Gefitinib, an epidermal growth factor receptor–tyrosine kinase inhibitor (EGFR-TKI), is commonly used as a treatment for non–small cell lung cancer (NSCLC). Typically, patients are switched to another treatment once disease progression occurs on gefitinib; however, a study presented by In-Jae Oh, MD, PhD, assistant professor, Chonnam National University Hwasun Hospital in the Republic of Korea, at the Conference on Molecular Origins in Lung Cancer, suggests that there may be value in attempting a second regimen of gefi tinib after observing progressive disease with at least one cytotoxic treatment.
In Oh’s study, patients with NSCLC were put on gefitinib treatment until their disease progressed. They were then given at least one cycle of chemotherapy before reinitiating treatment with gefi tinib. Out of six patients who had partial responses to initial treatment with gefitinib, two had partial responses to the second treatment and three had stable disease. Among the nine patients who had stable disease after the first treatment with gefi tinib, two had partial responses and five had stable disease again after the second treatment. The overall disease control rate with the second treatment of gefi tinib was 80%.
Oh noted that a number of factors were possible indicators for a patient’s likelihood of responding to a second treatment of gefitinib, including activation of a mutation of the epidermal growth factor receptor (EGFR) gene, good response to initial EGFR-TKI for more than 3 months, and the adenocarcinoma’s histology. Being a female never-smoker also seemed to be a significant factor, as 10 of the 12 patients who had favorable responses fit this profile.
“After failure with gefi tinib and subsequent chemotherapy, we can try gefitinib again, especially for the patients who had previously responded to gefitinib,” said Oh. “This strategy will keep some patients from the toxicities of chemotherapy and help maintain the quality of life for several months,” he noted. According to Oh, if patients do not respond well to another round of gefitinib, treatment can always be switched.