Coramitug (60 mg/kg) was associated with improved functional echocardiographic parameters and was well tolerated.<h4>Conclusions</h4>This phase 2 trial showed that coramitug, an antibody targeting misfolded transthyretin in transthyretin amyloidosis with cardiomyopathy, was well tolerated and, at a dose of 60 mg/kg, resulted in a statistically significant reduction in NT-proBNP, a validated marker of disease progression, with no statistically significant effect on 6-minute walk test within 52 weeks.<h4>Registration</h4>URL: https://www.clinicaltrials.gov; Unique identifier: NCT05442047. This evidence concerns the gene NPPB and cardiomyopathy.