TTR and amyloidosis: Innovative work in determining whether circulating non-native TTR levels (which are breakdown products of the TTR tetramer) correlate with clinical status and treatment response in patients with ATTRv amyloidosis is currently underway and has shown promising mechanistic potential.73 The Scripps Research Institute has developed a peptide-based probe that specifically labels and quantifies non-native TTR levels in the blood (TTR oligomers).