In the per-protocol population , @ weeks of treatment with bitopertin was associated with a significant reduction of negative symptoms in the @-mg/d ( mean -LSB- SE -RSB- reduction in negative symptoms score , -@ % -LSB- @ % -RSB- ; P = @ ) and @-mg/d ( mean -LSB- SE -RSB- , -@ % -LSB- @ % -RSB- ; P = @ ) bitopertin groups , a significantly higher response rate and a trend toward improved functioning in the @-mg/d group when compared with placebo ( mean -LSB- SE -RSB- , -@ % -LSB- @ % -RSB- ) .