Renalytix has achieved a significant milestone after a challenging three-year journey by obtaining FDA authorization for its revolutionary prognostic test, designed to anticipate the onset of kidney function decline. The United Kingdom-based company initially submitted its advanced KidneyIntelX test platform to the FDA for review in August 2020, following the agency’s recognition of the technology as a breakthrough device.
During the annual J.P. Morgan Healthcare Conference in January of the following year, Renalytix CEO James McCullough addressed the prolonged review process and empathized with the FDA’s workload. McCullough acknowledged the progress being made and anticipated obtaining FDA clearance in 2022. However, the timeline was later revised to the first quarter of the current year and further extended to the second quarter. Remarkably, Renalytix managed to meet this target and recently announced the receipt of de novo clearance.
Approximately one month after the initial submission, Renalytix launched the KidneyIntelX test as a laboratory-developed test (LDT), which allowed the company to bypass FDA clearance on the condition that the test was produced and used within a single laboratory. The LDT version was initially introduced at New York City’s Mount Sinai Health System, the institution where the technology underlying the KidneyIntelX test was developed before being licensed to Renalytix. The company reported that the LDT test has been administered to around 10,000 patients across the United States.
While the test will continue to be available as an LDT under the name KidneyIntelX, it will now be commercially accessible on a wider scale as the FDA-cleared KidneyIntelX.dkd. The additional “dkd” refers to diabetic kidney disease, a specific form of chronic kidney disease caused by diabetes mellitus, which is the leading underlying cause of kidney disease according to the National Institutes of Health.
The KidneyIntelX.dkd test utilizes an artificial intelligence algorithm to analyze specific biomarkers in a patient’s blood sample, along with additional data points from the individual’s electronic health record. The AI algorithm generates a risk score indicating whether the patient is at low, moderate, or high risk of experiencing a progressive decline in kidney function within the next five years. A study published in early 2021 demonstrated the test’s effectiveness, with KidneyIntelX achieving an area under the curve (AUC) of 0.77 in predicting declining kidney function, compared to an AUC of 0.61 for a conventionally used clinical model.
Currently, the test primarily focuses on predicting declining kidney function in individuals with Type 2 diabetes and early-stage chronic kidney disease. However, McCullough hinted at the potential for Renalytix’s technology to explore additional applications following the FDA clearance. The CEO expressed that the FDA’s clearance establishes a new category known as the “Prognostic Test for Assessment of Chronic Kidney Disease Progression,” paving the way for future expansion of KidneyIntelX into new indications and product offerings.
