A synthetic derivative of glutamic acid (alpha-phthalimido-glutarimide) with teratogenic, immunomodulatory, anti-inflammatory and anti-angiogenic properties. Thalidomide acts primarily by inhibiting both the production of tumor necrosis factor alpha (TNF-alpha) in stimulated peripheral monocytes and the activities of interleukins and interferons. This agent also inhibits polymorphonuclear chemotaxis and monocyte phagocytosis. In addition, thalidomide inhibits pro-angiogenic factors such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), thereby inhibiting angiogenesis. OR A drug used with another drug to treat multiple myeloma in patients who have just been diagnosed. It is also used to treat a painful skin disease related to leprosy. It is being studied in the treatment of other types of cancer. Thalidomide may help the immune system kill cancer cells. It may also prevent the growth of new blood vessels that tumors need to grow. It is a type of antiangiogenesis agent and a type of immunomodulating agent. Also called Synovir and Thalomid.