37 Estimating the Direct and Indirect Resource Burden of Treatment Management With Current Standard of Care or Elacestrant for ER+, HER2–, ESR1-Mutated Advanced or Metastatic Breast Cancer Patients: A Population- Level Provider Model

37 Estimating the Direct and Indirect Resource Burden of Treatment Management With Current Standard of Care or Elacestrant for ER+, HER2–, ESR1-Mutated Advanced or Metastatic Breast Cancer Patients: A Population- Level Provider Model

Background

Breast cancer continues to have a large impact on the global burden in terms of morbidity and health care resource utilization (HRU). Endocrine therapy (ET) plus CDK4/6 inhibitor is the mainstay for the management of estrogen receptor-positive (ER+)/HER2- negative (HER2–) metastatic breast cancer (mBC) as first-line therapy; however, tumors eventually develop resistance to ET. ESR1 mutations represent a type of acquired resistance in up to 40% of patients that predominantly occurs after ET, particularly aromatase inhibitors, reducing the efficacy of available regimens. In the phase 3 EMERALD study, elacestrant was associated with significantly prolonged progression-free survival (PFS) and a manageable safety profile vs standard of care (SOC) ET in patients with ER+/HER2–, ESR1 mutations advanced mBC, leading to the first oral selective estrogen receptor degrader (SERD) being approved. Patients receiving elacestrant demonstrated a median PFS of 3.8 months vs 1.9 months with SOC ET (Bidard, 2022). Patients who received at least 12 months of prior CDK4/6 inhibitors experienced a PFS of 8.6 months with elacestrant vs
1.9 months with SOC ET. Understanding the resource implications of elacestrant as a novel treatment strategy is essential for health care decision-makers, providers, and patients.

Methods

A decision analytic model estimated the clinical events and HRU offsets resulting from treating patients with elacestrant over a 3-year time horizon. This analysis estimated the average number of patients with disease progression following at least 1 line of ET treated at a facility each year. Outcomes included the number of deaths, adverse effects (AEs), hospital days due to AEs, fulvestrant administration, outpatient visits, inpatient visits, emergency department (ED) visits, and lost hours avoided, including the number of patients requiring subsequent treatment. The model analyzed a scenario in which the current treatment mix of eligible patients converted to elacestrant.

Results

Among about 500 patients with breast cancer per facility, 21 patients were estimated to be eligible for treatment each year, totaling 64 patients over the modeled time horizon. Elacestrant led to a reduction in the number of clinical events, with 1 death and 27 grade 3 or higher AEs avoided. Reductions in HRU were observed with 131 fewer hospital days; 791 fewer fulvestrant administrations; and a reduction in 1449 outpatient, 215 inpatient, and 55 ED visits. The number of hours of missed work avoided and activity impairment avoided were estimated to be 5853 hours and 6082 hours, respectively.

Conclusions

This decision analytic model demonstrated that treating patients with elacestrant resulted in a meaningful reduction in the number of clinical and health care resource utilization events while showing improvements in work productivity and activities of daily living.