- This study evaluated the effectiveness of group interpersonal psychotherapy (IPT-G) for patients suffering from moderate to severe major depressive disorder (MDD), and who responded to antidepressant drugs during the acute phase treatment. Subjects were allocated into two groups: in the study group subjects entered IPT-G while in the comparison group subjects continued with standard treatment. All subjects were assessed five times during and 6 months after the termination of the IPT-G in a double-blind, matched-control design. Subjects who participated in the IPT-G demonstrated significant improvement of their depressive symptoms compared to those who received the standard treatment both during the group therapy and in a 6-month follow-up period. Our preliminary results suggest that IPT in a group setting might be effective for a subset of patients who respond to antidepressant medication. Small group of patients, lack of different types of treatment as control groups.