 Gefitinib is well endured by humans, and treatment resulted in a symptom improvement rate of 43% (with 95% confidence in a 33%–53% interval) for patients that received 250 mg of Gefitinib and 35% (with 95% confidence in a 26%–45% interval) for those that received 500 mg.In the trial, epidermal growth factor receptor showed a rapid response to the inhibitor, as demonstrated by the improvement of the cancer symptoms.In each group, improvements were noted after a single week of epidermal growth factor receptor tyrosine kinase inhibitor treatment.