Phase III Study of Intramuscular TAK-816 in Healthy Infants

A Phase III, Multicenter, Open-Label Study to Evaluate the Safety and Immunogenicity of Intramuscular TAK-816 in Healthy Infants

The purpose of this study is to evaluate the safety and immunogenicity of intramuscular TAK-816 in healthy Japanese infants.

The vaccine being tested in this study is called TAK-816. TAK-816 was being tested to evaluate its safety and immune response after intramuscular (IM) injection with TAK-816. This study evaluated adverse events and the seroprotection rate and geometric mean titer (GMT) of anti-polyribosylribitol phosphate (PRP)-antibodies in participants who were administered TAK-816 IM.

The study enrolled 31 participants. All participants received 3 doses of TAK-816 IM at 4-week intervals as part of the primary vaccination and 1 booster vaccination 52 weeks after the third dose of the primary vaccination.

This multi-center trial was conducted in Japan. The overall time to participate in this study was 64 weeks. Participants made multiple visits to the clinic including a final visit 4 weeks after last dose of study drug for a follow-up assessment.

Inclusion Criteria:

1. Healthy Japanese infants.
2. Male or female infants aged 2-6 months (≥2 and <7 months) at the time of the first dose of investigational product (excluding hospitalized infants).
3. Infants whose parents or legal guardians have agreed to cooperate with the investigator during the study period.
4. The legal guardian signed and dated a written, informed consent form prior to the initiation of any study procedures.

Exclusion Criteria:

1. Any serious acute illness.
2. Any underlying cardiovascular, renal, hepatic, or hematologic disease, and/or developmental disorder.
3. History of possible Haemophilus influenzae type b (Hib) infection.
4. Previously diagnosed immunodeficiency.
5. Documented history of anaphylaxis to any ingredients of the investigational product (e.g., diphtheria toxoid).
6. A history of convulsions.
7. Previous administration of another Hib vaccine.
8. 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.
9. Prior participation in any clinical study or post-marketing clinical study.
10. Previously receipt of blood transfusions, gamma globulin preparations (except monoclonal antibody products not containing any components of Hib as antigens), systemic immunosuppressive therapy, or systemic corticosteroids, or a plan to receive any of these products during the study period.
11. Presence of thrombocytopenia or coagulopathy.
12. Children considered ineligible for the study for other reasons by the investigator or subinvestigator.