"This is the largest study in lung cancer comparing an oral biologic therapy to chemotherapy, and shows, for the first time, that an oral biologic therapy is just as effective as chemotherapy," said Kim, the study's corresponding author. "Based on our findings, I'm hopeful that Iressa can return as a treatment for lung cancer in the United States, offering this some patients a therapy with far fewer side effects."
Lung cancer is the leading cause of cancer death in the United States, according to the American Cancer Society. In 2008, approximately 215,000 people will be diagnosed with lung cancer and approximately 114,000 people will die from the disease.
To best appreciate these findings, it's important to remember Iressa's history, said Kim. Iressa, a once-daily, oral tablet, was the first in a new class of anti-cancer drugs known as EGFR tyrosine kinase inhibitors (TKI) to become commercially available after two Phase II trials found the drug to be efficacious. Iressa was fast-tracked to the FDA and received approval May 5, 2003 as a single agent treatment for patients whose advanced lung cancer had continued to progress despite treatment with platinum-based and docetaxel chemotherapy.
However, in 2005, a large randomized lung cancer study reported that Iressa failed to significantly improve survival in patients with non-small cell lung cancer when compared to placebo. Ultimately, the drug's labeling was altered by the FDA; only cancer patients who had already taken the medicine and whose physicians believed it was helping them were allowed to receive the drug. No new lung cancer patients in the United States were given the drug after this time. However, Iressa remained an available therapy in other countries around the world.
The study also should offer both physicians and patients some confidence in another biological oral therapy, erlotinib, commercially known as Tarceva, that hits similar targets as Iressa and is commercially available for the treatment of lung cancer in the second line setting, explained Kim.
The study was funded by AstraZeneca, makers of Iressa. Dr. Kim has received research funding from, and served as a consultant for, both AstraZeneca and Sanofi-Aventis, the makers of docetaxel.
The Phase III international study enrolled 1,466 lung cancer patients from 149 centers in 24 countries. Of those enrolled, 1,433 were evaluable. All had either locally advanced or metastatic disease and had been previously treated for their cancer. Patients were randomized to receive either Iressa (250 milligrams daily) or docetaxel (75 mg/m2) every three weeks. The study had two primary survival endpoints: in all treated patients and in those whose tumors had high EGFR gene copy number, explained Kim.
Contact: Laura Sussman
713-745-2457 | lsussman [at] mdanderson [dot] org