Agomelatine significantly reduced mean ( SD ) HARS total score ( agomelatine-placebo difference : @ -LSB- @ -RSB- , P < @ ) and had significant effects on secondary outcome measures , including psychic and somatic HARS subscales , response rate ( estimate -LSB- standard error -RSB- ) ( agomelatine-placebo difference : @ % -LSB- @ % -RSB- , P < @ ) , remission on the HARS ( agomelatine-placebo difference : @ % -LSB- @ % -RSB- , P = @ ) , Clinical Global Impressions-Severity of Illness scale ( CGI-S ) ( P < @ ) , functional impairment ( P < @ ) , and sleep quality ( P < @ ) .