FOLH1 and xerostomia: Although several PSMA ligands have been developed over the last decades, the search for novel tracers with optimized pharmacokinetic properties particularly for therapeutic purposes is still present, since some of the clinically used PSMA radioligand therapeutics e.g., [225Ac]Ac-PSMA-617 display some severe side effects, like xerostomia [12,13,39].