[Experimental study on the activity of the triazolo-benzodiazepine GP 55 129 compared with diazepam and placebo in healthy volunteers].

Animal studies have led to the hypothesis that GP 55 129 sedates less than diazepam while possessing the same anxiolytic qualities. This hypothesis was tested on 60 healthy, emotionally labile volunteers. The drugs were administered once in a double-blind test at a dosage of 10 mg diazepam and 4 mg GP 55 129. A video camera and very difficult tests were used to induce anxiety in the subjects. Multivariate analysis of the 15 factors in the adjective check list showed a global drug effect (P less than 0.025). Comparison of the profiles of mean values indicated that the subjects under diazepam felt more tired and groggy than those with GP 55 129 and placebo medication at the dosage level used. However, the individual comparisons were not statistically significant. There was a significant reduction for both drugs in relation to the placebo in the "excitation" factor of the polarity profile. Free description showed a typical tranquilizer profile for both drugs. Significant achievement decrements (concentration-performance test by Düker, Viennese determination instrument, pursuit rotor, critical flicker fusion frequency) were not evident for either drug after a single dose of the strength we were examining. Subjective verbal tests yielded some significant sex differences without showing any interaction between sex and drug. To summarize the results, it can be said that the new substance possesses tranquilizing effects marked by a general suppression of excitation. The profile differences on the adjective check list showed a trend toward confirmation of the hypothesis, but must be replicated in further tests.