A Study of ABT-888 in Combination With Temozolomide for Colorectal Cancer

People with colorectal cancer that cannot be cured by surgery are being asked to participate in this study.
The purpose of this study is to test the efficacy (effectiveness) of a new combination of drugs, ABT-888 and temozolomide for patients with colorectal cancer. Temozolomide acts by damaging deoxyribonucleic acid (DNA) in rapidly dividing cells, in other words, cancer cells. ABT-888 inhibits an enzyme called "PARP" which helps to fix damaged DNA. By inhibiting this enzyme, ABT-888 prevents cancer cells from repairing the damage caused by the temozolomide, and will hopefully increase the killing of cancer cells, and decrease the tumors in the body.
ABT-888 is an investigational or experimental anti-cancer agent that has not yet been approved by the Food and Drug Administration (FDA) for use in colorectal cancer.
This study will help find out what effects (good and bad) the combination of drugs, temozolomide and ABT-888 has on colorectal cancer.
This research is being done because it is not known if ABT-888 will increase the effectiveness of temozolomide for colorectal cancer.