AstraZeneca PLCCamizestrant failed to meet the primary endpoint in Phase III SERENA-4, a setback to a key oncology growth opportunity.

AstraZeneca's breast cancer pill Etcamah, also known as camizestrant, failed to meet the primary endpoint in the Phase III SERENA-4 trial, a setback to one of the company's key oncology growth opportunities. The trial tested Etcamah plus Pfizer's Ibrance, or palbociclib, in 1,371 previously untreated patients with ER-positive, HER2-negative advanced breast cancer and found a numerical improvement in progression-free survival that was not statistically significant. AstraZeneca had estimated camizestrant could eventually generate more than $5 billion in annual sales, and its U.S.-listed shares fell about 3% in after-hours trading after the announcement. The failure removes some potential expansion into a broader first-line population, but the drug retains an approved franchise in the narrower ESR1-mutated setting, where the Phase III SERENA-6 trial showed a 55% reduction in the risk of disease progression or death and median progression-free survival of 16.8 months versus 9.2 months for standard therapy, supporting U.S. accelerated approval in September 2026 and EU approval in July. AstraZeneca reported first-half 2026 revenue up 6% at constant exchange rates with double-digit growth in Oncology and Rare Disease, and said it remains on track toward its ambition of $80 billion in total revenue by 2030.
AstraZeneca PLCCamizestrant failed to meet the primary endpoint in Phase III SERENA-4, a setback to a key oncology growth opportunity.
Pfizer Inc