Two novel therapies have demonstrated significant survival improvements for patients with estrogen receptor (ER)-positive, HER2-negative advanced breast cancer—one of the most common breast cancer subtypes, representing ~70% of cases. These findings, presented at the 2025 ASCO Annual Meeting and published in The New England Journal of Medicine, highlight potential benefits for employees and their families navigating advanced disease.
Inavolisib + Palbociclib-Fulvestrant (PIK3CA-Mutated Patients)
- What it is: A triplet therapy targeting three key pathways driving ER+ breast cancer, offering the first-ever overall survival benefit for patients with PIK3CA mutations when treated in the first-line setting (~35–40% of cases).
- Key outcomes: Median overall survival of 34 months vs. 27 months (HR=0.67); progression-free survival 17.2 vs. 7.3 months; objective response rate 63% vs. 28%.
- Impact: Early clinical benefits and delayed need for chemotherapy, improving quality of life and reducing treatment burden. FDA approved in October 2024.
Employer consideration: The research suggests that this therapy could delay expensive chemotherapy regimens and their associated complications, potentially reducing the total cost of care.
Vepdegestrant (ESR1-Mutated Patients)
- What it is: The first oral PROTAC ER degrader for patients with ESR1 mutations (40–50% of ER+ cases), designed for those progressing after standard endocrine therapy plus CDK4/6 inhibitors.
- Key outcomes: Median progression-free survival of 5 months vs. 2.1 months in ESR1-mutated patients; clinical benefit rate 42% vs. 20%.
- Impact: Offers a promising new option with a differentiated safety profile for patients with limited alternatives. Received FDA Fast Track designation in February 2025.
Employer consideration: This treatment could provide an option for patients who previously had limited alternatives, plus oral administration means could reduce the number of infusion visits required.
Why it Matters for Employers
Advanced breast cancer is one of the most common cancers among commercially insured employees. Providing access to personalized treatments—such as the latest targeted therapies—can lead to:
- Better clinical outcomes for employees
- Delayed need for chemotherapy, helping preserve productivity and reduce absenteeism
- Improved overall wellbeing for those affected
- Potential cost savings for plan sponsors through fewer hospitalizations, emergency visits, and less intensive supportive care
