It is estimated that there are more than 400,000 patients worldwide with wtATTR amyloidosis and 50,000 patients worldwide with hATTR amyloidosis. In both forms of the disease, patients can experience a spectrum of clinical manifestations affecting multiple organs, most commonly the heart and peripheral nerves. TTR protein (healthy form) is produced primarily in the liver and serves as a carrier for thyroxin and retinol binding protein (a transporter for vitamin A).
The investigational humanized monoclonal antibody PRX004 is designed to target and clear the non-native transthyretin aggregates (misTTR) associated with disease pathology that underlies both wtATTR and hATTR, without affecting the native, or normal tetrameric form of the protein (TTR).
It is generally accepted that, at the time of diagnosis, affected peripheral organs in ATTR patients (both wtATTR and hATTR amyloidosis) contain amyloid deposits. These deposits, together with prefibrillar species, are believed to cause organ dysfunction and failure. Existing therapies do not address amyloid deposition and are ineffective or untested in moderate-to-advanced cardiomyopathy in patients who are at highest risk of mortality due to amyloid deposition in the heart.