Gefitinib (ZD1839, Iressa®): a selective epidermal growth factor receptor-tyrosine kinase inhibitor

Objective: To provide a comprehensive review of the clinical pharmacology and toxicology of gefitinib, with particular attention to its use in early clinical trials.Data source: A PubMed search was conducted using the terms ZD1839, gefitinib, and epidermal growth factor receptor (EGFR). All data from this search were reviewed and other relevant papers identified. The abstracts from the annual meetings of the American Society of Clinical Oncology were also reviewed.Data extraction: The aim of the review was to be comprehensive and descriptive. The authors reviewed studies and case reports containing information deemed to be of interest.Conclusions: EGFR is expressed, overex-pressed, or disregulated in a variety of human solid tumors, resulting in an enhancement of tumor growth. Gefitinib is a selective reversible inhibitor of EGFR that has shown activity in several tumor types. As an oral agent, it is extensively metabolized in the liver through the cytochrome P450 enzyme system, particularly the isoenzyme...