Researchers at the US National Institutes of Health have closed a clinical trial of AstraZeneca’s non-small cell lung cancer agent, Iressa (gefitinib) early, saying that interim data suggest that the product did not increase survival in the group of patients in question.

The Phase III trial, which was sponsored by the National Cancer Institute, aimed to determine whether maintenance therapy with Iressa (to help keep cancer in control) would improve overall survival and progression-free survival versus placebo in patients with stable or responding disease. The 672 patients had inoperable, stage III NSCLC and already had completed a combined chemotherapy regimen. Detailed results from the study will be presented at the American Society of Clinical Oncology annual meeting next month.

“The interim analysis indicates that even with accrual of more patients or with longer follow-up, the [Iressa] arm would not improve survival,” said Laurence Baker, one of the researchers. “Based on the analysis, the use of [Iressa] following chemotherapy and radiation should not be prescribed for this group of patients,” added Scott Saxman who oversees lung cancer clinical trials for the NCI.

AstraZeneca pulled Iressa from the US market late last year after no survival benefit was seen amongst patients taking the drug in a major clinical trial [[20/12/04b]]. The firm also withdrew the product’s European filing [[05/01/05a]].