Justin Drake, PhD, explains the Certitude Breast blood test for early breast cancer detection

A blood-based proteomic classifier developed by Astrin Biosciences demonstrated 92.3% sensitivity and 92.6% specificity for early-stage breast cancer detection in a retrospective validation study of 1,259 women, according to data presented at the 2026 American College of Obstetricians & Gynecologists (ACOG) Annual Clinical & Scientific Meeting in Washington, D.C.

The findings, drawn from the poster "Deep Plasma Proteomics for Early-Stage Breast Cancer Detection," highlight the potential that Certitude Breast may offer a clinically meaningful option for women with dense breast tissue, a population for whom standard mammography has limitations.

Justin Drake, PhD, Chief Science Officer, Astrin Biosciences, and Associate Professor at the University of Minnesota, framed the unmet need directly:

"About 60% of those cancers are actually missed with traditional mammograms" in women classified as BI-RADS C or D. While supplemental imaging, such as MRI, can improve detection in this population, Drake noted it introduces its own trade-offs.

"For MRI, we're on par with sensitivity, but MRI comes with a much reduced specificity. So that can lead to a lot of false positives. We're similar to ultrasound on specificity, but we are far above the sensitivity of an ultrasound, so we can find more cancers."

Proteomics over nucleotide-based approaches

A key distinction of Certitude Breast is its reliance on plasma proteomics rather than circulating tumor DNA, the basis of most multicancer early detection tests currently on the market, Drake noted.

"Breast and prostate cancer in particular, they don't shed DNA into the bloodstream in any high, sufficient quantities to be detectable at early-stage disease."

"Cancer doesn't form in a vacuum," Drake said. "Cancer cells signal to other cells in the body; they signal to immune cells, they signal to stromal cells. That crosstalk and that signaling between those cells is typically done at the protein level, so we can pick those proteins up."

Per the poster data, the retrospective study included a training cohort of 845 women (466 healthy, 379 cancer) and a blinded validation cohort of 397 women (195 healthy, 202 cancer), using a 70:30 split. All cancer samples were from newly diagnosed, treatment-naïve patients. The classifier achieved greater than 84% sensitivity in Stage 0 disease and consistent performance across demographic and tumor subgroups, including triple-negative breast cancer.

Additionally, sensitivity across subtypes, including triple-negative breast cancer, had 93.8% sensitivity.

Intended use and prospective validation

“As we roll out our test as an LDT, it's intended for women following a screening mammography who require additional risk stratification before further imaging,” he said. “It's most appropriate for women over age 40 with dense breast tissue, so again, BI-RADS C or D, who have had a negative screening mammogram, and then patients with inconclusive or indeterminate mammograms, so this would be BI-RADS 0 or 3, or high-risk patients with negative or equivocal mammograms. This would be used as part of a high-risk screening rotation, or for women with suspicious or positive findings from a mammogram, this would be BI-RADS 3 or 4.”

Prospective validation is ongoing. According to the poster, a 4,500-patient screening study with Mayo Clinic is underway, with additional focus on dense breast populations. Drake indicated that full results from an interim prospective analysis in women undergoing biopsy are expected in Q3 or Q4 of 2025.

Related to the regulatory process, Drake told Contemporary OB/GYN:

“Certitude was developed and validated by Astrin Biosciences Laboratories, which is accredited by CAP, certified under CLIA regulations, and qualified to perform high-complexity clinical laboratory testing. Most blood tests are not individually approved by the FDA. Instead, they are performed in CLIA-certified and CAP-accredited laboratories, which are regulated to ensure tests are accurate, reliable, and safe for patient care. Certitude falls into this category, meaning the test is validated and performed in a highly regulated laboratory environment that meets strict quality standards. At this stage, Certitude has completed analytical validation, and these findings help further demonstrate the test’s consistency and clinical potential in a real-world laboratory setting.”

Reference:

Horrmann A, Travadi Y, Mallery K, et al. Deep Plasma Proteomics for Early-Stage Breast Cancer Detection. Poster. American College of Obstetricians & Gynecologists Annual Clinical & Scientific Meeting. May 1-3, 2026. Washington, D.C.