Genital herpes is a sexually transmitted disease representing a major global health
concern. Currently, there is no approved vaccine and existing antiviral therapies
exhibit limited efficacy. Herein, we describe an intranasal (IN) vaccine comprised
of HSV-2 surface glycoproteins gD2 and gB2 formulated in a nanoemulsion adjuvant (NE01-gD2/gB2).
Using the HSV-2 genital herpes guinea pig model, we demonstrate that IN NE01-gD2/gB2
induces higher levels of neutralizing antibody compared to a monovalent IN NE01-gD2
vaccine, but less than an intramuscular (IM) Alum/MPL-gD2 vaccine. Following intravaginal
(IVag) challenge with HSV-2, the group immunized with IN NE01-gD2/gB2 exhibited significantly
reduced acute and recurrent disease scores compared to placebo recipients. Significantly,
latent virus was only detected in the dorsal root ganglia of 1 of 12 IN NE01-gD2/gB2-vaccinated
animals compared to 11 of 12 placebo recipient. In the therapeutic model, IN NE01-gD2/gB2
immunized guinea pigs exhibited a significant reduction in the recurrent lesions scores
(64%, p<0.01), number of animal days with disease (64%, p<0.01), number of animals
with viral shedding (50%, p<0.04) and reduction in virus positive vaginal swabs (56%,
p<0.04), These data suggests that the treatment may be effective in treating chronic
disease and minimizing virus transmission. These results warrant advancing the development
of IN NE01-gD2/gB2 as both a prophylactic and therapeutic vaccine against HSV-2.