FIG. 9.

Virus titers in the lungs of oseltamivir-resistant or -sensitive virus-infected mice treated by the repeated oral administration of oseltamivir or a single intranasal administration of CS-8958. Mice infected with oseltamivir-sensitive A/Yokohama/67/2006 clone 1 (a) or H274Y oseltamivir-resistant A/Yokohama/67/2006 clone 11 (b) were orally administered oseltamivir phosphate twice daily from 13 hpi with 1.0 mg/kg (dotted lines, triangles) or 10 mg/kg (dotted lines, squares), were intranasally administered CS-8958 once at 13 hpi at 0.057 μmol/kg (0.027 mg/kg; solid lines, triangles) or 0.17 μmol/kg (0.080 mg/kg; solid lines, squares), or were administered saline (solid lines, open circles). The viral titers (log₁₀ PFU/lungs) in the lungs were measured at 37, 61, and 85 hpi, and the lower limit of detection was 2.4 (log₁₀ PFU/lungs). Each plot represents the mean ± standard deviation (n = 3). For the plot indicated by “#,” the viral titer was calculated to be 2.4 (log₁₀ PFU/lungs) for 1 out of 3 mice because no viruses were recovered from the mouse lungs.