Tarceva is a drug commonly used to treat several types of non-small cell lung cancer. Often Tarceva is used used together with gemcitabine to treat pancreatic cancer. Tarceva is a type of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor. Also called CP-358,774, erlotinib, erlotinib hydrochloride, and OSI-774.