A high-performance liquid chromatographic assay for CI-973, a new anticancer platinum diamine complex, in human plasma and urine ultrafiltrates.

CI-973 is a new platinum compound with antitumor properties that is currently undergoing phase II clinical trials. A high-performance liquid chromatographic (HPLC) assay was developed and validated for ultrafiltrates of human plasma and urine to support phase I clinical trials. Plasma ultrafiltrate (0.5 ml) was extracted using C18 solid-phase cartridges. Urine was diluted 10-fold and extracted first with SAX solid-phase cartridges and then with C18 cartridges. For both matrices, the eluate from the C18 cartridges was injected directly. A Whatman PAC 10 column (4.6 x 250 mm, 10-microns particle size) and ultraviolet detection at 205 nm were used for both analyses. The mobile-phase buffer was 0.05 M sodium perchlorate (pH 2.3). The mobile-phase acetonitrile:buffer ratio, column temperature, and flow rate were 89:11 (v/v), 40 degrees C, and 2.0 ml/min, respectively, for the plasma ultrafiltrate assay and 85:15 (v/v), 50 degrees C, and 1.0 ml/min, respectively, for the urine ultrafiltrate assay. Standard curves were linear from 0.25 to 500 micrograms/ml and from 1.0 to 250 micrograms/ml for the plasma and urine assays, respectively. The accuracy of the assay lay within 4.5% of the nominal values, and the precision was 6.2%; the recovery of CI-973 varied from 79.2% to 105%. CI-973 remains stable in plasma for at least 6 h, at room temperature, in ultrafiltrates of both matrices for at least 15 days at -72 degrees C, and in water for at least 6 months at -72 degrees C.

High-performance liquid chromatographic assay for CI-1004, a dual-inhibitor antiinflammatory agent, in rat, rabbit, dog, monkey and human plasma.

CI-1004 and PD 138389 (internal standard, I.S.), were isolated from rat, rabbit, dog, monkey and human plasma by solid-phase extraction with Bond-Elut C18 cartridges. Liquid chromatographic separation was achieved isocratically on a Zorbax Rx-C8 analytical column (250 mm x 4.6 mm I.D). The mobile phase consisted of acetonitrile-20 mM ammonium acetate (65:35, v/v), (pH 4.0). Column temperature was either 40 degrees C (human assay) or 45 degrees C and column effluent was monitored spectrophotometrically at 360 nm. Specificity, chromatographic performance parameters, system repeatability, recovery from matrix, linearity, precision, accuracy and stability were evaluated. Mean retention times (+/-S.D.) of CI-1004 and I.S. were 7.8+/-0.1 and 10.9+/-0.2 at 40 degrees C and 7.7+/-0.2 min and 10.7+/-0.2 min at 45 degrees C. No interfering peaks were observed at the retention time of CI-1004 throughout the validation process. Peak height ratios were proportional to CI-1004 over the concentration range of 7.5-5000 ng/ml in rat, rabbit and monkey plasma and 2.5-5000 ng/ml in dog and human plasma. Recovery of low, medium and high standards of CI-1004 ranged from 82.8-107% from all animal species and recovery of I.S. from rat, rabbit, dog and monkey plasma ranged from 77.5-82.0% and from human plasma was 111%. Assay precision for CI-1004 based on quality control samples was less than or equal to 8.5% C.V. with an accuracy (percentage relative error) of +/-4.7% for all species. Minimum quantitation limit of CI-1004 was 7.5 ng/ml for 0.2 ml rat, rabbit and monkey plasma samples and 2.5 ng/ml for 0.5 ml dog and human plasma samples. The method is suitable for studying the preclinical and clinical pharmacokinetics of CI-1004.