EU Starts Review of First-Line Enhertu for Breast Cancer

Why It Matters

It introduces the first new first‑line HER2 therapy in over a decade, potentially reshaping treatment pathways and delivering substantial revenue growth for both partners.

Key Takeaways

• EMA reviewing Enhertu+pertuzumab first‑line indication.
• DESTINY‑Breast09 cut recurrence risk 44% vs THP.
• US approval positions Europe for $5 bn sales target.
• Potential expansion to neoadjuvant/adjuvant settings.
• HER2‑positive metastatic cases 15‑20% of breast cancer.

Pulse Analysis

The HER2‑positive subset of breast cancer, representing roughly 15‑20% of advanced cases, has long relied on the trastuzumab‑pertuzumab‑taxane trio as the frontline standard. While this regimen extended survival, most patients progress within two years, and one in three fail to receive subsequent therapy. This therapeutic gap has driven intense research into antibody‑drug conjugates (ADCs) that can deliver cytotoxic payloads directly to cancer cells, promising deeper and more durable responses.

Enhertu, an ADC linking trastuzumab to a topoisomerase I inhibitor, has already become a blockbuster in later‑line settings, generating $3.58 billion in H1 2026 revenue. The DESTINY‑Breast09 study’s 44% risk reduction versus THP provides compelling evidence for moving the drug earlier in the treatment algorithm. With the FDA’s recent first‑line approval, the EMA’s parallel review signals a coordinated global rollout that could accelerate the drug’s path to a $5 billion annual brand, bolstering AstraZeneca’s strategic aim of surpassing $80 billion in sales by 2030.

Beyond the immediate first‑line indication, ongoing trials (DESTINY‑Breast11 and DESTINY‑Breast05) are evaluating Enhertu in neoadjuvant and adjuvant contexts, potentially expanding its use to earlier disease stages. If successful, these studies could further differentiate the product from competing HER2 therapies and solidify its position across the breast‑cancer treatment continuum. For investors and industry observers, the EMA review underscores a pivotal moment where clinical innovation aligns with significant commercial upside, reshaping the competitive dynamics of HER2‑targeted oncology.