Oral SERD camizestrant in ER+, HER2- advanced breast cancer

Results of the phase I SERENA-1 trial, recently published on Annals of Oncology, showed safety and tolerability of camizestrant, a next-generation oral selective ER antagonist and degrader (SERD) and pure ER antagonist, in ER+, HER2- advanced breast cancer patients, suggesting clinical benefits in a  heavily pretreated population.

SERENA-1 trial is a phase I, multi-part, open-label study which enrolled 108 pre- and post-menopausal women with ER+, HER2− advanced breast cancer to determine the safety and tolerability of camizestrant monotherapy and define doses for clinical evaluation. 86.1% of patients experienced treatment-related adverse event, 82.4% of which were grade 1 or 2; estimated half-life is 20-23 h. Efficacy was observed at all doses investigated, including in patients with prior CDK4/6 inhibitors and/or fulvestrant treatment, with and without baseline ESR1 mutations, and with visceral disease, including liver metastases. As authors say, «camizestrant has a well-tolerated safety profile, pharmacokinetics characteristics suitable for once-daily dosing, and evidence of pharmacodynamic and clinical efficacy in heavily pre-treated patients. The study established that the doses of interest for phase II testing were 75, 150, and 300 mg once daily. The ongoing subsequent parts of SERENA-1 aim to further investigate camizestrant in combination with other anticancer agents relevant to ER+, HER2− advanced breast cancer, including palbociclib, abemaciclib, everolimus, and capivasertib».