Determination of partially protective dose of Ad-omicron in hamsters. (A) Syrian golden hamsters were vaccinated with log-fold dilutions of Ad-ο^IM in a homologous prime-boost regimen from 10² to 10⁸ infectious units (IU) followed by a challenge 70 days later with SARS-CoV-2 omicron BA.1. (B) Viral load in lung tissue as determined by PCR quantitation of sgRNA. Dots represent individual animals with box plots denoting median ± IQR and whiskers at min to max. This experiment was completed once (Ad-GFP^IM control group, n = 9; Ad-o^IM test group, n = 6). sgRNA, subgenomic RNA.