The Menarini Group (“Menarini”), a leading international pharmaceutical and diagnostics company, and Stemline Therapeutics, Inc. (“Stemline”), a wholly-owned subsidiary of the Menarini Group, focused on bringing transformational oncology treatments to cancer patients, presented results from phase 1b/2 ELEVATE and ELECTRA clinical studies evaluating ORSERDU® (elacestrant) in combination with other treatments. Both the ELEVATE and ELECTRA studies were designed with the objective to overcome different resistance mechanisms and enhance patient outcomes with combination treatment options. Data was presented at the 2023 San Antonio Breast Cancer Symposium (SABCS), December 5-9, 2023.
The ELEVATE study is evaluating elacestrant in combination with inhibitors of the PI3K/AKT/mTOR pathway (everolimus and alpelisib) and cell-cycle pathway inhibitors (palbociclib, ribociclib, and abemaciclib). Results reported at SABCS 2023 include all combination data from Cohort 1 of the phase 1b portion of the study, with the therapies showing predictable safety profiles that were consistent with prior studies. Additional cohorts are currently under evaluation to assess pharmacokinetics (PK) and determine the recommended phase 2 dose (RP2D) for each combination. The full abstract (1576517) can be viewed here.
“It is encouraging to see positive initial safety results in various combination studies of ORSERDU, along with promising preliminary efficacy data in these trials,” said Hope Rugo, MD, professor of medicine, Division of Hematology and Oncology at the University of California San Francisco Helen Diller Family Comprehensive Cancer Center. “We look forward to learning more about ORSERDU’s role in combination settings and its potential across the spectrum of metastatic breast cancer.”
The ELECTRA study is evaluating elacestrant in combination with abemaciclib. Phase 1b of this study will also determine the recommended phase 2 dose (RP2D) of this combination in patients regardless of metastases sites. Phase 2 will evaluate the benefit of the combination in patients with ER+/HER2- advanced or metastatic breast cancer with brain metastases since both compounds have demonstrated the ability to cross the blood-brain barrier. Results reported at SABCS 2023 include the three dose cohorts of the phase 1b portion of the study, showing a tolerable and manageable safety profile with favorable preliminary efficacy in these patients, regardless of the site of their metastases. The three cohorts have been completed with no patients experiencing dose limiting toxicities. No discontinuations have been observed for any patient beyond the observation period due to toxicity. Most common adverse events were diarrhea, nausea, and neutropenia/neutrophil count decreased. Only neutropenia was associated with grade 3 events with the combination; managed with standard dose reduction for abemaciclib. The full abstract (1576518) can be viewed here.
“People living with ER+ metastatic breast cancer are often faced with treatment resistance, causing a significant need for innovative new options,” said Elcin Barker Ergun, CEO of the Menarini Group. “While this data is preliminary, we are committed to advancing our comprehensive research on ORSERDU in combination with other treatments, to potentially help enhance patient outcomes, with the goal of extending and improving the lives of people with this disease.”
See here for details of the Menarini Group/Stemline Therapeutics’ full range of presentations at SABCS.
About The Elacestrant Clinical Development Program
Elacestrant is also being investigated in several clinical trials in metastatic breast cancer disease, alone or in combination with other therapies. ELEVATE (NCT05563220) is a phase 1b/2 clinical trial that will evaluate the safety and efficacy of elacestrant combined with alpelisib, everolimus, palbociclib, abemaciclib, and ribociclib. ELECTRA (NCT05386108) is an open-label phase 1b/2, multicenter study evaluating elacestrant in combination with abemaciclib in patients with ER+, HER2- breast cancer. The phase 2 portion evaluates this treatment regimen in these patients with brain metastases. ELCIN (NCT05596409) is a phase 2 trial evaluating the efficacy of elacestrant in patients with estrogen receptor positive (ER+), human epidermal growth factor receptor-2 negative (HER2-) advanced/metastatic breast cancer who received one or two prior hormonal therapies and no prior cyclin-dependent kinase targeting enzymes CDK4 and CDK6 inhibitor (CDK4/6i) in the metastatic setting. Elacestrant is also being evaluated in early breast cancer disease.
About ORSERDU (elacestrant)
U.S. Indication: ORSERDU (elacestrant), 345 mg tablets, is indicated for the treatment of postmenopausal women or adult men with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, ESR1-mutated advanced or metastatic breast cancer with disease progression following at least one line of endocrine therapy.
Full prescribing information for the U.S. can be found at www.orserdu.com.