It is provided a catechol-O-methyltransferase (COMT) inhibitor for use in the prevention and/or treatment of transthyretin-associated amyloidosis. It is also provided a catechol-O-methyltransferase (COMT) inhibitor for use in the prevention and/or treatment of transthyretin-associated amyloidosis in combination therapy with another COMT inhibitor, a benzoxazole derivative, iododiflunisal, diflunisal, resveratrol, tauroursodeoxycholic acid, doxocycline, or epigallocatechin-3-gallate.