Poly(ADP-Ribose) polymerase (PARP) is a nuclear enzyme involved in repairing DNA damage, mediating cell death and regulating immune response. PARP activation occurs when cells are damaged in instances such as during chemotherapy, radiotherapy radiation therapy, stroke, head trauma and heart ischema. The multiple functions of PARP make it an attractive target for a variety of serious conditions including various types of cancer and neurodegenerative diseases.

In cancer patients, PARP inhibition may increase the therapeutic benefits of radiation and chemotherapy. Targeting PARP may prevent tumor cells from repairing DNA themselves and developing drug resistance, which may make them more sensitive to cancer therapies. In preclinical testing, PARP inhibitors have demonstrated the ability to increase the effect of various chemotherapeutic agents (e.g. methylating agents, DNA topoisomerase inhibitors, cisplatin), as well as radiation, against a broad spectrum of tumors (e.g. glioma, melanoma, lymphoma, colorectal cancer, head and neck tumors).

MGI PHARMA is focused on evaluating PARP inhibition as a chemotherapy and radiation therapy sensitizer. The Company has identified potent, small molecule, orally bioavailable, and highly brain penetrable PARP inhibitors and has a solid IP position, with more than 27 patents issued or pending. A lead clinical candidate compound has been selected and a phase 1 trial is being planned.