The present invention relates to a compound of formula (3Z, 5S)-5-(hydroxymethyl)-1-[(2' -methyl-1, 1' -biphenyl-4-yl)carbonyl]pyrrolidin-3-one O-methyloxime, and/or an active metabolite thereof having antagonist action at the oxytocin receptor and/or vasopressin V1a receptor, to processes for their preparation, pharmaceutical compositions containing them and their use.