In an open multicenter trial (7 hospitals) 85 schizophrenic patients were treated with 3-fluoro-6-(4-methyl-piperazinyl)- 11H -dibenz[b,e]azepine ( fluperlapine , NB 106-689) during 20 days. Symptomatology was documented with the AMDP system on days 0, 1, 5, 10, 15 and 20. A mean daily dosage of about 400 mg caused a significant antipsychotic effect and pronounced improvement of depressive symptoms. Fluperlapine was well tolerated. Extra-pyramidal side-effects were very rare.