February 16, 2021
The Zika virus candidate, Ad26.ZIKV.001, a replication-incompetent human adenovirus serotype 26 (ad26) vector showed promising safety and immunogenicity in a phase I clinical trial. Researchers say the vaccine warrants further development should the need reemerge. The findings are published in Annals of Internal Medicine.
Zika virus (ZIKV) infection is transmitted via mosquito or sexually and may cause severe congenital disease after maternal-fetal transmission. The incidence of Zika virus has declined since the 2015-2016 outbreak, but geographic expansion of the Aedes aegypti mosquito to areas where population-level immunity is low poses a substantial risk for future epidemics. Currently, no vaccine is available.
Researchers from Janssen Vaccines and Prevention and Beth Israel Deaconess Medical Center randomly assigned 100 healthy participants to either a 1- or 2-dose regimen of Ad26.ZIKV.001 or placebo to assess the safety and immunogenicity of the Zika vaccine candidate. They found that 2 doses of Ad26.ZIKV.001 were safe, caused mild to moderate reactogenicity, and induced persistent neutralizing antibody responses.