Serum amyloid P and CPHPC complex

Serum amyloid P and CPHPC complex. Molecular model showing a molecule of the anti-amyloid drug CPHPC (spheres) bound to each of the five subunits of a serum amyloid P (SAP) molecule (shown here as both ribbons and spacefilled models, colourful). CPHPC is a small molecule able to strip amyloid P (AP) from deposits by reducing levels of circulating SAP. It can be used to help treat amyloidosis, a disease caused by a build-up of amyloid (insoluble fibrous protein aggregates) in body tissues that leads to organ failure. The symmetrical nature of CPHPC allows it to bind to two SAP subunits from different SAP molecules. This allows five molecules of CPHPC to bind two SAP pentamers together and it is this mechanism of action that potently removes SAP from amyloid deposits in the tissues. This behaviour may also provide a new approach for treating both systemic amyloidosis and diseases associated with local amyloid, including Alzheimer's disease and type 2 diabetes.