Overview

• The phase III Serena-6 trial enrolled over 3,200 patients with advanced hormone receptor-positive, HER2-negative breast cancer across 23 countries.
• Circulating tumor DNA tests identified ESR1 mutations as early signs of hormone therapy resistance before tumors regrew.
• Switching to camizestrant at the first sign of resistance reduced the risk of disease progression or death by 56% compared with standard therapy.
• Median progression-free survival increased from 9.2 months on standard treatment to 16 months for those receiving camizestrant.
• Camizestrant was generally well tolerated with only 1% of participants discontinuing due to side effects and awaits FDA approval.