The FDA has granted approval to BridgeBio Pharma's Attruby (acoramidis) for the treatment of transthyretin amyloid cardiomyopathy (ATTR-CM), a progressive and often fatal heart condition. This approval marks a significant advancement in the treatment landscape for ATTR-CM, offering a new therapeutic option for patients.
Attruby, an orally administered drug, is designed to stabilize the misfolded transthyretin (TTR) protein, preventing its accumulation in the heart tissue. The approval was based on clinical trial data demonstrating that Attruby significantly reduced cardiovascular death and cardiovascular-related hospitalizations compared to placebo. Patients treated with Attruby also experienced improvements in quality of life and markers of heart health.
Clinical Efficacy
In clinical trials, Attruby demonstrated a statistically significant benefit in reducing the combined endpoint of all-cause mortality and cardiovascular hospitalization. The treatment effect was observed as early as three months, with a greater magnitude of action compared to existing therapies, according to BridgeBio's CEO, Neil Kumar. While direct comparisons between Attruby and other treatments like tafamidis are limited due to the absence of head-to-head trials, Kumar suggests that Attruby may be a more potent option for certain patients.
Market Dynamics and Competition
The approval of Attruby sets the stage for increased competition in the ATTR-CM market, which has been primarily dominated by Pfizer's tafamidis (Vyndaqel). Global Market Insights estimates the overall market for transthyretin amyloidosis treatments will surpass $11 billion by 2032, with the cardiomyopathy form accounting for the bulk of drug sales. BridgeBio has priced Attruby at just under $19,000 for a 28-day supply, translating to an annual list cost of approximately $244,000.
Despite the promising clinical data, Wall Street analysts have expressed some skepticism about BridgeBio's ability to capture a significant market share, given Pfizer's established presence and the potential entry of Alnylam Pharmaceuticals' vutrisiran into the market. However, BridgeBio remains optimistic, with plans to conduct a head-to-head trial against tafamidis to further differentiate Attruby and demonstrate its clinical advantages.
Addressing Unmet Needs
Transthyretin amyloidosis affects an estimated 250,000 to 300,000 people in the U.S., many of whom remain undiagnosed. ATTR-CM is caused by the misfolding and aggregation of the TTR protein, leading to heart failure and death. Until recently, diagnosis was often delayed until patients had advanced heart failure. The availability of new treatments like Attruby and increased awareness of the disease are expected to improve patient outcomes.
Future Outlook
BridgeBio anticipates competing with Pfizer for newly diagnosed patients and aims to secure a market share of approximately 30%. The company's CEO acknowledges the challenges of launching a new drug in a competitive market but expresses confidence in Attruby's potential to address the unmet needs of patients with ATTR-CM. Bayer holds rights to Attruby in Europe through a collaboration, with potential approval in 2025.
