All non-small cell lung cancer patients on the EGFR inhibitors Tarceva erlotinib and Iressa gefitinib eventually develop resistance to the drugs and progress. A predictive model developed by a team of cancer researchers suggests simply altering the dosing regimens of the drugs may be sufficient to prevent or delay resistance.

Two small molecule EGFR inhibitors are marketed to treat NSCLC. Roche, its Genentech Inc. unit and Astellas Pharma Inc. market Tarceva in the U.S. and EU. AstraZeneca plc markets Iressa in the EU. The standard regimen is the maximum tolerated once daily dose of drug until progression occurs.