This is a single-center, double blind, randomized, placebo-controlled, parallel group study
of bear bile pill, as add-on therapy in MDD patients conducted in Shang Hai Mental Health
Center. The purpose of this study is to determine the efficacy and safety of bear bile pill
in reducing symptoms of depression in Major Depressive Disorder (MDD)patients with inadequate
response to current antidepressant therapy. Following a screening period, subjects who meet
the entry criteria will be randomized to treated with either placebo or 450mg bear bile pill
three times daily for 8 weeks.