Differential immunogenicity of a live attenuated SARS-CoV-2 vaccine candidate by subcutaneous inoculation in hamsters and nonhuman primates: A cautionary note

Animal models play a crucial role in preclinical vaccine testing, with mice and hamsters commonly used. This study evaluated the immunogenicity of a novel live attenuated SARS-CoV-2 vaccine candidate, CDO-7 N-1, which was administered subcutaneously to hamsters and macaques. Despite both species producing robust responses upon intranasal inoculation, the vaccine induced robust neutralizing antibody responses only in hamsters and failed to elicit a detectable immune response in macaques. This discrepancy highlights the importance of selecting appropriate animal models and optimizing vaccination routes for accurately predicting human vaccine efficacy, thereby guiding future vaccine development strategies.