Recently Approved Lung Cancer Drug Provides New First Line Treatment Option

Iressa blocks the activity of an enzyme responsible for regulating pathways implicated in the growth and survival of cancer cells.

Earlier this month, the FDA approved a new first line treatment option for patients with metastatic non-small cell lung cancer (NSCLC).

AstraZeneca’s gefitinib (Iressa) is an oral 250mg targeted monotherapy tablet taken once daily for NSCLC with tumors that have an epidermal growth factor receptor (EGFR) exon 19 deletions or exon 21 (L858R) substitution mutations, as detected by an FDA-approved test.

The drug is an EGFR tyrosine kinase inhibitor that blocks the activity of the EGFR tyrosine kinase enzyme that is responsible for regulating signaling pathways involved in the growth and survival of cancer cells. The drug received Orphan Drug Designation in August 2014 for the treatment of EGFR mutation-positive NSCLC.

“The approval of Iressa provides physicians and patients in the US with a new choice of first-line treatment for metastatic non-small cell lung cancer,” said Antoine Yver, head of Oncology, Global Medicines Development at AstraZeneca in a press release. “AstraZeneca is at the forefront of research into targeted therapies for EGFR mutated lung cancer and is committed to improving the outlook for patients at all stages of the disease.”

AstraZeneca joined with Qiagen to offer the therascreen EGFR companion diagnostic test for Iressa in the United States in order to quickly identify EGFR mutation status through a tumor tissue sample. The test can guide use of Iressa in patients with metastatic NSCLC.

A clinical trial enrolled 106 EGFR mutation-positive patients to receive Iressa. The overall response rate (ORR) was 70% (95% confidence interval [CI] 61% to 78%). The ORR in a blinded independent center review was 50% (95% CI 41% to 59%).

The most common adverse events were rash (44.9%), diarrhea (30.8%), vomiting (13.1%), asthenia, cough and dry skin (all 11.2%), and nausea (10.3%).