Erlotinib is the usual first treatment for patients with non-small cell lung cancers (NSCLC) that have EGFR mutations. The drug often shrinks cancers, but eventually stops working.
Dacomitinib is an investigational drug that targets the same part of the cancer cell as erlotinib. It has been evaluated in several other clinical trials. In this study, researchers want to see if giving a higher dose of dacomitinib less often will be effective for shrinking NSCLC tumors or preventing them from growing. Investigators want to determine if this dosing schedule is safe in patients. Dacomitinib is taken orally (by mouth).