A Phase 3 setback for AstraZeneca and Ionis’ eplontersen (Wainua) is taking center stage as investors and cardiology stakeholders parse why the trial missed its primary objective—against the backdrop of ongoing scrutiny of RNA-targeting “silencer” medicines in transthyretin cardiac amyloidosis (ATTR-CM). At ESC 2026, the companies faced renewed pressure after data were presented and interpreted alongside competing perspectives on trial conduct. The reporting highlights that the failure narrative has become entangled with treatment background effects, including whether concurrent therapies influenced outcomes. Separate coverage frames Alnylam’s RNA program as being closely watched for signals that could feed into market confidence for the broader class. The immediate implication is tighter clinical and scientific scrutiny on incremental benefit, endpoint selection, and real-world use of RNA therapies in cardiomyopathy populations.