ADH-1 (brand name Exherin) is a small, cyclic pentapeptide vascular-targeting drug. It was developed by Adherex Technologies.
ADH-1 selectively and competitively binds to and blocks N-cadherin, which may result in disruption of tumor vasculature, inhibition of tumor cell growth, and the induction of tumor cell and endothelial cell apoptosis. N-cadherin, a cell- surface transmembrane glycoprotein of the cadherin superfamily of proteins involved in calcium-mediated cell–cell adhesion and signaling mechanisms; may be upregulated in some aggressive tumors and the endothelial cells and pericytes of some tumor blood vessels.
In 2006, Adherex and NCI formed a Clinical Trial Agreement stating that NCI will sponsor clinical trials of ADH-1 in a variety of cancer types. ADH-1 received orphan drug status from the FDA in 2008.
In a pilot study (phase I trial), ADH-1 intravenous pretreatment before chemotherapy in metastatic melanoma completely destroyed tumors in half of patients. It is being investigated for advanced extremity melanoma in phase II trials.