Emerging drugs for non-small cell lung cancer.

Lung cancer is the leading cause of cancer death in the world. Therapeutic improvements caused by recent cytotoxic agents seem to have reached a plateau. New therapeutic strategies are, therefore, necessary to improve the cure rate. These include receptor-targeted therapy, signal transduction or cell-cycle inhibition, angiogenesis inhibitors, cyclooxygenase-2 (COX-2) inhibitors, gene therapy and vaccines. The antiepidermal growth factor receptor (EGFR) group includes compounds acting on the extracellular domain of EGFR, such as IMC-C225 and trastuzumab; small molecules inhibiting EGFR phosphorylation, such as ZD 1839 and OSI-774; or compounds that interfere with one of the downstream steps, such as mitogen-activated protein kinase kinase (MEK) inhibitors. Farnesyl transferase inhibitors, such as SCH66336, and protein kinase C inhibitors, such as ISIS 3521, have also shown antitumour activity. Antiangiogenesis inhibitors include matrix metalloprotease inhibitors (MMPIs), suchs as marimastat, AG3340, BAY 12-9566, BMS-275291 and Col-3. Antiangiogenic agents offer great potential for the treatment of lung cancer, as shown in preclinical models, whereas emerging data suggest that there are limits to their use as monotherapy in advanced disease. Molecules targeting vascular endothelial growth factor (VEGF) or its receptor (VEGFR) also seem to control tumour progression and may prolong survival. COX-2 inhibitors are another class of agents currently under evaluation in clinical trials for their chemoprevention role in subjects at high lung cancer risk, and also in patients with non-small cell lung cancer (NSCLC) in combination with standard chemotherapeutics. Genetic and immunologic therapies represent two additional promising modalities. All of these therapies are in different phases of clinical testing and have shown encouraging activity alone or in combination with chemotherapy drugs.