitis, arthritis, epiglottitis, pneumonia and myelitis.

TAK-816 is a conjugated Hib vaccine being tested in healthy infants aged 3-6 months at the time of the first dose.

The objective of this study is to evaluate the efficacy (immunogenicity) and safety of TAK-816 (10 ϻg/0.5 mL) in comparison with ActHIB (Haemophilus b Conjugate Vaccine) as a control.

In addition, the efficacy (immunogenicity) and safety of Absorbed Diphtheria-Purified Pertussis-Tetanus Combined (DPT-TAKEDA) vaccine when TAK-816 and DPT vaccine are administered concomitantly will also be investigated.

For the Primary Immunization Phase of this study: three doses of TAK-816 or ActHIB 10 µg/0.5 mL and DPT-TAKEDA 0.5 mL will be administered at 4-week intervals over 8 weeks (Visit 1, 2, 3). At4 weeks after the third dose, a follow-up observation and evaluation will be made (Visit 4).

For the Booster Vaccination Phase of this study: a single dose of TAK-816 or ActHIB 10 µg/0.5 mL and DPT-TAKEDA 0.5 mL will be given at 52 weeks after the third dose (Visit 5). At 4 weeks after the fourth dose, a follow-up observation and evaluation will be made (Visit 6).

Inclusion criteria

• Male or female infants aged ≥3 and <7 months (excluding hospitalized infants).
• Infants whose legal acceptable representatives have given informed consent to the study prior to enrollment.
• Infants whose parents or legal guardians have agreed to cooperate with the investigator during the study period.

Exclusion criteria

• Any serious acute illness.
• Any underlying cardiovascular, renal, hepatic, or hematologic disease, and/or developmental disorder.
• History of possible Haemophilus influenzae type b (Hib) infection.
• History of possible pertussis, diphtheria or tetanus infection.
• Previously diagnosed immunodeficiency.
• A documented history of anaphylaxis to any ingredient of the investigational products (TAK-816, ActHIB or DPT-TAKEDA).
• A history of convulsions.
• Previous administration of another Hib vaccine.
• Previous administration of any other vaccine containing any of the components of polio, diphtheria, pertussis, or tetanus.
• Treatment with any live vaccine during the 27 days before the first dose of TAK-816 or with any inactivated vaccine during the 6 days before dosing.