One Full or Two Fractional Doses of Inactivated Poliovirus Vaccine for Catch-up Vaccination in Older Infants: A Randomized Clinical Trial in Bangladesh.

Abstract

BACKGROUND:

The polio eradication endgame called for the removal of trivalent oral poliovirus vaccine (OPV) and introduction of bivalent (types 1 and 3) OPV and inactivated poliovirus vaccine (IPV). However, supply shortages have delayed IPV administration to tens of millions of infants, and immunogenicity data are currently lacking to guide catch-up vaccination policies.

METHODS:

We conducted an open-label randomized clinical trial assessing 2 interventions, full or fractional-dose IPV (fIPV, one-fifth of IPV), administered at age 9-13 months with a second dose given 2 months later. Serum was collected at days 0, 60, 67, and 90 to assess seroconversion, priming, and antibody titer. None received IPV or poliovirus type 2-containing vaccines before enrolment.

RESULTS:

A single fIPV dose at age 9-13 months yielded 75% (95% confidence interval [CI], 6%-82%) seroconversion against type 2, whereas 2 fIPV doses resulted in 100% seroconversion compared with 94% (95% CI, 89%-97%) after a single full dose (P < .001). Two doses of IPV resulted in 100% seroconversion.

CONCLUSIONS:

Our study confirmed increased IPV immunogenicity when administered at an older age, likely due to reduced interference from maternally derived antibodies. Either 1 full dose of IPV or 2 doses of fIPV could be used to vaccinate missed cohorts, 2 fIPV doses being antigen sparing and more immunogenic.

CLINICAL TRIAL REGISTRATION:

NCT03890497.

• Authors: Asma B Aziz, Harish Verma, Visalakshi Jeyaseelan, Mohammad Yunus, Samarea Nowrin, Deborah D Moore, Bernardo A Mainou, Ondrej Mach, Roland W Sutter, Khalequ Zaman
• Journal: The Journal of infectious diseases (J Infect Dis) Vol. 226 Issue 8 Pg. 1319-1326 (10 17 2022) ISSN: 1537-6613 [Electronic] United States
• PMID: 35575051 (Publication Type: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)
• Copyright: © The Author(s) 2022. Published by Oxford University Press on behalf of Infectious Diseases Society of America.

Chemical References

• Antibodies, Viral
• Poliovirus Vaccine, Inactivated
• Poliovirus Vaccine, Oral

Topics

• Aged
• Antibodies, Viral
• Bangladesh
• Humans
• Immunization Schedule
• Infant
• Poliomyelitis (prevention & control)
• Poliovirus
• Poliovirus Vaccine, Inactivated
• Poliovirus Vaccine, Oral
• Vaccination (methods)