FDA Approves First ‘Near-Complete’ Stabilizer to Treat ATTR Cardiomyopathy

Acoramidis (Attruby; BridgeBio), a drug that stabilizes transthyretin and has demonstrated benefit on cardiovascular outcomes, has been approved by the US Food and Drug Administration for the treatment of adults with transthyretin amyloid cardiomyopathy (ATTR-CM).

The approval, announced late Friday, is based on the results of the ATTRibute-CM trial, as reported by TCTMD. In announcing the approval, BridgeBio said it has committed to providing the drug free for life to the patients who took part in the trial.

How other patients will pay for the drug is unclear: the price of the only other drug for ATTR-CM, tafamidis (Vyndaqel and Vyndamax; Pfizer), drew condemnation when it was first approved in 2019 and listed at a price of $268,000 per year. Acoramidis is already on the radar of drug price watchdogs and will be priced at about $244,000 per year.

Tafamidis, which also acts as a stabilizer of TTR, was approved on the basis of the ATTR-ACT study.

A recent report from the Institute for Clinical and Economic Review (ICER) concluded that as a class, transthyretin-stabilizing agents should each cost $13,600 to $39,000 per year to meet cost-effectiveness criteria, which means cutting the list price by 85-95%.

The 632-patient ATTRibute-CM study found that those who took oral acoramidis 800 mg twice daily had improvements in the hierarchical primary composite endpoint of all-cause mortality, cardiovascular hospitalizations, change from baseline in NT-proBNP, and change from baseline in 6-minute walk distance at 30 months compared with those randomized to placebo.

Overall, survival and cardiovascular hospitalization rates approached those of age-matched populations without ATTR cardiomyopathy, the investigators reported when they presented the results at the European Society of Cardiology Congress last year.

According to BridgeBio, acoramidis mimics a naturally occurring rescue mutation of the TTR gene that targets the root cause of ATTR-CM—destabilization of the native TTR tetramer. In the approval announcement, the company said the drug achieves “near-complete TTR stabilization.”

The company said it will now pursue approval of acoramidis in Europe, Japan, and Brazil.

A third agent in this space also has been making headlines. Earlier this month at the American Heart Association 2024 Scientific Sessions, investigators presented promising phase I results for nexiguran ziclumeran (nex-z; Intellia Therapeutics), a gene-editing therapy based on CRISPR-Cas9 that targets inactivation of the TTR gene, slowing disease progression in patients with ATTR-CM.