FDA Reviews Approval for Iressa™ May 2003: FDA approves lung cancer drug Iressa™ under accelerated approval program December 2004: AstraZeneca trials show no survival benefits when compared to placebo But statistically significant improvements for non-smoking and East Asian patient subpopulations In May 2003, the United States Food and Drug Administration (FDA) approved the use of AstraZeneca’s drug, Iressa™ (gefitinib), to treat non-small cell lung cancer. The accelerated approval was the result of promising initial clinical trials that had been conducted by the corporation. Further studies (see the update entitled “Iressa™”) indicated that patients with a particular mutation of the epidermal growth factor receptor (EGFR) were especially receptive to treatment with Iressa™. Non-smokers and East Asians with this type of lung cancer were more likely to have the EGFR mutation than other patient populations. However, a later in-house study by AstraZeneca in December, 2004 concluded that Iressa™ did not confer any better rates of survival than a placebo. Though examination of the trial data indicated that subpopulations of patients that were non-smokers or had East Asian ancestry did show statistically significant signs of improvement., the company decided to discontinue promoting the drug in North America and to withdraw its application for approval in the European Union. Furthermore, the FDA has decided to review its approval of the drug. Iressa’s™ reversal of fortune illustrates many of the challenges facing pharmacogenomics. Should patient populations be constructed using genetic markers that correlate with superior drug response? Should a drug company market a drug if it only benefits a small portion of the patient population? The still-developing Iressa™ story may very well illuminate answers to these fundamental questions. © 2005 Prentice Hall Inc. / A Pearson Education Company / Upper Saddle River, New Jersey 07458