Immunogenicity and safety of an adjuvanted inactivated polio vaccine, IPV-Al, following vaccination in children at 2, 4, 6 and at 15-18 months

Vaccine. 2020 May 6;38(21):3780-3789. doi: 10.1016/j.vaccine.2020.02.066. Epub 2020 Apr 6.

Abstract

Background: Availability of affordable inactivated polio vaccines (IPV) is of major importance to meet the increasing global supply needs. The results presented here demonstrate non-inferiority of a reduced-dose, aluminium hydroxide-adjuvanted IPV (IPV-Al) to standard IPV.

Methods: A phase 3, observer-blinded, randomised, clinical trial was conducted in Panama in infants who received either IPV-Al (n = 400) or standard IPV (n = 400) at age 2, 4 and 6 months. In the booster trial, subjects received a single dose of IPV-Al at age 15-18 months. The primary endpoint was type-specific seroconversion, defined as an antibody titre ≥4-fold higher than the estimated maternal antibody titre and a titre ≥8, one month after the primary vaccination series. In the booster trial, the primary endpoint was the type-specific booster effects (geometric mean titre (GMT) post-booster (Day 28)/GMT pre-booster (Day 0).

Results: Seroconversion rates following primary vaccination with IPV-Al vs IPV were: 96.1% vs 100% (type 1); 100% vs 100% (type 2); and 99.2% vs 100% (type 3) respectively. IPV-Al was non-inferior to IPV, as the lower 95% confidence limits of the treatment differences were above the pre-defined -10%-point limit: 3.94% (-6.51; -2.01) for type 1; 0.0% (-1.30; -1.37) for type 2; -0.85 (-2.46; 0.40) for type 3. The booster effects for the group primed with IPV-Al versus the group primed with IPV were 25.3 vs 9.2 (type 1), 19.1 vs 6.5 (type 2) and 50.4 vs 12.5 (type 3). IPV-Al had a comparable safety profile to that of IPV.

Conclusions: Non-inferiority of IPV-Al to standard IPV with respect to seroconversion after vaccination at 2, 4 and 6 months was confirmed for all three poliovirus serotypes. A robust booster response was demonstrated following vaccination with IPV-Al, regardless of the primary vaccine received. Both vaccines were well tolerated. ClinicalTrials.gov identifiers: NCT03025750 and NCT03671616.

Funding: Bill & Melinda Gates Foundation.

Keywords: Affordable IPV; Aluminium hydroxide adjuvant; Booster vaccination; Immunogenicity; Polio; Primary vaccination; Standalone adjuvanted IPV.

Publication types

  • Clinical Trial, Phase III
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Viral
  • Female
  • Humans
  • Immunization Schedule
  • Immunization, Secondary*
  • Immunogenicity, Vaccine*
  • Infant
  • Male
  • Panama
  • Poliomyelitis / prevention & control*
  • Poliovirus Vaccine, Inactivated / administration & dosage*
  • Poliovirus Vaccine, Inactivated / adverse effects
  • Vaccination

Substances

  • Antibodies, Viral
  • Poliovirus Vaccine, Inactivated

Associated data

  • ClinicalTrials.gov/NCT03671616
  • ClinicalTrials.gov/NCT03025750