Switching to camizestrant at ESR1 mutation emergence before disease progression during first-line treatment of hormone receptor-positive advanced breast cancer (SERENA-6): extended analysis of a double-blind, placebo-controlled, randomised, phase 3 trial.
Blood tests detecting treatment-resistant cancer mutations allowed doctors to switch therapy early, nearly doubling progression-free survival in advanced breast cancer patients.
SERENA-6 is the first global registrational trial to use prospective ctDNA monitoring (ESR1 mutation detection) to preemptively switch endocrine therapy before clinical progression in HR+/HER2-negative advanced breast cancer; 315 patients switching to camizestrant experienced nearly double the progression-free survival versus those continuing aromatase inhibitor. The significant improvement in second progression-free survival further validates ctDNA-guided early treatment switching as an immediately actionable clinical strategy.
What the study was
- Study design
- Phase 3 randomized double-blind placebo-controlled trial
- Population
- Adults with HR+/HER2-negative advanced breast cancer receiving first-line AI+CDK4/6i with emergent ESR1 ctDNA mutation (n=315)
- Sample size
- 315
- Category
- Treatment Innovation
- Maturity
- Potentially Practice-Changing
- Journal
- The Lancet. Oncology
Why it surfaced
First registrational phase 3 RCT validating ctDNA-guided preemptive therapy switching before clinical progression; statistically significant PFS and PFS2 benefits with manageable toxicity render this immediately practice-changing for HR+ advanced breast cancer management.
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