French drug major Sanofi (SNYNF,SNY) Monday said its Phase 2 AMEERA-3 clinical trial evaluating amcenestrant, an investigational optimized oral selective estrogen receptor degrader or SERD, did not meet its primary endpoint of improving progression-free survival or PFS.
Amcenestrant is an optimized oral SERD that binds to the estrogen receptors or ER in breast cancer cells to inhibit their normal function and trigger degradation so they can no longer be used by tumor cells to grow.
AMEERA-3 was an open-label, Phase 2 randomized trial. It evaluated amcenestrant as monotherapy compared to single-agent endocrine treatment of physician's choice in patients with locally advanced or metastatic estrogen receptor-positive or ER+/human epidermal growth factor receptor 2-negative or HER2- breast cancer who progressed on or after hormonal therapies.
The primary objective of AMEERA-3 was to determine whether amcenestrant improved PFS assessed by an independent central review compared to endocrine monotherapy.
In an update on the study of amcenestrant as a monotherapy in ER+/HER2- advanced or metastatic breast cancer, the company noted that no new safety signals were identified and the safety profile of amcenestrant in AMEERA-3 was consistent with earlier studies.
Sanofi said it will continue to assess data from the AMEERA-3 trial and work with investigators on the publication of the full results. The ongoing clinical trial program for amcenestrant continues as planned, including AMEERA-5 and AMEERA-6.
John Reed, Head of Research and Development at Sanofi, said, "While we are disappointed with the AMEERA-3 results, we continue to investigate amcenestrant in patients with earlier stages of breast cancer with different tumor profiles and where different standard of care treatments are used."
The company noted that amcenestrant is currently under clinical investigation and its safety and efficacy have not been evaluated by any regulatory authority.
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