About the Oncotype DX AR-V7 Nucleus Detect Test
The Oncotype DX AR-V7 Nucleus Detect test is designed to help you more effectively guide treatment for patients with metastatic castration-resistant prostate cancer (mCRPC). Analytically and clinically validated, AR-V7 Nucleus Detect determines if the patient has circulating tumor cells that are AR-V7 positive, and therefore; resistant to androgen receptor signaling inhibitor (ARSI) treatments, such as Zytiga® (abiraterone) or Xtandi® (enzalutamide). As a result, you can more confidently choose whether to order additional ARSI treatments or taxane chemotherapy treatment for your patients.
Genomic Health, Inc. and Epic Sciences, Inc. have entered into an exclusive agreement to commercialize Epic Sciences' novel AR-V7 liquid biopsy test in the United States through Genomic Health's world-class oncology and urology sales and medical liaison teams. Using Epic Sciences’ No Cell Left Behind technology, this blood-based test detects the V7 variant of the androgen receptor protein (AR-V7) in the nucleus of circulating tumor cells (CTC) – and provides information that may help guide treatment selection in patients with metastatic castration-resistant prostate cancer (mCRPC).
AR-V7 Nucleus Detect helps remove the uncertainty from mCRPC treatment, accurately identifying patients likely to fail ARSI treatment and clarifying the need to transition them to chemotherapy.
How AR-V7 Nucleus Detect works
The AR-V7 Nucleus Detect assay is the only mCRPC test that identifies patients with AR-V7 protein in the nucleus —providing essential context to optimize physician's treatment of men with mCRPC. A liquid biopsy, the AR-V7 Nucleus Detect assay analyzes circulating tumor cells (CTCs) in the patient’s blood. The sample is obtained through a simple blood draw. No intrusive or expensive procedures are required.
Why AR-V7 Nucleus Detect is a Critical Diagnostic Tool
Although ARSI treatments—such as Zytiga and Xtandi —are a breakthrough in the treatment of mCRPC, a significant number of patients fail to respond to second or third+ lines of ARSI. In many cases, this failure is because tumors adapt (and become resistant) to ARSI treatment..
One of the most common adaptations is the V7 variant of the androgen receptor protein (AR-V7). Studies show that patients with AR-V7 in the nucleus of circulating tumor cells do not benefit from ARSi treatments, with rapid disease progression and low median survival. While patients with AR-V7 CTCs are resistant to ARSi treatments, they can respond to taxane chemotherapy. As a result, detection of nuclear AR-V7 is an urgent indication that supports sequencing patients to taxane chemotherapy instead of more lines of ARSI treatments.
AR-V7 Nucleus Detect:
- Is predictive of non-response to ARSI therapy when AR-V7 positive CTCs are detected
- Minimizes false positives by targeting only nuclear AR-V7 proteins (the active species), not cytoplasmic AR-V7 proteins
Oncotype DX AR-V7 Nucleus Detect is the only predictive and prognostic test for patients with metastatic castration-resistant prostate cancer (mCRPC). See the competitive comparisons and clinical study summaries below to find out how AR-V7 Nucleus Detect can benefit patients and streamline your treatment planning process.
- Study 1 findings: Nuclear AR-V7 presence predicts chemotherapy benefit1: A 2016 study published in JAMA Oncology from Memorial Sloan Kettering Cancer Center demonstrated that mCRPC patients with the V7 variant of the androgen receptor protein (AR-V7) in the nuclei of circulating tumor cells (CTCs) had significantly better clinical outcomes when treated with taxane chemotherapy. Patients with nuclear AR-V7+ CTCs had a 76% reduction of risk of death when treated with chemotherapy. This suggests that patients with AR-V7 positive CTCs should consider life-prolonging chemotherapy as an alternative to potentially less effective and more expensive hormonal treatment with ARSI drugs. These study results underscore the potential for an AR-V7 predictive test to allow advanced prostate cancer patients to avoid ineffective therapies and to receive chemotherapy at an earlier stage when it may be more beneficial.
- Study 2 findings: Nuclear-specific localization is required for accurate test results2: A 2016 study published in European Urology analyzed outcomes for patients with mCRPC on ARSI and standard chemotherapy. The authors found that: Patients with CTCs that had AR-V7 protein in the cellular nuclei were very likely to survive longer on taxane-based chemotherapy. Additionally, the study found that nuclear-specific localization is required to reliably inform treatment selection using an AR-V7 protein biomarker in CTCs.