Issues in the assessment of treatment response in panic disorder with special reference to fluvoxamine.

Assessment of treatment response in panic disorder is complicated by the multidimensional aspects of panic disorder and agoraphobia, the short-term benefits from nonspecific aspects of treatment, and placebo response. Response to treatment with psychological and pharmacologic treatments of panic disorder is reviewed in this context. The experience of several Phase III studies of fluvoxamine in the treatment of panic disorder is examined as an illustrative example. When the response to placebo or comparison treatment in a study is high, no conclusion can be drawn about the true efficacy of the active treatment.