Elacestrant in hormone receptor-positive metastatic breast cancer: a post-hoc analysis

Breast cancer is a leading cause of mortality in women. Hormone therapy plays a crucial role in treatment of hormone receptor-positive metastatic breast cancer. Elacestrant is a selective estrogen receptor degrader (SERD) that has shown promise in early-phase clinical trials. This post-hoc analysis systematically evaluates elacestrant's effectiveness in hormone receptor-positive metastatic breast cancer patients, providing insights into its efficacy, safety, and potential advantages over existing treatments.

We adhered to the PRISMA Statement 2020 guidelines and systematically searched the databases PubMed/MEDLINE, ClinicalTrials.gov, Web of Science, and Embase. We conducted the post-hoc analysis using R software (V 4.3.3), applying the inverse variance method and the DerSimonian-Laird estimator to pool effect estimates with a random-effects model. We assessed heterogeneity using the Cochran's Q test and the I ² statistic.

Our post-hoc analysis encompassed 3 clinical trials and a total of 835 participants. The mean age of all 835 participants across the three trials was 59.5 years (95% CI: 58.7-60.3). The pooled progression-free survival (PFS)-was estimated at 4.38 (95% CI: -7.58-16.35, P = 0.47), and the pooled objective response rate (ORR) was 7% (95% CI: 2-18%, P = 0.04), with significant heterogeneity observed among the studies.

Elacestrant shows promise for improving outcomes in hormone receptor-positive metastatic breast cancer, but further research is needed to confirm its effectiveness. Future studies should include larger sample sizes, comprehensive phase II and III trials, and investigation of elacestrant in combination with other drugs or in preoperative settings.