Atrium Therapeutics spun out of Avidity Biosciences with a $270 million launch financing to advance RNA‑based therapeutic candidates for rare inherited cardiomyopathies. The new company inherits programs and know‑how tied to RNA‑directed modalities and has prioritized two lead candidates with plans toward clinic entry in disorders that currently lack FDA‑approved options. Investors backing the spinout signal continued appetite for RNA platforms focused on genetically defined cardiovascular indications.