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A concerted action on the part of international agencies and national governments has resulted in the near-eradication of poliomyelitis. However, both the oral polio vaccine (OPV) and the inactivated polio vaccine (IPV) have deficiencies which make them suboptimal for use after global eradication. OPV is composed of attenuated Sabin strains and stimulates robust immunity, but may revert to neurovirulent forms in the intestine which can be shed and infect susceptible contacts. The majority of IPV products are manufactured using pathogenic strains inactivated with formalin. Upon eradication, the production of large quantities of pathogenic virus will present an increased biosecurity hazard. A logical ideal endgame vaccine would be an inactivated form of an attenuated strain that could afford protective immunity while safely producing larger numbers of doses per unit of virus stock than current vaccines. We report here the development of an ionizing radiation (IR)-inactivated Sabin-based vaccine using a reconstituted Mn-decapeptide (MDP) antioxidant complex derived from the radioresistant bacterium Deinococcus radiodurans. In bacteria, Mn2+-peptide antioxidants protect proteins from oxidative damage caused by extreme radiation exposure. Here we show for the first time, that MDP can protect immunogenic neutralizing epitopes in picornaviruses. MDP protects epitopes in Polio Virus 1 and 2 Sabin strains (PV1-S and PV2-S, respectively), but viral genomic RNA is not protected during supralethal irradiation. IR-inactivated Sabin viruses stimulated equivalent or improved neutralizing antibody responses in Wistar rats compared to the commercially used IPV products. Our approach reduces the biosecurity risk of the current PV vaccine production method by utilizing the Sabin strains instead of the wild type neurovirulent strains. Additionally, the IR-inactivation approach could provide a simpler, faster and less costly process for producing a more immunogenic IPV. Gamma-irradiation is a well-known method of virus inactivation and this vaccine approach could be adapted to any pathogen of interest., Competing Interests: Two co-authors are employed by the Department of Defense. MJD is a Professor at the Uniformed Services University Health Sciences. Dr. Daly participated in all aspects of the project but he and his University have no control over funding. HNM is a Program Officer at one of the two funding agencies, DTRA. Dr. Meeks played a role in the conceptualization of the overarching research aims, in the analysis and interpretation of the data, and in manuscript editing. Dr. Meeks has no role in decisions regarding funding these types of applications that are submitted to DTRA. The two funding agencies provided support in the form of salaries for all authors with the exception of MJD who is a fully-funded Professor at USUHS and HNM who is a fully-funded employee at DTRA. The specific roles of these authors are articulated in the ‘author contributions’ section. The commercial nature of Biological Mimetics, Inc. does not alter our adherence to PLOS ONE policies on sharing data and materials.