BridgeBio's Breakthrough: Challenging Pfizer in the Competitive ATTR-CM Market

The pharmaceutical landscape is set to witness a significant shift with the FDA's approval of BridgeBio Pharma's Attruby (acoramidis) for the treatment of transthyretin amyloid cardiomyopathy (ATTR-CM). This rare heart disease affects adults, leading to progressive heart failure and increased mortality. The approval of Attruby, an orally-administered near-complete (≥90%) stabilizer of Transthyretin (TTR), presents a formidable challenger to Pfizer's Vyndaqel (tafamidis) franchise, which dominates the ATTR-CM market.

BridgeBio's drug has demonstrated remarkable results in clinical trials, significantly reducing cardiovascular death and hospitalization. The ATTRibute-CM Phase 3 study enrolled 632 participants, randomly assigning them to receive Attruby or a placebo for 30 months. The trial successfully met its primary endpoint, with a 4-component composite endpoint Win Ratio of 1.8 (p<0.0001). Attruby also demonstrated a statistically significant treatment effect on the Kansas City Cardiomyopathy Questionnaire and 6-minute walk test, with an increase in NT-proBNP on treatment about half that of placebo.

Attruby's advantage lies in its near-complete TTR stabilization, which mimics a naturally occurring "rescue mutation" of the TTR gene (T119M). This feature sets it apart from Pfizer's partial stabilizers, Vyndaqel and Vyndamax, which reduce TTR monomers by only 60%. The superior stabilization has shown promising clinical outcomes, potentially boosting Attruby's market share in the lucrative yet competitive ATTR-CM market.

However, Pfizer's established market presence and brand recognition may pose a challenge to BridgeBio. With Vyndaqel franchise generating $3.9 billion in sales in the first nine months of 2024, Pfizer's drug maintains a strong foothold. BridgeBio must effectively communicate Attruby's advantages to healthcare providers and patients to successfully challenge Pfizer.

Pfizer's pricing strategy may also evolve in response to Attruby's entry. BridgeBio's drug is priced similarly to Pfizer's offerings, with a 28-day supply costing $18,759. Pfizer might explore discounts or rebates to retain market share or adjust its pricing to reflect Attruby's near-complete TTR stabilization.



The competitive landscape in the ATTR-CM market is dynamic, with other players such as Alnylam's Amvuttra and AstraZeneca and Ionis' eplontersen also targeting the indication. Analysts predict Attruby's peak sales could reach $2 billion or more, with Mizuho Securities estimating up to $4 billion annually. The regulatory and reimbursement landscape is promising for Attruby, with the FDA approval based on robust Phase 3 trial data.

In conclusion, the FDA approval of BridgeBio Pharma's Attruby presents a significant challenge to Pfizer's dominance in the ATTR-CM market. With its near-complete TTR stabilization and positive trial results, Attruby has the potential to capture a substantial share of this competitive market. As BridgeBio leverages its partnership with Bayer for European commercialization and maintains competitive pricing, Pfizer faces a formidable rival in the pursuit of market leadership.