Development and validation of a liquid chromatographic-mass spectrometric assay for the determination of sumatriptan in plasma.

Sumatriptan succinate is a novel compound currently in development for the acute treatment of migraine. During early studies in man a sensitive and selective assay was required, which had to be developed rapidly, to determine plasma concentrations following an intravenous infusion. Thermospray liquid chromatography-mass spectrometry combined with the advanced automated sample processor was selected to achieve this. Although the assay was required quickly criteria for intra- and inter-assay accuracies and precisions of +/- 10% had to be achieved. These were obtained only by using a co-eluting deuterium-labelled internal standard. Attempts to use a homologue as an internal standard, which did not co-elute with sumatriptan, gave inferior results. The assay was linear over the calibration range 2-50 ng/ml with a limit of quantification of 2 ng/ml. The application of the technique to the analysis of samples from a volunteer study is demonstrated.