Researchers have closed a randomized clinical trial comparing gefitinib (Iressa) vs. placebo following chemotherapy and radiation for patients with non-small cell lung cancer (NSCLC) that had spread only to nearby tissues or lymph nodes. Review of interim data indicated that gefitinib would not improve survival.
The clinical trial was sponsored by the National Cancer Institute (NCI), and was conducted by a network of researchers led by the Southwest Oncology Group (SWOG), Ann Arbor, Mich. AstraZeneca Pharmaceuticals LP, Wilmington, Del., which manufactures gefitinib, provided the agent for the trial under the Clinical Trials Agreement with NCI for the development of gefitinib. Iressa is a drug that inhibits an enzyme (tyrosine kinase) present in lung cancer cells, as well as other cancers and normal tissues, that appears to be important to the growth of cancer cells.
Based on a review of the limited data available from the Phase III clinical trial, the Data Monitoring Committee overseeing the trial (known as S0023) recommended the closure, as the trial would not meet its primary endpoint of improved survival. Detailed results from the study will be presented at the American Society of Clinical Oncology Annual Meeting (ASCO) on May 14, 2005.
The study was designed to assess whether maintenance therapy with gefitinib -- gefitinib given to help keep cancer in control -- would improve overall survival and progression-free survival as compared to placebo in patients with stable or responding disease. These patients had inoperable stage III NSCLC and already had completed the combined chemotherapy regimen of cisplatin and etoposide with radiation, followed by docetaxel. A total of 672 patients in this study were to be randomized to one of two treaent arms following chemotherapy and radiation: one arm would receive gefitinib daily and the other arm would receive a placebo daily. As of March 10, 2005, 611 patients were entered and 276 were randomized to one of the two arms.