RPA1 and anthrax infection: Having established immunogenicity and efficacy in a rabbit model, we proceeded to test DPX-rPA in cynomolgus macaques, a model species that closely recapitulates human anthrax disease.17 We first assessed development of functional antibodies by TNA as well as vaccine safety in non-human pimates (NHPs) vaccinated once (Study Day 0) or twice (Study Days 0 and 56) with DPX-rPA (5 μg) as compared with AVA (diluted 1:4) administered twice (Study Days 0 and 28).