Intramuscularly administered herpes zoster subunit vaccine has no effects on fertility, pre- and post-natal development in Sprague-Dawley rats

•An investigational shingles vaccine (gE/AS01) is under development.•Potential developmental and reproductive toxic effects were assessed in rats.•Female fertility, fetal and offspring development were unaffected by the vaccine.•Male mating performance and fertility were unaffected by the vaccine. The herpes zoster subunit vaccine (HZ/su) is an investigational vaccine for the prevention of shingles, a disease caused by the varicella zoster virus (VZV). It is composed of recombinant VZV glycoprotein E (gE) and AS01. We assessed the potential toxic effects of gE/AS01 and AS01 alone on female and male fertility, and on embryo-fetal, pre- and post-natal development in Sprague-Dawley rats. Females were immunized before pairing and during gestation. Half of the pregnant rats were used for embryo-fetal investigations. The ones that gave birth were immunized during lactation and offspring were analysed. In a male fertility study, rats were immunized before pairing. After mating, the untreated females were sacrificed and the fetuses examined. In addition, male fertility parameters were evaluated. Results indicated that female mating performance and fertility, pre- and post-natal survival and offspring development, male mating performance and fertility were unaffected by intramuscular administration of the zoster candidate vaccine gE/AS01.