Fig. 4: Ad5-S-nb2 protects against SARS-CoV-2 infection in rhesus macaques.

a The viral loads in the pharyngeal swabs of non-vaccinated macaques. b The viral loads in the pharyngeal swabs in macaques at 4 weeks after IM vaccination with 1 × 10¹¹ vp Ad5-S-nb2. c The viral loads in the pharyngeal swabs in macaques at 4 weeks after IN vaccination with 5 × 10¹⁰ vp Ad5-S-nb2. d The viral loads in the pharyngeal swabs in macaques at 8 weeks after IM vaccination with 1 × 10¹⁰ vp Ad5-S-nb2. The genome copy numbers in the elution of the pharyngeal swabs were determined by quantitative reverse transcription PCR (qRT-PCR). The limit of detection was 200 copies ml⁻¹ and marked by the dot line. The data points were expressed as the mean of two technical replicates. Macaques C3, 116004, 134018, 063585, and 080066 were euthanatized on day 7 after challenge and were marked by hash symbol. Other macaques were euthanatized on day 10 after challenge. Macaques C1, C2, D1 and D2 were subsequently utilized for another study. e The viral loads calculated based on AUC in the pharyngeal swabs in macaques after challenge. Blue circles, macaques that received 1 × 10¹¹ vp Ad5-S-nb2 (IM); Dark cyan circles, macaques that received 1 × 10¹⁰ vp Ad5-S-nb2 (IM); Red circles, macaques that received mucosal vaccination (IN). Black circles, non-vaccinated macaques. Black lines reflect the mean AUC. Comparison between vaccinated (n = 9) and non-vaccinated (n = 5) macaques was conducted using Student’s t-test (unpaired, two-tailed). f–i The neutralizing antibody titers against SARS-CoV-2 before and after challenge in non-vaccinated macaques (f), high-dose IM vaccinated macaques (g), IN vaccinated macaques (h), and low-dose IM vaccinated macaques (i). The sera were examined by PRNT using SARS-CoV-2 (strain 2019-nCoV-WIV04). Source data are provided as a Source Data file.