Overview of Lapatinib: Chemistry, Pharmacology, and Clinical Applications

The present study focuses on the development and validation of a sensitive, accurate, and reproducible bioanalytical method for the estimation of Lapatinib in active pharmaceutical ingredient (API) form and marketed formulations using human plasma. Lapatinib, a dual tyrosine kinase inhibitor used in the treatment of HER2-positive breast cancer, requires precise quantification in biological matrices for effective pharmacokinetic and bioequivalence studies. A high-performance liquid chromatography (HPLC) method coupled with UV detection was developed for the extraction and quantification of Lapatinib from plasma samples. The method was optimized using appropriate sample preparation techniques, including protein precipitation, to ensure high recovery and minimal matrix interference. Method validation was carried out in accordance with USFDA and ICH guidelines, evaluating parameters such as selectivity, linearity, accuracy, precision, recovery, matrix effect, and stability under various conditions. The developed method demonstrated excellent linearity over a concentration range suitable for pharmacokinetic studies, with correlation coefficients (R²) consistently greater than 0.998. Accuracy and precision were within acceptable limits, with %RSD less than 15%. The method proved robust, sensitive, and specific, making it suitable for routine analysis of Lapatinib in clinical and regulatory settings. This validated method can be effectively applied for bioavailability and bioequivalence studies, as well as for therapeutic drug monitoring in clinical research.