Validated in a large clinical cohort, Oncotype DX AR-V7 Nucleus Detect is the only test proven to detect resistance to androgen receptor targeted therapies (such as abiraterone and enzalutamide) in patients with metastatic castration-resistant prostate cancer (mCRPC).
Clinical studies found that AR-V7+ patients do not benefit from AR-targeted therapies
AR-V7 Nucleus Detect is designed to detect AR-V7 proteins in the nucleus of circulating tumor cells (CTCs). Large clinical studies found that AR-V7+ patients (patients with AR-V7 in the nucleus of CTCs):
- Do not benefit from AR-targeted therapies.
- Experience faster progression and lower median overall survival (compared with patients negative for AR-V7).
- Are substantially more likely to live longer when treated with taxane chemotherapy.1, 2
Study 1: Nuclear AR-V7 presence predicts lack of effectiveness of AR-targeted therapies1
A study published in JAMA Oncology from Memorial Sloan Kettering Cancer Center demonstrated that mCRPC patients with AR-V7+ CTCs had a 76% reduction of risk of death when treated with chemotherapy. This suggests that patients with detectable blood levels of AR-V7 should consider life-prolonging chemotherapy as an alternative to potentially less effective and more expensive hormonal treatment with AR-targeted therapies.
In the chart below, note that all patients who were nuclear AR-V7+ and treated with an AR-targeted therapy died within 12 months, underscoring lack of efficacy of AR-targeted therapies in this patient population.
AR-V7+ patients treated with AR-targeted therapies had significantly reduced overall survival2*
Study 2: Nuclear-specific localization is required for accurate test results2
A 2016 study published in European Urology analyzed outcomes for patients with mCRPC on AR-targeted therapies and standard chemotherapy. The authors found that patients with nuclear AR-V7 in CTCs were very likely to survive longer on taxane-based chemotherapy, whereas location agnostic AR-V7 expression was less prognostic and not predictive.