Targeted therapies for the treatment of cancer

Background: In contrast to conventional cytotoxic chemotherapy and radiation therapy, a new method of targeted cancer therapeutics is being directed towards molecular pathways that underlie the malignant phenotype. These therapies target specific tumor cell receptors or signaling events that are critical to tumor progression while reducing toxicity to normal cells. Data sources: The purpose of this review is to highlight several examples of novel targeted therapeutics that are currently approved by the FDA for treatment of patients with cancer. Rituxan is a humanized monoclonal antibody that binds to the CD20 antigen present on B cell lymphomas and is currently approved for the treatment of patients with relapsed or refractory low-grade CD20 positive follicular lymphoma. The humanized anti-HER-2/neu herceptin is approved for use in patients with metastatic breast cancer that demonstrates overexpression of HER-2/neu. Finally, Gleevec is a tyrosine kinase inhibitor that inhibits abl-specific phosphorylation and is approved for use in select patients with chronic myelogenous leukemia that is refractory to interferon therapy. Conclusions: The lessons learned from the use of these therapeutics will add to the growing knowledge of mechanistic approaches to the treatment of patients with cancer based upon targeted therapies, and herald a bright future that will improve the lives of patients with cancer. (C) 2003 Excerpta Medica, Inc. All rights reserved.