Shifting ATTR-CM Treatment Dynamics
What is driving Attruby™’s strong uptake?
Attruby™’s uptake continues to exceed forecasts, reinforcing its momentum and signaling a larger shift in ATTR-CM treatment dynamics – https://endpts.com/bridgebios-heart-disease-drug-Attruby™-sails-past-prescription-estimates/.
What’s Driving Attruby™’s Unexpected Uptake?
Although BridgeBio has yet to break down prescription numbers by patient type, several physicians I spoke with pointed to shifting formulary dynamics as one potential driver of Attruby™’s accelerated uptake.
Many insurers are now favoring VYNDAQUEL® (4-pill regimen) over VYNDAMAX® (single-pill regimen), forcing some patients to switch therapies unexpectedly. Payer data shows that Medicare Part D plans are dropping VYNDAMAX® in 2025, while keeping VYNDAQUEL® covered (2025-Medicare-Changes-Factsheet.pdf. Pfizer has begun sending notices during open enrollment that one or both tafamidis products may be dropped in 2025 (FINAL_VYNDAMAX®_VYNDAQUEL®_Formulary-Statement-for-Advocacy-Websites.pdf).
A cardiologist at an academic tertiary care center I spoke with confirmed this trend, noting that many patients on VYNDAMAX® for years are now facing denials on refills as insurers transition them to VYNDAQUEL®. With insurers shifting away from VYNDAMAX®'s once-daily pill, its key convenience edge is disappearing—narrowing the gap between stabilizers and making Attruby™ a more compelling alternative (Figure 1.0).
Additionally, payer policies for Attruby™ mirror those for VYNDAMAX® and VYNDAQUEL® (For example, Amyloid Cardiomyopathy), requiring prior authorization with similar medical necessity criteria. The key difference lies in BridgeBio’s aggressive approach to overcoming PA and affordability barriers, offering immediate free access (up to 30 days) for new starts through its QuickStart program (ForgingBridges™ Financial Support Form - Download It Now), while Pfizer’s VyndaCare lacks a comparable free first-month supply. While this doesn’t speed up insurance approvals, it effectively bypasses delays, ensuring patients can start therapy immediately. With no major clinical differentiation, ease of access is becoming a key prescribing driver, especially for treatment-naïve patients starting a stabilizer.
What’s Next for ATTR-CM?
Formulary dynamics may be contributing to Attruby™’s early success, but they are just one factor in a rapidly evolving ATTR-CM landscape. In the near term, Vutrisiran’s anticipated approval (PDUFA – March 23, 2025) will introduce the first silencer class, while the upcoming LOE for VYNDAMAX® and VYNDAQUEL® (as early as 2028) is expected to reshape the treatment paradigm, potentially expanding access to combination regimens.
Looking ahead, a few notable questions I have include:
Is uptake being driven by treatment switching, or is overall market growth accelerating as diagnosis rates improve? How will this impact future treatment sequencing and patient identification?
How will silencers reshape the treatment paradigm? Will they remain an option for stabilizer progressors, or will they see broader first-line use?
Where does a one-time gene editor (Nex-Z) fit? Could permanent TTR silencing shift the paradigm, or will long-term safety and durability concerns restrict its role?
What role will combination therapy play? Will stabilizer-silencer regimens emerge post- VYNDAMAX® and VYNDAQUEL® LOE, and how will payers respond?
Is there room for another class? Can depleters (ALXN2220, Coramitug) establish a meaningful role? What level of amyloid clearance will be necessary to drive meaningful?
With novel class entrants, LOE shifts, and payer-driven dynamics, ATTR-CM is at a major inflection point. How do you see these forces shaping the market? Let’s discuss.