Novel therapy for ESR1-mutated advanced or metastatic breast cancer approved by FDA

February 2023 Pharma News Willem van Altena

The Food and Drug Administration (FDA) in the USA has announced the approval of elacestrant for postmenopausal women or adult men with ER-positive, HER2-negative, ESR1-mutated advanced or metastatic breast cancer with disease progression following at least one line of endocrine therapy. Elacestrant is an oral selective oestrogen receptor degrader (SERD) that was already granted priority review in 2022. The drug is marketed by Stemline Therapeutics with the brand name Orserdu.

The FDA approval follows on positive findings from the phase III EMERALD study, which showed that elacestrant significantly improved progression-free survival (PFS) versus standard-of-care endocrine monotherapy in both the overall population and in ESR1-mutation carriers. Results demonstrated that in patients with ESR1 mutations, median PFS was 3.8 months for elacestrant and 1.9 months in the fulvestrant or aromatase inhibitor arm.

Meanwhile, an exploratory analysis of PFS in patients without ESR1 mutations showed a hazard ratio of 0.86 for PFS, indicating that the significant benefit seen in the overall population was primarily driven by the ESR1-mutated subgroup, according to the FDA.

Following the FDA-approval of elacestrant, being the first ever therapy for ER+, HER2- advanced or metastatic breast cancer patients with ESR1 mutations, it is expected that the European Medicines Agency will reach a decision later this year. Elacestrant is currently under review with the EMA.

Reference

Press release by the FDA regarding approval of elacestrant (27 January 2023)