March 25, 2025 – The FDA has approved a new treatment for adults with a life-threatening heart condition called transthyretin amyloid cardiomyopathy (ATTR-CM).
ATTR-CM is a rare but serious heart condition that can be inherited or come with age. It happens when unstable transthyretin (TTR) proteins form amyloid deposits in the heart, causing the heart muscles to become thick and stiff. This makes it harder for the heart to pump blood, leading to breathlessness, fatigue, fainting, irregular heart rhythms, heart failure, and an increased risk of early death.
Sold under the name Amvuttra, this new treatment works in a unique way to quickly lower transthyretin levels, tackling the disease at its root. It helps lower the risk of heart-related deaths, reduces hospital stays, and cuts down on emergency heart visits. Amvuttra contains vutrisiran, a medicine that uses RNA interference (RNAi) to stop the gene that makes faulty TTR protein. This helps slow heart damage caused by harmful protein buildup.
Amvuttra was first approved in 2022 for nerve damage from TTR buildup. A doctor gives it as an injection under the skin four times a year.
"Despite recent advances, there remains a significant need for patients living with ATTR-CM, and I’ve witnessed, firsthand, the impact that ATTR amyloidosis can have on families, including diminished quality of life and the loss of loved ones," Muriel Finkel, president of the Amyloidosis Support Groups, said in a news release by Alnylam, the maker of Amvuttra. "The availability of this groundbreaking treatment option is a significant moment for patients living with ATTR amyloidosis. It represents a beacon of hope for our community."
The FDA approval is based on a clinical trial involving 655 people with ATTR-CM. The results showed that Amvuttra reduced the risk of death and repeat heart-related events by 28% over 36 months. In a follow-up period extending to 42 months, the risk of death was reduced by 36%.
Common side effects of Amvuttra include limb and joint pain, shortness of breath, and low vitamin A levels. While no new safety concerns were found, patients should take the recommended daily vitamin A and see an eye doctor if they have vision issues like night blindness.
Alnylam stated that it partners with insurers to ensure broad access to the drug and offers patient support, including help with treatment, insurance, finances, and education.
