Landmark Study from Mercy BioAnalytics and University College London Demonstrates Significant Improvement Over CA125 and Ultrasound for Ovarian Cancer Screening

May 23, 2024

Mercy Halo™ Test demonstrates 82% sensitivity and 98% specificity in a retrospective blinded analysis of prospectively collected samples from 1300 asymptomatic women


WALTHAM, Mass., May 23, 2024 /PRNewswire/ — Mercy BioAnalytics, Inc., a pioneer in extracellular vesicle-based liquid biopsy for the early detection of cancer, will present data at the American Society of Clinical Oncology Annual Meeting next month 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.

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.

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.”

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.

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.

“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.” said Dawn Mattoon, Ph.D., 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 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 today on ASCO’s website.

About Mercy BioAnalytics
Mercy BioAnalytics, Inc. is on a mission to relieve suffering and save lives through the early detection of cancer. Early-stage cancer is difficult to detect, but when found, is more often amenable to curative therapy. The patented Mercy Halo™ liquid biopsy platform utilizes biomarker co-localization to interrogate highly abundant, blood-based extracellular vesicles that carry unique cancer signatures from their parent cells. The Mercy Halo platform is designed to detect Stage I cancer, when it is most treatable, and enhance the quality of life for cancer patients and their families. Mercy’s initial focus is the early detection of ovarian and lung cancers. Ovarian cancer, the most lethal gynecological cancer, typically goes undetected until it is too late to cure. Lung cancer, the number-one cancer killer, takes more lives than breast and prostate cancers combined.

About Medical Research Council Clinical Trials Unit at University College London
The MRC CTU at UCL is at the forefront of resolving internationally important questions in infectious diseases and cancer and delivering swifter and more effective translation of scientific research into patient benefits. It does this by carrying out challenging and innovative studies, and developing and implementing methodological advances in study design, conduct and analysis.

UKCTOCS is the largest ovarian cancer screening trial to date. Over 200,000 eligible postmenopausal women from the general population, aged 50–74 years, with intact ovaries were recruited between 2001 and 2005 and randomly allocated (2:1:1) to no screening or annual screening (multimodal screening or ultrasound screening) until Dec 31, 2011. Follow-up was through national registries until 2020. There was no reduction in deaths due to ovarian cancer in either screening arms compared to no screening. However, in the multimodal screening arm, fewer women with high grade serous ovarian cancer were diagnosed with advanced stage disease and had improved short-term outcomes. While the trial findings do not support ovarian cancer screening using CA125 and ultrasound, they suggest that novel approaches that can detect more women earlier in the course of the disease are likely to positively impact mortality.