Abstract: FR-OR026
Clinical Study Evaluating Accuracy of the Transdermal (GFR) Methodology in Patients with CKD
Session Information
- CKD: Identifying Risks and Optimizing Outcomes
November 07, 2025 | Location: Room 362A, Convention Center
Abstract Time: 05:40 PM - 05:50 PM
Category: CKD (Non-Dialysis)
- 2302 CKD (Non-Dialysis): Clinical, Outcomes, and Trials
Authors
- Goldstein, Stuart, MediBeacon Inc, St. Louis, Missouri, United States
- Dorshow, Richard B., MediBeacon Inc, St. Louis, Missouri, United States
- Johnson, James R., MediBeacon Inc, St. Louis, Missouri, United States
- Riley, I. Rochelle, MediBeacon Inc, St. Louis, Missouri, United States
- Vitale, Laura, MediBeacon Inc, St. Louis, Missouri, United States
- Friedemann, Jochen, MediBeacon Inc, St. Louis, Missouri, United States
- Ross-Jones, Jesse, MediBeacon Inc, St. Louis, Missouri, United States
Background
Chronic kidney disease is most often staged using endogenous marker based empirical equations to estimate GFR (eGFR). However, eGFR is known to be inaccurate for individual patients. Plasma-derived GFR using exogenous agents is the preferred methodology for GFR determination, as noted by FDA guidelines. The necessity of multiple blood draws and laboratory analysis limit use in standard clinical practice and is thus mainly relegated to the research arena.
We have shown the fluorescent tracer agent relmapirazin is an exogenous GFR tracer agent. Using transdermal fluorescence detection of relmapirazin, we have shown that a clinically relevant range of GFR can be assessed across all human skin colors. Thus this method melds the use of an exogenous GFR tracer agent with clinical GFR determination performed at the point-of-care.
In the current study, we evaluated the accuracy of this transdermal methodology. Transdermal GFR (tGFR) as determined by the transdermal detection system is compared to the plasma-derived indexed GFR (nGFR) in a multi-center pivotal clinical study.
Methods
This prospective study evaluated 182 participants with normal and CKD stage 1-4 kidney function. This population included participants in each of the six Fitzpatrick Skin Scale (FSS) types. A sensor attached on the upper chest of each participant contained an LED and photodetector for transdermal fluorescence detection following IV-administration of relmapirazin. Statistical comparison was made using the P30 statistic for tGFR with respect to nGFR as an ensemble, and for subgroups stratified by CKD stage and FSS.
Results
P30 of 94% (95% CI 89-97%) was obtained for the entire ensemble of participants. P30 was 96% and 92% for participants with GFR greater than and less than 60 mL/min/1.73m2 respectively. P30 of 96% for participants with FSS I-III and 90% with IV-VI was observed. Comparison was made to P30 of the standard creatinine-based eGFR equations in use today (Table 1).
Conclusion
The tGFR P30 is superior to the P30 of the eGFR equations employed in standard clinical practice today.
Table 1. P30 Comparison
| GFR Method | P30 (%) | 95% Confidence Interval |
| tGFR | 94.0 | 89.4 - 96.9 |
| CKD-EPI 2009 eGFR | 84.1 | 83.0 - 85.3 |
| CKD-EPI 2021 eGFR | 79.2 | 78.5 - 79.9 |
Funding
- Commercial Support – MediBeacon Inc.