A Study to Evaluate the Safety and Immunogenicity of Oral Polio Vaccine Type 2 in Infants and Children

• PRIMARY OBJECTIVE The primary objectives of the study are to assess the safety (serious adverse events [SAEs] and severe adverse events [AEs] grade 3 according to CTCAE 4.03 and immunogenicity (seroprotection rate) of a single dose of SABIN mOPV2 in healthy children aged 1 to 5 years old, and in infants at approximately 18 weeks of age after having been vaccinated with 3 doses of bOPV and 1 dose of IPV .
• SECONDARY OBJECTIVES

Secondary objectives are to assess:

• The safety (mild and moderate solicited and unsolicited AEs, Important Medical Events [IMEs], and laboratory deviation assessments) of one or two doses of SABIN mOPV2 in healthy children aged 1 to 5 years, and of 2 doses of SABIN mOPV2 in infants at approximately 18 and 22 weeks of age after having been vaccinated with 3 doses of bOPV and 1 dose of IPV.
• The immunogenicity (seroconversion rate, median and geometric mean antibody titers) of one or two doses of SABIN mOPV2 in healthy children aged 1 to 5 years old, and of two doses of SABIN mOPV2 in infants at approximately 18 22 weeks of age after having been vaccinated with 3 doses of bOPV and 1 dose of IPV.
• EXPLORATORY OBJECTIVES

Exploratory objectives are:

• To investigate viral shedding following the SABIN mOPV2 administration.
• Exploratory objectives may also include assessment of the genetic sequence heterogeneity and potential for neurovirulence (as measured in animal model(s)) of shed virus.
• To investigate viral shedding and neurovirulence of shed virus;
• To evaluate genetic reversion at position nt481 (primarily) and other secondary sites (e.g., nt2908).
• To investigate the priming responses of bOPV for mOPV2. (group 2 only) and the duration of induction of anti-polio type 2 neutralizing antibodies .

Inclusion criteria

• Children aged 1 to 5 years previously vaccinated with three or four doses of IPV (Group 1) or unvaccinated infants aged 6 weeks (-7 to +14 days) (Groups 2 and 3).
• For Groups 2 and 3 (enrolled at 6 weeks of age) infants must have been vaccinated with 3 doses of bOPV and one dose of IPV prior to administration of the study vaccine, and the last Polio vaccine must have been administered at least 4 weeks prior to the study vaccine.
• Healthy without obvious medical conditions that preclude the subject to be in the study as established by the medical history and physical examination.
• Written informed consent obtained from 1 or 2 parent(s) or legal guardian(s) as per country regulations.

Exclusion criteria

• For Group 1: polio vaccines within the 3 months prior to the administration of the study vaccine (number of previous polio vaccine doses to be documented). For Groups 2 and 3: polio vaccines prior to administration of the study vaccine other than 3 doses of bOPV and 1 dose of IPV .
• Any confirmed or suspected immunosuppressive or known immunodeficient condition including human immunodeficiency virus (HIV) infection.
• Family history of congenital or hereditary immunodeficiency.
• Major congenital defects or serious uncontrolled chronic illness (neurologic, pulmonary, gastrointestinal, hepatic, renal, or endocrine).
• Known allergy to any component of the study vaccines or to any antibiotics.
• Uncontrolled coagulopathy or blood disorder contraindicating intramuscular injections (of IPV).
• Administration of immunoglobulins and/or any blood products since birth or planned administration during the study period.
• Acute severe febrile illness at day of vaccination deemed by the Investigator to be a contraindication for vaccination (the child can be included at a later time if within age window and all in/exclusion criteria are met.).
• Member of the subject's household (living in the same house or apartment unit) has received OPV in the last 3 months.
• Subject who, in the opinion of the Investigator, is unlikely to comply with the protocol or is inappropriate to be included in the study for the safety or the benefit-risk ratio of the subject.