metformin + vandetanib

**metformin + vandetanib** is an investigational combination of two small molecule drugs: metformin, an oral antidiabetic agent primarily used for type 2 diabetes, and vandetanib, a selective tyrosine kinase inhibitor originally approved for medullary thyroid cancer. Vandetanib targets the vascular endothelial growth factor receptor (VEGFR), epidermal growth factor receptor (EGFR), and rearranged during transfection (RET) signaling pathways, inhibiting tumor angiogenesis and growth. Metformin decreases hepatic glucose production and improves insulin sensitivity. This combination has been explored in clinical trials as a potential therapy for certain kidney cancers, such as hereditary leiomyomatosis and renal cell cancer, based on a possible synergistic antitumor effect. Coadministration requires careful monitoring because vandetanib can significantly increase metformin blood levels by reducing its renal clearance, necessitating potential dose adjustments or additional patient monitoring.