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Breast cancer

PADA-1 trial: ESR1 mutations in plasma ctDNA guide treatment switching

PADA-1 is the first trial to demonstrate benefit from a treatment-switching strategy guided by active monitoring of ESR1 mutations in plasma circulating tumour DNA (ctDNA) from patients with breast cancer. The results of this trial raise important questions about the specific treatment approach tested, and the feasibility of trials incorporating longitudinal ctDNA analyses to anticipate resistance and guide treatment.

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B.O’L. acknowledges institutional funding from the UK National Institute for Health Research to the Royal Marsden and the Institute of Cancer Research Biomedical Research Centre.

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Correspondence to Ben O’Leary.

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B.O’L. has received institutional research funding through the Institute of Cancer Research from Pfizer and has been a consultant to Merck Serono.

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O’Leary, B. PADA-1 trial: ESR1 mutations in plasma ctDNA guide treatment switching. Nat Rev Clin Oncol 20, 67–68 (2023).

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