Safety of primary immunization with a DTwP-HBV/Hib vaccine in healthy infants: a prospective, open-label, interventional, phase IV clinical study

Objective This study aimed to assess the safety of a fully liquid DTwP-HBV/Hib pentavalent vaccine (Eupenta(TM)) based on the occurrence of adverse events (AEs) following vaccination. Methods This was a prospective, open-label, single-arm, interventional phase IV study. A single intramuscular injection of the study vaccine was administered to infants at approximately 6, 10, and 14 weeks of age, and an end-of-study follow-up visit was scheduled at 18 weeks. Results In all, 3000 subjects were enrolled and received at least one dose of the study vaccine. Of these, 2717 (90.6%) experienced at least one AE. Immediate reactions, solicited and unsolicited AEs were respectively identified in 224 (7.5%), 2,652 (88.4%), and 1,099 (36.6%) subjects. The most prevalent solicited and unsolicited AEs comprised pain/tenderness and upper respiratory tract infection, respectively. Most AEs were mildly or moderately severe. Forty-one (1.4%) subjects had at least one serious AE (SAE); of these, two (0.1%) had two SAEs each, considered related to the study vaccine. Six (0.2%) subjects died due to unsolicited AEs, none of which were considered related to the study vaccine. No AEs were reported at the end-of-study follow-up visit. Conclusions The study vaccine had a safety profile similar to that reported in a previous clinical study, and did not result in an increased risk of AEs known to be associated with DTwP-based vaccines or previously unrecognized SAEs.