Summary: Mercy BioAnalytics will present groundbreaking data at the American Society of Clinical Oncology Annual Meeting, showing that their Mercy Halo test significantly improves early detection of ovarian cancer compared to traditional methods.


  1. The Mercy Halo test detected 82% of high-grade serous ovarian cancer cases up to one year before diagnosis with 98% specificity in a large retrospective study.
  2. This test outperformed the CA125 serum biomarker, detecting more cancers and reducing false positives by almost half.
  3. The Mercy Halo test uses a small serum or plasma volume for qPCR-based detection of multiple cancer-related biomarkers, offering a high-performance, low-cost screening tool.

Mercy BioAnalytics, Inc., a provider of extracellular vesicle-based liquid biopsy for the early detection of cancer, says it will present data at the upcoming American Society of Clinical Oncology Annual Meeting demonstrating the first significant improvement in the early detection of ovarian cancer using a locked assay since CA125 serum biomarker testing and transvaginal ultrasound imaging were introduced nearly 40 years ago.

In a large blinded, retrospective analysis of prospectively collected samples from more than 1,300 asymptomatic postmenopausal women, the Mercy Halo test detected 82% of high grade serous ovarian cancer (HGSC) cases up to one year prior to diagnosis with 98% specificity.

UK Ovarian Cancer Trial

Mercy, in collaboration with the team at the Medical Research Council Clinical Trials Unit (MRC CTU) at University College London (UCL), analyzed samples from the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) in which over 200,000 women were enrolled, randomized to no screening or annual screening, and followed for up to 20 years. All trial participants donated a blood sample at the time of enrollment. Mercy analyzed blood samples from trial participants to assess the sensitivity and specificity of the Mercy Halo test for detecting ovarian cancer up to three years prior to clinical diagnosis.

Making a Breakthrough

Despite decades of effort, no test method has demonstrated the sensitivity and specificity to merit broad use in screening. CA125 serum biomarker testing and transvaginal ultrasound imaging fail to detect many early-stage ovarian cancers and too often incorrectly classify healthy women as potentially having cancer, resulting in unnecessary diagnostic workup. In this study, Mercy Halo outperformed CA125 in both the ability to detect HGSC (82% vs 63%) and specificity (98% vs 96%), significantly increasing the number of cancers identified, and reducing the number of false positives by almost half.

“This breakthrough is a testament to Mercy’s dedication to the development of innovative approaches to early cancer detection,” said Mercy BioAnalytics Board Chair Stanley Lapidus, a longtime life sciences executive whose innovations helped revolutionize colorectal and cervical cancer screening in the U.S. through founded companies including Exact Sciences and Cytyc. “These highly encouraging results suggest the Mercy Halo test may finally address this major unmet need and potentially save many lives.”

Further Reading: New Test Could Identify Aggressive Ovarian Cancers Early

Ovarian cancer is one of the leading causes of cancer death among women and will kill nearly 13,000 women in the U.S. this year. More than 70% of ovarian cancer is diagnosed in women over 50 years of age, and nearly 80% of ovarian cancer is diagnosed at an advanced stage of disease, when survival is poor. Unfortunately, legacy diagnostic test methods have not shown adequate clinical performance to enable broad adoption for ovarian cancer screening.

“One in 78 women will develop ovarian cancer in her lifetime, and today most of these women will die from their disease. Early detection creates an opportunity to change this paradigm.” says Dawn Mattoon, PhD, Mercy’s chief executive officer. “Mercy has made rapid progress developing high quality, low-cost tests for cancer screening, and this study brings us closer to the day when we can provide women with another effective tool to help proactively manage their health.”

The Mercy Halo Test: An Overview

The Mercy Halo test achieves high performance through the simultaneous detection of multiple cancer-related biomarkers co-localized on the surface of individual tumor-associated extracellular vesicles. The high abundance of extracellular vesicles in circulation enables the Mercy Halo test to be run on a very small volume of serum or plasma with a simple qPCR-based read-out, unlike cell-free DNA-based tests which typically require a larger volume of blood and next-generation sequencing to generate results.

“The superior performance of the Mercy Halo test in comparison to serum CA125 in this initial study is promising, given the rigor of evaluation and the use of the best possible CA125 cut-off for this population, unlike previous studies. We look forward to working with Mercy to further evaluate the test using samples from the multimodal screening arm of UKCTOCS,” said Professor Usha Menon at MRC CTU at UCL, Chief Investigator of UKCTOCS.

The Mercy ovarian cancer data will be shared on June 3rd in a poster titled “Evaluation of a novel extracellular vesicle (EV) based ovarian cancer (OC) screening test in asymptomatic postmenopausal women.” The abstract is available on ASCO’s website.