HPLC-MS/MS method for quantitative determination of the novel dual inhibitor of FGF and VEGF receptors E-3810 in tumor tissues from xenograft mice and human biopsies.

We developed and validated a high-performance liquid chromatography-tandem mass spectrometry analytical method to measure E-3810, a novel dual inhibitor of fibroblast growth factor receptor 1 and vascular endothelial growth factor receptor 1-3 in tissues and determined the drug concentration in a biopsy of human breast cancer for the first time. The method is a modification of our previous one in plasma to study the clinical pharmacokinetics of the drug during the phase I/II trial. In view of the changes in matrix, we applied a partial validation protocol to determine recovery, sensitivity, range of linearity, precision, accuracy and stability of the method over three runs in a mouse tumor tissue and liver. The recovery of E-3810 from liver or tumor homogenate was >69%, and the lower limit of quantification was 5 ng/ml. The method was linear in the concentration range 5.0-500.0 ng/ml, as demonstrated by a determination coefficient R(2) ≥ 0.9955. The range of the calibration curve was appropriate for the analysis, as demonstrated by the accuracy, which was between 91.4% and 106.7%. Interday precision and accuracy on quality control samples at 9, 30 and 300 ng/ml were 3.1-11.2% and 98.3-111.4%, respectively. The assay was applied successfully to determine the intratumor concentration of E-3810 in different mouse xenograft tumor models and in a biopsy of a patient with breast cancer included in the phase I/II trial of the drug. In mouse tumors, the concentrations of E-3810 were higher than necessary to exert antitumor activity in vitro (1 µM). Even more of interest was the result obtained in a human biopsy of few milligrams, where E-3810 reached 4.9 µg/g (11 µM).

A first in human phase I study of the proteasome inhibitor CEP-18770 in patients with advanced solid tumours and multiple myeloma.

BACKGROUND: The safety, pharmacokinetics (PK) and pharmacodynamics of CEP-18770, a new peptide boronic acid proteasome inhibitor, have been investigated after intravenous administration on days 1, 4, 8 and 11 of every 21d cycle in patients with solid tumours and multiple myeloma (MM). PATIENTS AND METHODS: Thirty-eight patients were treated with CEP-18770 at escalating doses from 0.1 to 1.8mg/m(2) where 2 out of 5 patients showed dose limiting toxicities. The maximum tolerated/recommended dose (MTD/RD) of 1.5mg/m(2) was tested in 12 additional patients. Skin rash was dose-limiting and occurred in 53% of patients; other frequent toxicities were asthenia (29%), stomatitis (21%) and pyrexia (16%). No significant peripheral neuropathy was observed. PK in plasma was linear with a half-life of the elimination phase of 62.0±43.5h. Proteasome inhibition in peripheral blood mononuclear cells was dose related in MM patients; it was of 45.4±11.5% at the RD. CONCLUSIONS: CEP-18770 showed a favourable safety profile with lack of neurotoxicity and linear plasma PK. The definition of the optimal biological dose and schedule of treatment is actively pursued because of the high incidence of skin toxicity of the twice a week schedule.

Development and validation of a high-performance liquid chromatography-tandem mass spectrometry method for the determination of the novel inhibitor of angiogenesis E-3810 in human plasma and its application in a clinical pharmacokinetic study.

E-3810, 6-[[7-[(1-aminocyclopropyl)methoxy]-6-methoxy-4-quinolyl]oxy]-N-methyl-naphthalene-1-carboxamide, is a novel, potent, dual inhibitor of vascular endothelial growth factor and fibroblast growth factor receptors with antiangiogenic properties, now under early clinical evaluation as an anticancer agent. To investigate its clinical pharmacokinetics, a high-performance liquid chromatography-tandem mass spectrometry method was developed and validated to measure the drug in human plasma on the basis of simple protein precipitation with methanol after addition of deuterated E-3810 as internal standard. The method requires a small volume of sample (100 µl) and is rapid and selective, allowing good resolution of peaks in 5 min. It is sensitive, precise, and accurate, with overall precision, expressed as CV%, always ≤7.1%, accuracy in the range 92.7%-104.4%, and high recovery, close to 100%. The limit of detection is 0.01 ng/ml, and the lower limit of quantitation is 2.0 ng/ml. The assay was validated in the range from the lower limit of quantitation up to 500.0 ng/ml. This is the first method developed and validated for analyzing E-3810 in human plasma. The method has been successfully applied to study E-3810 pharmacokinetics in cancer patients with solid tumors who are receiving daily oral doses of the drug during the phase I trial.

Development and validation of a high-performance liquid chromatography-tandem mass spectrometry method for the determination of the novel proteasome inhibitor CEP-18770 in human plasma and its application in a clinical pharmacokinetic study.

CEP-18770, [(1R)-1-{[(2S,3R)-3-hydroxy-2-{[(6-phenyl-2-pyridinyl)carbonyl]amino}butanoyl]amino}-3-methylbutyl]boronic acid, is a novel proteasome inhibitor, now under early clinical evaluation as an anticancer agent. To investigate its clinical pharmacokinetics, a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed and validated to measure the drug in human plasma, based on simple protein precipitation with acetonitrile after the addition of irbesartan as internal standard. The method requires a small volume of sample (100 µl) and is rapid and selective, allowing good resolution of peaks in 5 min. It is sensitive, precise and accurate, with overall precision, expressed as coefficient of variation (CV%), always < 10.0%, accuracy in the range 93.8-107.7% and high recovery, close to 100%. The limit of detection is 0.01 ng/ml and the lower limit of quantitation (LLOQ) is 0.20 ng/ml. The assay was validated in the range from the LLOQ up to 50.00 ng/ml. This is the first method developed and validated for analyzing a proteasome inhibitor with a boronic-acid-based structure in human plasma. The method was successfully applied to study the pharmacokinetics of CEP-18770 in cancer patients with solid tumors or multiple myeloma who had received the drug as a short intravenous bolus during the initial Phase I trial.