To provide an effective, long-term and safe pharmaceutical composition for use in a method of treating treatment-
refractory or treatment-resistant depression in a patient diagnosed as having the depression.SOLUTION: A pharmaceutical composition for use in a method of treating treatment-resistant depression in a patient, wherein the pharmaceutical composition comprises esketamine and wherein the patient has not responded to at least two oral antidepressants in a current depressive episode, the pharmaceutical composition comprising: The method provides a pharmaceutical composition comprising: administering esketamine to the patient at least twice a week during a first
induction phase of at least 4 weeks; evaluating the patient during the first
induction phase; wherein the patient does not achieve a substantially
complete response to esketamine; and re-starting the patient with the highest tolerated
dose of esketamine in a second
induction phase of at least 4 weeks.SELECTED DRAWING: None