A Pilot Study of Metformin Therapy in Patients With Relapsed Chronic Lymphocytic Leukemia (CLL) and Untreated CLL

Metformin is an antidiabetic drug which is an inexpensive and generally well tolerated medication. More recently metformin has been shown to act against carcinomas by two mechanisms: 1) an indirect, insulin-dependent mechanism which sensitizes tissues to insulin, inhibits hepatic gluconeogenesis, and stimulates uptake of glucose in muscle, thereby reducing fasting blood glucose and circulating levels of insulin, lowering the pro survival activity of the insulin/INSR axis, and 2) a direct, insulin-independent mechanism which activates the AMP-activated protein kinase (AMPK) pathway and leads to inhibition of the mTOR pathway. Given the investigators preliminary published data on insulin and mTOR inhibition\[1\] metformin is an attractive candidate for a pilot clinical trial in CLL patients.