Metformin Lowers Death Risk in mRCC Patients on Sunitinib
The protective effect was not observed with other anti-diabetic medications.
Metformin use is associated with a survival advantage among patients receiving sunitinib for metastatic renal cell carcinoma (mRCC), according to new findings presented at the 2016 Genitourinary Cancers Symposium in San Francisco.
A team at Dana-Farber Cancer Institute in Boston led by Toni K. Choueiri, MD, came to this conclusion after analyzing pooled clinical trial data from 4,736 mRCC patients, of whom 644 (13.6%) were diabetic. Of these, 218 used metformin, 268 were on other anti-diabetic therapies, and 4,150 were not on anti-diabetic therapy.
Metformin did not impact overall survival (OS) or progression-free survival (PFS) compared with other anti-diabetic therapies in the overall cohort, but OS improved significantly among metformin users compared with patients on other anti-diabetic therapies, according to the researchers. Among sunitinib recipients, metformin users had an approximately 95% decreased risk of death compared with patients taking other anti-diabetic therapies. The investigators found no significant change in OS when they compared metformin users with patients not on anti-diabetic therapies.
Dr. Choueiri's group hypothesizes that the combination of metformin and sunitinib synergistically augment the AMPK (AMP-activated protein kinase) pathway, a central regulator of cellular and organismal metabolism.