Li-Min Huang1, Cheng-Hsun Chiu2, Nan-Chang Chiu3, Chien-Yu Lin4, Ming-Ta Li4, Tsun-Yung Kuo5, Yi-Jen Weng6, Erh-Fang Hsieh6, I-Chen Tai7. 1. Department of Pediatrics, National Taiwan University Children's Hospital, Taipei, Taiwan. 2. Department of Pediatrics, Chang Gung Children's Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan. 3. Department of Pediatrics, MacKay Children's Hospital, Taipei, Taiwan; Department of Medicine, Mackay Medical College, New Taipei City, Taiwan. 4. Department of Pediatrics, Hsinchu MacKay Memorial Hospital, Hsinchu, Taiwan. 5. Department of Biotechnology and Animal Science, National Ilan University, Ilan, Taiwan. 6. Clinical Development Department, Medigen Vaccine Biologics Corp., Taipei, Taiwan. 7. Clinical Development Department, Medigen Vaccine Biologics Corp., Taipei, Taiwan. Electronic address: kathytai@medigenvac.com.
Abstract
BACKGROUND: To fight against enterovirus A71 (EV-A71)-associated diseases, vaccine development was initiated in Taiwan focusing on two-month-old infants. METHODS: We conducted a phase II, double-blind, randomised, placebo-controlled study on infants and children aged two months to 11 years. This study was conducted in 4 parts (2a, 2b, 2c, and 2d) with age de-escalation sequentially. Two doses were administered with a 28-day or 56-day interval. Participants aged two months to <two years received a booster dose at one year after the first dose. During the surveillance period, solicited adverse events (AEs) and unsolicited AEs were recorded for safety evaluation. Blood samples were collected for neutralising antibody assay at various times. Immune persistence and booster effects were also assessed. RESULTS: A total of 363 children completed the study. Most AEs were mild and unrelated to treatment. No vaccine-related serious adverse events (SAEs) were reported. Geometric mean titres (GMTs) of serum neutralising antibody titres increased profoundly. Most participants in the vaccine groups achieved defined seroprotection (neutralization titre ≥ 1:32) after the second vaccination and persisted for two years. Furthermore, the EV-A71 vaccine could provide a cross-reaction against other EV-A71 strain genotypes: B5, C4a, C4b, and C5. CONCLUSIONS: The mid dose of the EV-A71 vaccine elicited high immune response and were tolerable in participants aged between two months and 11 years in all dosing groups.
RCT Entities:
BACKGROUND: To fight against enterovirus A71 (EV-A71)-associated diseases, vaccine development was initiated in Taiwan focusing on two-month-old infants. METHODS: We conducted a phase II, double-blind, randomised, placebo-controlled study on infants and children aged two months to 11 years. This study was conducted in 4 parts (2a, 2b, 2c, and 2d) with age de-escalation sequentially. Two doses were administered with a 28-day or 56-day interval. Participants aged two months to <two years received a booster dose at one year after the first dose. During the surveillance period, solicited adverse events (AEs) and unsolicited AEs were recorded for safety evaluation. Blood samples were collected for neutralising antibody assay at various times. Immune persistence and booster effects were also assessed. RESULTS: A total of 363 children completed the study. Most AEs were mild and unrelated to treatment. No vaccine-related serious adverse events (SAEs) were reported. Geometric mean titres (GMTs) of serum neutralising antibody titres increased profoundly. Most participants in the vaccine groups achieved defined seroprotection (neutralization titre ≥ 1:32) after the second vaccination and persisted for two years. Furthermore, the EV-A71 vaccine could provide a cross-reaction against other EV-A71 strain genotypes: B5, C4a, C4b, and C5. CONCLUSIONS: The mid dose of the EV-A71 vaccine elicited high immune response and were tolerable in participants aged between two months and 11 years in all dosing groups.