In this article, we will discuss Dacomitinib (Mechanism of Action). So, let’s get started.
Mechanism of Action
Dacomitinib is an irreversible inhibitor of the kinase activity of the human EGFR family (EGFR/HER1, HER2, and HER4) and certain EGFR activating mutations (exon 19 deletion or the exon 21 L858R substitution mutation). In vitro dacomitinib also inhibited the activity of DDR1, EPHA6, LCK, DDR2, and MNK1 at clinically relevant concentrations. Dacomitinib demonstrated dose-dependent inhibition of EGFR and HER2 autophosphorylation and tumor growth in mice bearing subcutaneously implanted human tumor xenografts driven by HER family targets including mutated EGFR. Dacomitinib also exhibited antitumor activity in orally-dosed mice bearing intracranial human tumor xenografts driven by EGFR amplifications.
Pharmacodynamics
Cardiac Electrophysiology
The effect of dacomitinib on the QT interval corrected for heart rate (QTc) was evaluated using time-matched electrocardiograms (ECGs) evaluating the change from baseline and corresponding pharmacokinetic data in
32 patients with advanced NSCLC. Dacomitinib had no large effect on QTc (i.e., >20 ms) at maximum dacomitinib concentrations achieved with VIZIMPRO 45 mg orally once daily.
Exposure-Response Relationships
Higher exposures, across the range of exposures with the recommended dose of 45 mg daily, correlated with an increased probability of Grade ≥3 adverse events, specifically dermatologic toxicities and diarrhea.