A conjugate vaccine using enantiopure hapten imparts superior nicotine-binding capacity

A leading nicotine conjugate vaccine was only efficacious for one-third of clinical trial participants, likely due in part to its use of racemic nicotine hapten, (±)-3'-AmNic. Immunization of male Wistar rats with (+)-, (-)-, or (±)-3'-AmNicSucTT and subsequent antibody immunoassays suggest that a vaccine using enantiopure (-)-3'-AmNic hapten imparts superior capacity to bind (-)-nicotine. Future nicotine vaccine clinical candidates must incorporate this design consideration (i.e., hapten enantiopurity) in order to maximize efficacy.