Patients newly diagnosed with metastatic non-small cell lung cancer (NSCLC) who received gefitinib (Iressa) had significantly higher response rates and longer progression-free survival compared with patients who received carboplatin plus paclitaxel (73.7 percent versus 30.7 percent and 10.8 months versus 5.4 months, respectively), according to results of a phase III trial conducted in Japan. The results were published in the June 24 New England Journal of Medicine.

All patients enrolled in the study had epidermal growth factor receptor (EGFR) mutations that were sensitive to the tyrosine kinase inhibitor (TKI) gefitinib. The patients did not have the resistant EGFR mutation T790M, and they had not been previously treated with chemotherapy.

The researchers, led by Dr. Makoto Maemondo of the Miyagi Cancer Center in Miyagi, Japan, believe that this study establishes the clinical benefit of an EGFR tyrosine kinase inhibitor as first-line therapy in patients with NSCLC and sensitive EGFR mutations.“If gefitinib is administered as second-line or third-line treatment,” he and his colleagues wrote, “patients may miss the opportunity to receive treatment because of rapidly progressive disease during or after first-line treatment.”