V1B receptor antagonist for use in the treatment of patients having an elevated AVP level and/or an elevated copeptin level

A method of treating a human patient with depressive symptoms and/or anxiety symptoms comprising predicting a treatment response to a V1B receptor antagonist in the human patient by determining the copeptin concentration in a blood sample of said patient, wherein an elevated copeptin concentration compared to copeptin concentration in individuals not suffering from anxiety and/or depressive symptoms and being at least 5 pmol/L is indicative for the patient responding to a treatment with a V1B receptor antagonist, and administering a V1B receptor antagonist to the patient if the elevated copeptin concentration has been determined in the blood sample, wherein the patient is determined to have the elevated copeptin concentration, and wherein a V1B receptor antagonist is administered to the patient.