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Getting the latest healthcare news for you
Getting the latest healthcare news for you
The FDA has granted accelerated approval to camizestrant (Etcamah) combined with a CDK4/6 inhibitor for HR-positive, HER2-negative advanced breast cancer patients who develop an ESR1 mutation during treatment. Based on the phase 3 SERENA-6 trial, switching to camizestrant upon mutation detection — before disease progression — cut the risk of progression or death by 56%. It's also the first FDA approval of a cancer treatment change based on a ctDNA test rather than imaging.
The FDA has granted accelerated approval to camizestrant (Etcamah, AstraZeneca) in combination with a CDK4/6 inhibitor (abemaciclib, palbociclib, or ribociclib) for adults with hormone receptor-positive, HER2-negative locally advanced or metastatic breast cancer who develop an ESR1 mutation during aromatase inhibitor (AI) and CDK4/6 inhibitor therapy. The approval marks a historic first: it's the first time the FDA has authorized a change in cancer treatment based on circulating tumor DNA (ctDNA) testing — specifically the Guardant360 CDx assay — rather than waiting for radiographic evidence of disease progression.
The decision was backed by the phase 3 SERENA-6 trial, which enrolled 315 patients with detectable ESR1 mutations. Switching to camizestrant early — before clinical progression — dramatically outperformed continuing the AI, with a median PFS of 16 months vs. 9.2 months. Quality-of-life deterioration was also significantly delayed (21 months vs. 6.4 months). Overall survival data remain immature, and confirmatory studies are required.
By the Numbers
Why it matters: ESR1 mutations are a leading driver of resistance to standard endocrine therapy in advanced breast cancer. This approval empowers oncologists to act earlier — swapping therapy at the molecular signal rather than waiting for visible disease progression — potentially preserving quality of life and extending the time before cancer worsens.
