New drug developments in the Netherlands. "Tetracyclic" psychotropic drugs.

Based on qualitative and quantitative EEG findings, the psychotropic properties of GB-94, GC-46, and GC-94 were predicted. According to the EEG model, GB-94 was predicted to be similar to amitriptyline and GC-46 t( imipramine. GC-94 was found to be much less effective on the CNS than GB-94 and GC-46 and was predicted to have "stimulatory" clinical effects similar to desipramine. The clinical trials demonstrated that GB-94 is indeed an antidepressive psychotropic compound similar to amitriptyline. GB-94 in lower dosages was also found to be effective in anxiety syndromes. In some schizophrenics GB-94 showed some therapeutic effects, while in others it obviously exacerbrated the psychotic symptomatology. GC-94 was not found to be significantly effective in a heterogenous psychiatric population. Only slight improvement in some schizophrenic patients was observed However, a noticeable worsening in the symptomatology of manic and hypomanic patients was seen. The study demonstarted that GC-94 indeed has a central stimulatory effect, but no minor or major tranquilizer properties or sedative antidepressive qualities were observed. GC-46 was tried in only three subjects. Based on this pilot trial, no conclusion can be made about the psychotropic properties of this compound. Our quantitative pharmaco-EEG and clinical trials clearly demonstrated the significant value of quantitative EEG in early screening of psychoactive drugs in order to predict their clinical values and effective dosage ranges.