Pertussis Immunization

This is a Phase I/II, double-blind, randomized, active controlled, multi-centric clinical trial to assess the reactogenicity, safety and immunogenicity of a SIIPL DTwP-HepB-rPV-Hib vaccine in comparison with HEXASIIL® in healthy toddlers and infants. This trial is planned as a Phase I/II trial with two age cohorts to be enrolled sequentially, starting with healthy toddlers and subsequently extending to healthy infants. In Phase I of the trial, after at least one parent signs the informed consent and the participant's eligibility is confirmed, healthy toddlers aged 12-24 months will be randomized in a 2:1 ratio, to receive 0.5 mL of either of the vaccines intramuscularly in the upper anterolateral aspect of the thigh. Following vaccination, all toddlers will be observed at the site for minimum 30 (+15) minutes for any Iimmediate Adverse Event (IAE). Solicited Adverse Events (AEs) will be actively collected for 7 days post vaccination. Unsolicited AEs and Serious AEs will be collected throughout the trial from the time of signing informed consent till 28 days post vaccination. Blood samples for immunogenicity assessment will be obtained from all participating toddlers at Visit 1 (Prior to vaccination) and at Visit 4. A Data Safety Monitoring Board (DSMB) meeting will be convened for the evaluation of 7-day safety data in all participants. The DSMB shall review the safety data and provide recommendations to initiate Phase II of the trial. Additionally, Safety Review Comitte (SRC) will review the 24-hour safety data from the initial sentinel group (three participants) and give advice on progression to the subsequent enrolment in Phase I. After at least one parent signs the informed consent and the participant's eligibility is confirmed, all infants will be randomized in 2:1 ratio to receive a 3-dose primary vaccination series at 6, 10 and 14 weeks of age. Each participant will receive 0.5 mL of either vaccine intramuscularly in the upper anterolateral aspect of the thigh. Following each vaccination, all infants will be observed at the site for minimum 30 (+15) minutes for any IAEs. Active follow up for solicited AEs will be conducted over the 7-day period after each vaccination. Unsolicited AE/SAEs will be collected from signing of informed consent till Visit 10. Blood samples for immunogenicity assessment will be obtained from all participating infants at Visit 1 (Prior to vaccination) and at Visit 10.