Quantification of Tezepelumab in rat plasma by Bio-analytical Stability Indicating Method Development and Validation using LCMS and its Implementation to Pharmacokinetics

Tezepelumab, marketed under the trade name Tezspire, is a human monoclonal antibody used for the treatment of asthma. The present study aimed to develop a simple, economical, robust, and highly sensitive analytical method for the estimation of Tezepelumab in plasma samples obtained from male Wistar rats, using Abciximab as the internal standard. The chromatographic analysis was performed with a total runtime of 7.0 minutes, with Tezepelumab eluting at 3.115 minutes. The method demonstrated excellent linearity over the concentration range of 12.5–100.00 ng/mL, with a correlation coefficient (R²) of 0.999. The intra- and inter-assay precision showed %CV values below 15% across five quantification levels, indicating high reproducibility. All bioanalytical validation parameters were in accordance with USFDA guidelines and found to be within acceptable limits. Stability studies conducted at various time intervals confirmed the method’s reliability under different conditions. Furthermore, the peak plasma concentrations were determined as a function of time during the intravenous pharmacokinetic study, validating the suitability of the method for pharmacokinetic evaluation of Tezepelumab.