Purpose

RATIONALE: Preclinical studies indicate that sorafenib is a potent inhibitor of Raf kinase in vitro and in vivo, with significant dose-dependent, anti-tumor activity in four different human tumor types including colon, pancreatic, lung, and ovarian. This activity was cytostatic in nature and was maintained if dosing was continued. That is, tumor growth is suspended while the drug is administered but returns to baseline rates when the agent is withdrawn. Therefore, the optimal schedule will be an uninterrupted one. To assess the activity of sorafenib in a timely manner and with a meaningful interpretation, a randomized discontinuation design was adopted in the present trial, conducted in a population who were potentially sensitive to sorafenib. PURPOSE: This randomized phase II trial is studying sorafenib to see how well it works compared to placebo in treating patients with refractory non-small cell lung cancer.