On May 1, 2026, the FDA approved vepdegestrant (Veppanu) for adults with ER-positive, HER2-negative, ESR1-mutated advanced or metastatic breast cancer. At the same time, the Guardant360 CDx was approved as a companion diagnostic to detect these mutations using a simple blood test.
The approval is based on the Phase 3 VERITAC-2 trial, which compared vepdegestrant with fulvestrant in patients whose cancer had progressed after prior endocrine therapy. In patients with ESR1 mutations, vepdegestrant improved progression-free survival to 5.0 months compared with 2.1 months for fulvestrant. It also reduced the risk of disease progression or death by 43% and showed a higher response rate (19% vs. 4%).
The drug showed a manageable safety profile. Only 2.9% of patients stopped treatment بسبب side effects. Common side effects included fatigue, muscle and joint pain, nausea, and lab changes such as low white blood cells and higher liver enzymes. Serious side effects occurred in 9% of patients.
This approval highlights a move toward more personalized treatment in breast cancer. By using a blood test to detect ESR1 mutations, doctors can choose a targeted therapy that directly addresses a key mechanism driving treatment resistance.