FOLH1 and xerostomia: This approach popularized by the Homburg group uses a lower activity of 225Ac-PSMA (an average of 5.3 MBq) combined with a standard activity of 177Lu-PSMA to achieve an optimum antitumor effect without the undesirable severe xerostomia inducible by a standard activity of 225Ac-PSMA [89, 90].