Modified synthesis of erlotinib hydrochloride

Globally Approved EGFR Inhibitors: Insights into Their Syntheses, Target Kinases, Biological Activities, Receptor Interactions, and Metabolism

Targeting the EGFR with small-molecule inhibitors is a confirmed valid strategy in cancer therapy. Since the FDA approval of the first EGFR-TKI, erlotinib, great efforts have been devoted to the discovery of new potent inhibitors. Until now, fourteen EGFR small-molecule inhibitors have been globally approved for the treatment of different types of cancers. Although these drugs showed high efficacy in cancer therapy, EGFR mutations have emerged as a big challenge for these drugs. In this review, we focus on the EGFR small-molecule inhibitors that have been approved for clinical uses in cancer therapy. These drugs are classified based on their chemical structures, target kinases, and pharmacological uses. The synthetic routes of these drugs are also discussed. The crystal structures of these drugs with their target kinases are also summarized and their bonding modes and interactions are visualized. Based on their binding interactions with the EGFR, these drugs are also classified into reversible and irreversible inhibitors. The cytotoxicity of these drugs against different types of cancer cell lines is also summarized. In addition, the proposed metabolic pathways and metabolites of the fourteen drugs are discussed, with a primary focus on the active and reactive metabolites. Taken together, this review highlights the syntheses, target kinases, crystal structures, binding interactions, cytotoxicity, and metabolism of the fourteen globally approved EGFR inhibitors. These data should greatly help in the design of new EGFR inhibitors.

Development and application of an HPLC method for erlotinib protein binding studies

PURPOSE

The aim of the present study was to develop a simple and rapid reversed-phase high performance liquid chromatographic method with UV detection for erlotinib hydrochloride quantification, which is applicable for protein binding studies.

METHODS

Ultrafilteration method was used for protein binding study of erlotinib hydrochloride. For sample analysis a simple and rapid reversed-phase high performance liquid chromatographic method with UV detection at 332 nm was developed. The mobile phase was a mixture of methanol, acetonitril and potassium dihydrogen phosphate buffer (15:45:40 %v/v) set at flow rate of 1.3 ml/min.

RESULTS

The run time for erlotinib hydrochloride was approximately 6 minutes. The calibration curve was linear over the range of 320-20000 ng/ml with acceptable intra- and inter-day precision and accuracy. The intra-day and inter-day precisions were less than 10% and the accuracies of intra and inter-day assays were within the range of 97.20-104.83% and 98.8-102.2% respectively.

CONCLUSION

Based on the obtained results, a simple, accurate and precise reversed-phase isocratic HPLC method with UV detection has been optimized and validated for the determination of erlotinib hydrochloride in biological samples.