AstraZeneca’s ATTR-CM Silencer Trial Fails to Show Benefit Over Existing Stabilizer Therapy

AstraZeneca announced that its Phase 3 trial of a silencer drug for transthyretin amyloid cardiomyopathy (ATTR-CM) did not meet its primary endpoints. The study showed no additional clinical benefit for patients who were already receiving a stabilizer medication.

The trial enrolled participants with progressive ATTR-CM, most of whom were on a stabilizer at baseline. Researchers found that adding the silencer to the existing therapy failed to improve outcomes, leading to the study’s termination.

The negative result impacts AstraZeneca and its development partner Ionis Pharmaceuticals, and raises concerns for other firms with similar products. Companies such as Alnylam, which markets another silencer, and BridgeBio, which offers a new stabilizer, may see market dynamics shift as analysts reassess the billion‑dollar ATTR-CM space.