Safety, Immunogenicity and Lot-to-Lot Consistency of Sabin-Strain Inactivated Poliovirus Vaccine in 2-Month-Old Infants: A Double-Blind, Randomized Phase III Trial
Yan Zheng,
Zhifang Ying,
Yanxiang Zou,
Taotao Zhu,
Dinggu Qian,
Weixiao Han,
Ya Jiang,
Zhiwei Jiang,
Xingyan Li,
Jianfeng Wang,
Jin Lei,
Li Xu,
Deyu Jiang,
Changgui Li,
Xiaoqiang Liu
Affiliations
Yan Zheng
Vaccine Clinical Research Center, Yunnan Provincial Center for Disease Control and Prevention, Kunming 650034, China
Zhifang Ying
Respiratory Virus Vaccine Department, Biological Product Institute, National Institutes for Food and Drug Control, Beijing 100050, China
Yanxiang Zou
Vaccine Clinical Research Center, Yunnan Provincial Center for Disease Control and Prevention, Kunming 650034, China
Taotao Zhu
Clinical Research Department, Sinovac Biotech Co., Ltd., Beijing 100089, China
Dinggu Qian
Vaccine Clinical Research Project Office, Qiubei County Center for Disease Control and Prevention, Wenshan Zhuang and Miao Autonomous Prefecture 663299, China
Weixiao Han
Clinical Research Department, Sinovac Biotech Co., Ltd., Beijing 100089, China
Ya Jiang
Vaccine Clinical Research Project Office, Mile County Center for Disease Control and Prevention, Honghe Hani and Yi Autonomous Prefecture 652399, China
Division of Acute Infectious Disease Control and Prevention, Yanshan County Center for Disease Control and Prevention, Wenshan Zhuang and Miao Autonomous Prefecture 663299, China
Jianfeng Wang
Clinical Research Department, Sinovac Biotech Co., Ltd., Beijing 100089, China
Jin Lei
Immunization Program Division, Gejiu County Center for Disease Control and Prevention, Honghe Hani and Yi Autonomous Prefecture 661099, China
Li Xu
Quality Assurance Department, Sinovac Biotech Co., Ltd., Beijing 100089, China
Deyu Jiang
R&D Department, Sinovac Life Sciences Co., Ltd., Beijing 102629, China
Changgui Li
Respiratory Virus Vaccine Department, Biological Product Institute, National Institutes for Food and Drug Control, Beijing 100050, China
Xiaoqiang Liu
Vaccine Clinical Research Center, Yunnan Provincial Center for Disease Control and Prevention, Kunming 650034, China
Background: The Sabin-strain-based inactivated poliovirus vaccine (sIPV) plays an important role in poliomyelitis eradication in developing countries. As part of the phase III clinical development program, this study aimed to evaluate the safety, immunogenicity and lot-to-lot consistency of the sIPV in 2-month-old infants. Method: We conducted a phase III, randomized, double-blind, positive-controlled trial in which 1300 healthy infants were randomly assigned to four groups in a 1:1:1:1 ratio to receive one of the three lots of the sIPV or the control IPV at 2, 3 and 4 months of age. Serum samples were collected before the first dose and 30 days after the third dose of vaccination to assess the immunogenicity. Solicited local and systemic reactions were recorded within 7 days and unsolicited adverse events within 30 days after each vaccination. Results: Of the 1300 randomized infants, 1190 infants completed the study and were included in the per-protocol population. The seroconversion rates in the three lots of the sIPV were 95.67%, 97.03% and 95.59%, respectively, for type 1; 94.33%, 93.73% and 92.88%, respectively, for type 2; and 98.67%, 99.67% and 99.32%, respectively, for type 3. The ratios of GMTs for poliovirus types 1, 2 and 3 of each pair of lots were all between 0.67 and 1.50, therefore meeting the predefined immunological equivalence criteria. For the seroconversion rate of poliovirus types 1, 2 and 3, the pooled sIPV group was non-inferior to the IPV group. The incidence of solicited and unsolicited adverse reactions (ARs) was similar in the pooled sIPV lots and the IPV group, and most of them were mild to moderate in severity. Non-vaccine-related serious adverse events (SAEs) were reported. Conclusions: Three consecutive lots of sIPV demonstrated robust and consistent immunogenicity. The safety and tolerability of the sIPV was acceptable and similar to that of the IPV.
