OPTIMA results showed that 68% of clinically high-risk patients could safely forgo chemotherapy, achieving a 5-year cancer-free survival rate of 93.7% with hormone therapy alone.

The OPTIMA clinical trial, initiated in 2007 and involving over 4,400 patients across multiple countries, evaluated whether Prosigna-guided treatment could safely spare chemotherapy in high-risk, early-stage (ER-positive, HER2-negative) breast cancer.

The trial demonstrated efficacy across diverse populations, including premenopausal women and patients with lymph node involvement, indicating the test’s broad applicability.

The test was developed by researchers including UNC geneticist Charles Perou and is marketed by Veracyte to predict whether chemotherapy is necessary or if hormone therapy alone suffices.

The trial followed 4,429 patients for a median of 4.0 years and provided Level 1A evidence that Prosigna accurately predicts chemotherapy benefit and supports safe de-escalation of treatment across diverse groups, including premenopausal women and those with lymph node involvement.

Prosigna computes a Risk of Recurrence (ROR) score from tumor analysis using machine learning to estimate long-term outcomes and recurrence risk, guiding treatment decisions for ER-positive, HER2-negative breast cancer.

Since commercialization, Prosigna is available to clinicians in the United States and United Kingdom to personalize treatment and reduce unnecessary chemotherapy while preserving outcomes.

The OPTIMA trial results were presented at the 2026 ASCO Annual Meeting in Chicago on May 30.