Pharmacokinetics of the selective benzodiazepine antagonist Ro 15-1788 in man.

The pharmacokinetics of the selective benzodiazepine antagonist Ro 15-1788 has been studied in 6 healthy male volunteers following a single intravenous dose of 2.5 mg. The drug was only slightly bound to plasma proteins (40 +/- 8%, mean +/- SD). A negligible amount (less than 0.2% of the dose) of unchanged drug was recovered in urine. Hepatic elimination was rapid, as shown by a short t1/2 of 0.9 +/- 0.2 h, and high total plasma and blood clearances of 691 +/- 216 ml/min and 716 +/- 199 ml/min, respectively. The fast decline of plasma levels from about 60 to 2 ng/ml accounts for the short-lasting reversal of benzodiazepine-induced sedation by Ro 15-1788.