An orally available, synthetic small molecule with potential antineoplastic activity. AVN944 inhibits inosine monosphosphate dehydrogenase (IMPDH), an enzyme involved in the de novo synthesis of guanosine triphosphate (GTP), a purine molecule required for DNA and RNA synthesis. Inhibition of IMPDH deprives cancer cells of GTP, resulting in disruption of DNA and RNA synthesis, inhibition of cell proliferation, and the induction of apoptosis. AVN944 appears to have a selective effect on cancer cells in that deprivation of GTP in normal cells results in a temporary slowing of cell growth only. IMPDH is overexpressed in some cancer cells, particularly in hematological malignancies. Check for active clinical trialsusing this agent. or A drug used to treat depression. It may also be used to treat panic or anxiety disorders and certain types of pain, and to help people quit smoking. Aventyl increases the levels of norepinephrine and other natural chemicals in the brain. This helps improve mood and may reduce a person’s craving for nicotine. It is a type of tricyclic antidepressant. Also called nortriptyline and Pamelor.