SV2A and Alzheimer disease: New SV2A PET tracers are being continuously developed for in vivo quantification of SV2A brain levels in animal models and patients with AD to optimise the tracer’s (a) binding affinity for SV2A, (b) brain uptake, (c) metabolism, (d) in vivo kinetics, and (e) half-life, which should neither require on-site cyclotron tracer synthesis nor be too long [11,234,236,237,238,239,240,241].