Company: AZN
Filing Date: 2025-02-26
Form Type: 6-K
Source: 0001654954-25-001920
Chunk: 1

Company: ASTRAZENECA PLC
Filing Date: 2025-02-26
Form: 6-K
Chunk 1
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 abemaciclib) demonstrated a highly statistically significant and clinically meaningful improvement in the primary endpoint of progression-free survival (PFS). The trial evaluatedswitching to the camizestrant combinationversus continuing standard-of-care treatment with an aromatase inhibitor (AI) (anastrozole or letrozole) in combination with a CDK4/6 inhibitor in the 1st-line treatment of patients withhormone receptor ( HR)-positive, HER2-negative advanced breast cancer whose tumours have an emergent ESR1 mutation.

The key secondary endpoints of time to second disease progression (PFS2) and overall survival (OS) were immature at the time of this interim analysis. However, the camizestrant combination demonstrated a trend toward improvement in PFS2. The trial will continue as planned to further assess key secondary endpoints.

SERENA-6 is the first global, double-blind, registrational Phase III trial to use a circulating tumour DNA (ctDNA)-guided approach to detect the emergence of endocrine resistance and inform a switch in therapy before disease progression. The novel trial design used ctDNA monitoring at the time of routine tumour scan visits to identify patients for early signs of endocrine resistance and the emergence of ESR1mutations. Following detection of an ESR1mutation without disease progression, the endocrine therapy of patients was switched to camizestrant from ongoing treatment with an AI, while continuing combination with the same CDK4/6 inhibitor.

François-Clément Bidard, MD, PhD, Professor of Medical Oncology at Institut Curie & UVSQ/Université Paris-Saclay, France, and co-principal investigator for the trial, said: "Patients have an urgent need for new treatments that delay disease progression on 1st-line endocrine-based therapies. The results from SERENA-6 show that switching from an aromatase inhibitor to camizestrant in combination withany of the three CDK4/6 inhibitorsafter emergence of an ESR1 mutation delays progression of disease and extends the benefit of 1st-line treatment, representing an important step forward for patients, and a potential shift in clinical practice."

Susan Galbraith, Executive Vice President, Oncology Haematology R&D, AstraZeneca , said: "These impressive results demonstrate the versatility of camizestrant in combination with all the widely approved CDK4/6 inhibitors to provide a well-tolerated new potential treatment option in the first-line setting for the one