摘要SARS-CoV-2 infection is a global public health threat.Vaccines are considered amongst the most important tools to control the SARS-CoV-2 pandemic.As expected,deaths from SARS-CoV-2 infection have dropped dramatically with widespread vaccination.However,there are concerns over the duration of vaccine-induced protection,as well as their effectiveness against emerging variants of concern.Here,we constructed a recombinant chimpanzee adenovirus vectored vaccine expressing the full-length spike of SARS-CoV-2(AdC68-S).Rapid and high levels of humoral and cellular immune responses were observed after immunization of C57BL/6J mice with one or two doses of AdC68-S.Notably,neutralizing antibodies were observed up to at least six months after vaccination,without substantial decline.Single or double doses AdC68-S immunization resulted in lower viral loads in lungs of mice against SARS-CoV-2 challenge both in the short term(21 days)and long-term(6 months).Histopathological examination of AdC68-S immunized mice lungs showed mild histological abnormalities after SARS-CoV-2 infection.Taken together,this study demonstrates the efficacy and durability of the AdC68-S vaccine and con-stitutes a promising candidate for clinical evaluation.