Test X is an in vitro quantitative blood test designed to predict incident diabetic kidney disease (DKD) or progression of DKD in patients with type 2 diabetes mellitus (T2DM) before kidney damage occurs. Test X will be submitted to the Medical Services Advisory committee (MSAC) for listing consideration on the Medicare Benefits Schedule (MBS).
Test X detects three protein biomarkers (analytes) in human plasma:
- Biomarker-1 Apolipoprotein A4 (ApoA4);
- Biomarker-2 CD5 antigen-like (CD5L); and
- Biomarker-3 Insulin growth factor binding protein 3 (IBP3).
The concentration of the biomarkers, along with clinical factors (age, HDL-cholesterol, eGFR), are entered into the Test X Hub, a proprietary software algorithm which characterises each patient as having low-risk, moderate-risk or high-risk of developing DKD (defined as eGFR below 60 mL/min/1.73m2) within the next four years or a decline in eGFR of ≥30% over four years.
Test X results are presented as a percentage risk score. The cut-offs that are used to determine the 4-year risk of developing DKD are: Test X score of <10% for low-risk, 10% to <20% as moderate-risk and ≥20% as high-risk (see Figure 1).
Figure 1. Test X risk categories for incident DKD risk within the next four yearsThe turnaround time for Test X may be up to 7 days.
Test Accuracy:In validated clinical studies, Test X predicted 86% of otherwise healthy diabetics who went on to develop DKD within four years.
| Test X Sensitivity: ability of the test to correctly identify those at high risk of DKD (true positive)
| 86% |
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| 1 | Test X Specificity: ability of the test to correctly identify those at low risk of DKD (true negative) | 78% |
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| 2 | Negative Predicative Value (NPV): probability that a patient with a low-risk test result will not develop DKD | 98% |
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(20min delay)