As previously shown for A/Singapore/INFIMH-16-0019/2016 (Fig. 3B), rTET-NA based on A/Perth/16/2009 N2 elicited dose-dependent NAI titers that were boosted by AF03 (Fig. 5B); both 3 and 45 μg rTET-NA adjuvanted doses induced NAI titers comparable to pre-infection with A/Perth/16/2009 virus at time of challenge, with no significant differences between these groups. This evidence concerns the gene XK and infection.