Analysis of pregabalin at therapeutic concentrations in human plasma/serum by reversed-phase HPLC.

A selective and sensitive HPLC method is described for assay of the new antiepileptic drug pregabalin in serum/plasma. Following acetone precipitation of the sample, the drug was derivatized with picryl sulfonic acid (PSA) before chromatography on a C8 column. No interference from coadministered antiepileptics has been observed. The assay is calibrated over the range 0.5 mg/L to 8 mg/L. In addition to qualitative and quantitative validation data for the assay, concentration measurements in predose samples from a group of patients with dose escalated to 600 mg/d pregabalin are presented. The drug concentrations measured were in the range 2.8-8.2 mg/L at steady state. The method is robust and will be suitable for monitoring pregabalin therapy.