Immunogenicity of Two Different Sequential Schedules of Inactivated Polio Vaccine Followed by Oral Polio Vaccine Versus Oral Polio Vaccine Alone in Healthy Infants in China

• Published in: Journal of the Pediatric Infectious Diseases Society 2016-09, Vol.5 (3), p.287-296
• Main Authors: Li, Rong-Cheng, Li, Chang-Gui, Wang, Hai-Bo, Luo, Hui-Min, Li, Yan-Ping, Wang, Jian-Feng, Ying, Zhi-Fang, Yu, Wen-Zhou, Shu, Jean Denis, Wen, Ning, Vidor, Emmanuel
• Format: Article
• Language: English
• Subjects: Antibodies, Viral; China; Humans; Immunization Schedule; Infant; Poliomyelitis - prevention & control; Poliovirus Vaccine, Inactivated - immunology; Poliovirus Vaccine, Oral - immunology
• ISSN: 2048-7193; 2048-7207
• DOI: 10.1093/jpids/piv017

Background Two vaccination schedules where inactivated polio vaccine (IPV) was followed by oral polio vaccine (OPV) were compared to an OPV-only schedule. Methods Healthy Chinese infants received a 3-dose primary series of IPV-OPV-OPV (Group A), IPV-IPV-OPV (Group B), or OPV-OPV-OPV (Group C) at 2, 3, and 4 months of age. At pre-Dose 1, 1-month, and 14-months post-Dose 3, polio 1, 2, and 3 antibody titers were assessed by virus-neutralizing antibody assay with Sabin or wild-type strains. Adverse events were monitored. Results Anti-polio 1, 2, and 3 titers were ≥8 (1/dil) in >99% of participants, and Group A and Group B were noninferior to Group C at 1-month post-Dose 3 as assessed by Sabin strain-based assay (SSBA). In Group A 1-month post-Dose 3, there was no geometric mean antibody titers (GMT) differences for types 1 and 3; type 2 GMTs were ≈3-fold higher by wild-type strain-based assay (WTBA) versus SSBA. For Group B, GMTs were ≈1.7- and 3.6-fold higher for types 1 and 2 via WTBA, while type 3 GMTs were similar. For Group C, GMTs were ≈6.3- and 2-fold higher for types 1 and 3 with SSBA, and type 2 GMTs were similar. Antibodies persisted in >96.6% of participants. Adverse event incidence in each group was similar. Conclusions A primary series of 1 or 2 IPV doses followed by 2 or 1 OPV doses was immunogenic and noninferior to an OPV-only arm. SSBA was better at detecting antibodies elicited by OPV with antibody titers correlated to the number of OPV doses (NCT01475539).