Pedvaxhib

Clinical Evaluation of PedvaxHIB – The Protective Efficacy Study

• In a randomized, double-blind, placebo-controlled study, the lyophilized formulation of PedvaxHIB was evaluated in 3486 Native American (Navajo) infants who completed the primary 2-dose regimen. Patients were randomly assigned to receive either 2 doses of PedvaxHIB or placebo with the first dose being at a mean of 8 weeks of age and the second dose administered approximately 2 months later; DTP and OPV were administered concomitantly.

• After a follow-up until 15 to 18 months of age, there was only 1 case of invasive Hib disease in the vaccine group and 22 cases in the vaccine group. The protective efficacy of lyophilized PedvaxHIB was calculated to be 93% (95% CI, 57-98; P =.001, two-tailed). In the time between the first and second doses, there were 0 cases in the vaccine group and 8 cases in the placebo group (P =.008, two-tailed).

• At the end of the study, patients in the placebo group were offered the vaccine and all patients were then followed for 2 years and 9 months. In the follow-up period, the estimated efficacy from person-days at risk was 96.6% (95% CI, 72.2-99.9) in children under 18 months of age and 100% (95% CI, 23.5-100) in children over 18 months of age).

Other Clinical Studies

• Safety and immunogenicity of lyophilized PedvaxHIB was evaluated in infants and children in studies conducted throughout the US. All age groups who received PedvaxHIB were found to be highly immunogenic.

• Among poor responders to nonconjugated PRP vaccines, lyophilized PedvaxHIB elicited antibody levels greater than 1.0 mcg/mL in children. 

• Another study included 34 children aged 27 to 61 months who developed invasive Hib disease despite previous vaccination with nonconjugated PRP vaccines. These children were randomly assigned to receive either lyophilized PedvaxHIB or a nonconjugated PRP vaccine at approximately 12 months after recovery from the disease. The antibody level of >1.0 mcg/mL was achieved by all children who receive PedvaxHIB vs 6 out of 20 children revaccinated with a nonconjugated PRP vaccine.

• PevaxHIB was also evaluated in children at high risk of Hib disease due to genetically-related deficiencies (Blacks who were Km(1) allotype negative and Caucasians who were G2m(23) allotype negative) and are considered hyporesponsive to nonconjugated PRP vaccines on this basis. All children vaccinated with lyophilized PedvaxHIB achieved anti-PRP levels of >1.0 mcg/mL.

Clinical Study – Liquid PedvaxHIB vs Lyophilized PedvaxHIB 

• In a randomized clinical study, 903 infants 2 to 6 months of age received either Liquid PedvaxHIB or lyophilized PedvaxHIB; DTP and OPV were administered concomitantly to most patients. Each formulation elicited similar antibody responses.

Interchangeability of Licensed Haemophilus b Conjugate Vaccines and PedvaxHIB 

• Published studies have shown that if PedvaxHIB is administered with other licensed Haemophilus b Conjugate Vaccines, the recommended number of doses to complete the series is determined by the other product and not by PedvaxHIB. PedvaxHIB may be interchanged with other licensed vaccines for the booster dose.

Use with Other Vaccines

• Clinical studies have shown that Liquid PedvaxHIB can be administered concomitantly with DTP, OPV, eIPV, Varivax, M-M-R II, or Recombivax HB.