TTR and Acute hepatic porphyria: Indeed, patisiran and givosiran are the U.S. Food and Drug Administration (FDA) approved, the first and second RNA interference- (RNAi-) based drugs indicated for the treatment of adults with polyneuropathy of hereditary transthyretin-mediated (hATTR) amyloidosis and acute hepatic porphyria (AHP), respectively [152, 153].