PreludeDx Presents New Data at AACR Confirming No Significant Radiation Benefit in DCISionRT Low-risk Patients

DCISionRT Demonstrated to Be Superior Predictor of Risk Recurrence
and RT Benefit over Traditional Clinpath

LAGUNA HILLS, Calif., Sept. 9, 2022 /PRNewswire/-- Prelude Corporation (PreludeDxä), a leader in molecular diagnostics and precision medicine for early-stage breast cancer, announced compelling results in 926 women diagnosed with ductal carcinoma in situ (DCIS) identifying patients with low risk of recurrence independent of traditional clinicopathologic risk factors. Study results were presented today at the American Association for Cancer Research (AACR) Special Conference: Rethinking DCIS: An Opportunity for Prevention.

The DCISionRT^® test demonstrated that radiation did not significantly reduce the in-breast recurrence (IBR) rate in the low-risk group. However, the elevated/residual-risk group benefited significantly from radiation therapy (RT), with a 17.7% absolute 10-year IBR rate reduction.

"DCISionRT is a major step forward in treatment decision making for DCIS patients," said Rachel Rabinovitch, MD, FASTRO, Professor, Radiation Oncology, University of Colorado. "DCISionRT is the first biosignature specific for radiation therapy efficacy, here in the setting of adjuvant RT for DCIS. This assay can help us confidently identify a true low-risk group after lumpectomy, enabling de-escalation of radiation therapy and a high-risk group, many of whom benefit more than a relative 50% from adjuvant RT. The power of the study demonstrated that you would need to treat 100 patients in the low-risk group to benefit just one patient."

"We are honored to participate in this AACR Special Conference dedicated solely to enhancing the care of DCIS patients and present our latest clinical data demonstrating the applicability of DCISionRT to guide DCIS treatment decisions," said Dan Forche, President and CEO of PreludeDx. "DCISionRT is an important risk assessment tool to determine which patients can safely omit RT, which patients will benefit greatly from RT, and which patients may need more aggressive therapy."

DCISionRT is the only risk assessment test for patients with ductal carcinoma in situ (DCIS) that predicts radiation therapy benefit. Patients with DCIS have cancerous cells lining the milk ducts of the breast, but they have not spread into surrounding breast tissue. In the US, over 60,000 women are newly diagnosed with DCIS each year. DCISionRT, developed by PreludeDx on technology licensed from the University of California San Francisco, and built on research that began with funding from the National Cancer Institute, enables physicians to better understand the biology of DCIS. DCISionRT combines the latest innovations in molecular biology with risk-based assessment scores to assess a woman's individual tumor biology along with other pathologic risk factors and provide a personalized recurrence risk. The test provides a Decision Score^TM that identifies a woman's risk as low or elevated. Unlike other risk assessment tools, the DCISionRT test combines protein expression from seven biomarkers and four clinicopathologic factors, using a non-linear algorithm to account for multiple interactions between individual factors in order to better interpret complex biological information. DCISionRT's intelligent reporting provides a woman's recurrence risk after breast conserving surgery alone and with the addition of radiation therapy. In turn, this new information may help patients and their physicians to make more informed treatment decisions.

PreludeDx is a leading personalized breast cancer diagnostics company dedicated to serving breast cancer patients and physicians worldwide. Founded in 2009 with technology licensed from University of California San Francisco, PreludeDx has focused on developing precision breast cancer tools that will impact a patient's treatment decision. Our mission is to provide patients and physicians with innovative technologies that improve patient outcomes and reduce the overall cost burden to the healthcare system. Before making a treatment decision, Know Your Risk^TM. PreludeDx is a Fjord Ventures portfolio company.

For more information on how PreludeDx is making a difference for patients, please visit the Company's website: https://preludedx.com  and follow us on Twitter @PreludeDx, Facebook, Instagram and LinkedIn.

PreludeDx, the PreludeDx logo, DCISionRT, the DCISionRT logo, Decision Score, The DCIS Test, Know Your Risk and Your Biology, Your Decision are trademarks of Prelude Corporation or its wholly owned subsidiaries in the United States and foreign countries.

SOURCE PreludeDx