Fig. 3: Qβ-fentanyl vaccines generate high-titer antibodies.

Anti-fentanyl endpoint dilution IgG titers generated after immunization with FENBB1, FENBB2, or FENBB3 fentanyl vaccine candidates or with the unconjugated Qβ control. Mice (n = 10, Balb/cJ, male and female) were immunized on days 0 and 21.