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A sensitive isocratic HPLC method for the analysis of AWD 122-14 (1) in plasma and urine was developed. The extraction was processed on-line on a short column. The pharmacokinetics of 1 was studied in rats. The plasma concentration-time course was described by an 1-compartment-model. The pharmacokinetic parameters were estimated. The absorption and elimination of 1 are relatively fast. A single oral dose (D = 1 x 10(-5) mol/kg) was rapidly absorbed (absorption rate constant: kI = 6.85 h-1). The elimination rate constant is kE = 1.59 h-1. The absolute bioavailability of a single oral dose equals 11%. In rats 1 is mainly metabolized. Less than 5% of the dose is excreted in the urine as unchanged drug. The chemical structures of 10 of the 12 isolated metabolites were determined using high-resolution mass spectrometry.

The biotransformation of 3'-chloro-2'-(N-methyl-N-[(morpholino-carbonyl)methyl]aminomethyl)benzanilide hydrochloride (fominoben-HCl, PB 89 Cl, Noleptan) was investigated in man. The most substantial metabolites were quantified. The metabolite patterns of fominoben in urine and plasma are compared. Fominoben, is rapidly and extensively metabolized to many metabolites. At the time of the maximum plasma level. 2 h after an oral dose of 160 mg of 14C-PB 89 Cl, only 1.5% of the plasma radioactivity can be measured as the unchanged initial compound. No parent compound can be found in the urine, only in the stool some traces of fominoben can be detected. The biotransformation can be characterized by four main pathways: 1. cleavage reactions, 2. hydroxylations, 3. cyclisations, 4. conjugations. The reactions 1--3 proceed as well simultaneously as successively.

The pharmacokinetics of 3'-chloro-2'-(N-methyl-N-[(morpholino-carbonyl)-methyl]-aminomethyl)benzanilide-hydrochloride (P-B 89 Cl, fominoben-HCl, Noleptan) was studied in dog and rabbit following a dose of 3 mg/kg on i.v. and p.o. administration of the 44C-labelled compound. Absorption: The compound is absorbed fast in the dog and very fast in the rabbit. Practically the entire dose is absorbed by the two species. Maximum levels in blood: dog 0.5 microgram/ml, rabbit 0.8 microgram/ml, in the plasma: dog 0.6 microgram/ml, rabbit 1.2 microgram/ml at 1--2 h p.a. and 15--30 min p.a. Elimination: The elimination from blood and plasma proceeds biphasically. 1st half-life: 1--2 h, 2nd half-life: 19--27 h (higher values for the rabbit). The dog eliminates preponderantly via the bile with the faeces, the rabbit via the kidneys: Dog: 19% in urine and 63% in faeces, rabbit 79% in urine and 16% in faeces, measured up to 96 h p.a. One rabbit excreted 70% via the urine up to 7 h p.a. The half-lives of urinary elimination are very well comparable with the figures for plasma. Biotransformation: Plasma (maximum level): Dog: Visible amounts of parent compound (M0), Rabbit: Traces M0, much M2. Urine (0--24 h p.a.): Dog: Traces: M0, Rabbit: Traces M0, much M2.

The effect of 2 mg sublingual molsidomine was evaluated in a double-blind cross-over study and compared to placebo in 9 patients with stable angina pectoris and ST-lowering of greater than or equal to 1 mm in the exercise ECG. Assessment of exercise tolerance (Watt-minute product) and ST-lowering during exercise with the bicycle ergometer was correlated with simultaneously measured blood plasma levels. An increase of maximal Watt-minute product from mean = 308.3 (s mean - 45.4) to mean = 74.4 (s mean = 138.7) was found after 1 hour with effectiveness over 5 hours. ST-lowering while on molsidomine was decreased from mean = 2.5 mm (s mean = 0.3) to a minimum of mean = 0.7 mm (s mean = 0.28) during identical work load. Action on the ST segment lasted for 3 hours. Blood plasma levels of molsidomine correlated to the drug action with a maximum after one hour and a half life of 2.03 hours.