EV71 vaccine shows sustained efficacy in Chinese children
The Vigoo Enterovirus 71 vaccine showed sustained efficacy in protecting children from hand, foot and mouth diseases, researchers in China found.
“Recently, large EV71 epidemics have occurred almost exclusively in the Asia-Pacific region, including Taiwan, mainland China, Hong Kong, Malaysia, Vietnam, Singapore and Thailand, which has become a serious threat to the public health,” Mingwei Wei, of the department of epidemiology and biostatistics, school of public health at Nanjing Medical University, Nanjing, China, and colleagues wrote. “Most of the hospitalized EV71-associated hand, foot and mouth disease cases with complications occurred in children younger than 5 years of age, while the severe or fatal EV71-associated neurological diseases are most susceptible to children less than 3 years of age, which is why the pathogen has captured much attention.
“In the first year of follow-up, the EV71 vaccine provided a high efficacy against EV71-associated hand, foot and mouth diseases in young children and infants, which has been reported previously. However, the long-term efficacy of this EV71 vaccine still needed to be evaluated, which is pivotal for the need of booster injections, licensing and clinical application.”
In a 2012 phase 3 study, researchers randomly assigned 10,245 children aged 6 to 35 months to two doses of the vaccine (n = 5,120) or placebo. They administered the second dose 28 days after the first, followed by 12 months of surveillance. Wei and colleagues then conducted a follow-up study over the course of 2 years, collecting throat, stool and anal swabs to identify cases of hand, foot and mouth disease.
The vaccine’s overall efficacy was 94.84% (95% CI, 83.53-98.38) in the total follow-up period, and 100% in the second year (95% CI, 84.15-100). There were no serious adverse events, and the children’s mean neutralizing antibody geometric titers remained at high levels for the entire follow-up period.
“The Vigoo EV71 vaccine could induce a sustained high level of antibodies and protection against EV71-associated hand, foot and mouth diseases for at least 2 years in healthy Chinese children, and with a good safety profile,” Wei and colleagues wrote. “These findings might play an important role in its licensing, clinical application and the decision-making on massive immunization on EV71 vaccine for controlling EV71-associated hand, food and mouth diseases epidemic in the future.” – by Andy Polhamus
Disclosure: Wei reports no relevant financial disclosures. Please see the full study for a complete list of all other researchers’ relevant financial disclosures.