A DOUBLE-BLIND, PLACEBO-CONTROLLED STUDY OF THE EFFECTS OF EPTASTIGMINE ON SCOPOLAMINE-INDUCED COGNITIVE DEFICITS IN HEALTHY MALE-SUBJECTS

This double-blind, placebo-controlled, crossover study examined the ef fects of two single doses of eptastigmine, a novel cholinesterase inhi bitor, on scopolamine-induced cognitive deficits in 24 healthy male vo lunteers. Each subject received the following treatment sequences, sep arated by at least 1 week, in a randomly assigned order: [GRAPHICS] A battery of computerized cognitive tests, lasting approximately 1 h, we re administered 30 min after the i.m. scopolamine/placebo injection. S ubjective visual analogue scale ratings were undertaken immediately pr ior to the first treatment (eptastigmine/placebo) and on completion of the cognitive test battery. In addition, blood samples were taken imm ediately following the subjective ratings, and at 2 h (prior to the sc opolamine/placebo injection), to determine peripheral acetylcholineste rase and butyrylcholinesterase activity. Scopolamine-induced deficits were found on a number of the cognitive tests and subjective ratings. Neither dose of eptastigmine significantly reversed or diminished thes e impairments. The two doses of eptastigmine produced the anticipated mean levels of red blood cell acetylcholinesterase inhibition (20 mg = 23 per cent; 32 mg = 37 per cent).