NASHVILLE, Tenn. — March 13, 2026 — Leads & Copy — Insight Molecular Diagnostics Inc. (Nasdaq: IMDX) highlighted a new peer-reviewed study demonstrating the potential superiority of its GraftAssureTM assay technology.
The study, featured in Transplant International and titled “Donor-Derived Cell-Free DNA as a Non-Invasive Readout of Activity Across the Rejection Continuum,” involved investigators from Heidelberg University Hospital and Charité – Universitätsmedizin Berlin, along with iMDx scientist authors. The study included 249 biopsy-matched patients.
The company believes the new study, combined with data presented at the World Transplant Congress in 2025, supports the growing clinical differentiation and marketability of the GraftAssure technology and reinforces iMDx’s strategic vision. iMDx seeks to deliver an industry-leading molecular diagnostic test kit for clinical use that expands and improves access to organ health testing for kidney transplant patients.
iMDx anticipates that enabling localized testing will deliver new value in the roughly $2 billion-plus addressable market for regulated transplant rejection testing.
The peer-reviewed publication reports on 249 patients who underwent clinically indicated kidney transplant biopsies from two independent cohorts. The study compared dd-cfDNA measurements in blood plasma with newly developed histopathology-derived rejection indices that quantify transplant rejection activity across a continuous biological spectrum.
The study found that dd-cfDNA levels increased with histological evidence of graft inflammation, with the strongest associations observed in microvascular inflammation (MVI) and antibody-mediated rejection (AMR), which are the most clinically significant forms of transplant rejection.
IMDx’s GraftAssure Combination Model (CM)-score combines the relative (percentage) and absolute (copies per milliliter) measurements of DNA fragments from the transplanted organ. According to the study, the correlation between the GraftAssure CM-score and rejection indices suggests that the assay measures complex biological signals in kidney transplantation.
GraftAssure’s CM-score outperformed both fractional and absolute measures on their own in correlation analyses with the four indices of transplanted organ health: Antibody-mediated Rejection / Microvascular Inflammation (AMR/MVI index), T-Cell Mediated Rejection / Tubulointerstitial Inflammation (TCMR/TI index), Activity index, and Chronicity index. The rejection (AMR/MVI and TCMR/TI) indices were of particular interest to investigators because they are known to have a strong association with graft survival.
Study authors also presented data at the World Transplant Congress in 2025 that showed an improvement in positive predictive value from around 50% seen in the literature to an unprecedented value of above 80% using the GraftAssure CM-score (at 25% prevalence, which is often seen in for-cause settings) enabling the rule-in option for transplanted organ rejection for the first time. That study is currently under review for publication.
iMDx Chief Science Officer Prof. Dr. Ekkehard Schuetz, a co-author of the study, said kidney transplant rejection is understood as a biological continuum rather than a simple yes-or-no diagnosis. He added that the results show that dd-cfDNA measured in the blood mirrors the inflammatory activity observed in transplant biopsies.
Schuetz also noted that one unexpected finding was that in TCMR, the total cell-free DNA increases with severity, which resulted in a loss of correlation for dd-cfDNA when reported as percentage. However, the Combination Model score showed the strongest correlation with TCMR, supporting the concept that integrated blood-based monitoring can provide clinicians with a real-time view of graft immune activity and help guide earlier intervention as rejection begins to develop.
The study was investigator-initiated and investigator-led. Insight Molecular Diagnostics provided dd-cfDNA measurements used in the analysis.
iMDx is commercializing its transplant testing technology, which quantifies donor-derived cell-free DNA (dd-cfDNA), using a market-disruptive business strategy under the GraftAssureTM brand. The company’s transplant diagnostics include GraftAssureCore, a laboratory-developed test (LDT) currently reimbursed by CMS and performed at iMDx’s CLIA-certified laboratory in Nashville; GraftAssureIQ, a research-use-only (RUO) kit; and GraftAssureDx, the in vitro diagnostic (IVD) kit currently in development for use in clinical decision-making.
Insight Molecular Diagnostics is a diagnostics technology company whose mission is to democratize access to novel molecular diagnostic testing to improve patient outcomes.
Source: Insight Molecular Diagnostics Inc.
