The path of Iressa Resistance

A report in the Journal of Clinical Investigation provides evidence that cancer cells develop resistance to Iressa gefitinib, an epidermal growth factor receptor inhibitor, by upregulating insulin-like growth factor-1.¹ Although the paper showed that the resistance can be overcome by inhibiting both receptors, companies working in the space had mixed views on whether the resistance mechanism is common to other epidermal growth factor receptor inhibitors and whether the findings would be widely applicable to human cancers.

There was agreement that the data bolster the rationale for using multiple growth factor inhibitors to treat cancer, and that it could provide markers to predict patient response...