Proteomics International Laboratories Ltd’s (ASX: PIQ) prototype diagnostic test for oesophageal adenocarcinoma has shown strong diagnostic performance detecting up to 90% of people with the frequently fatal condition.
The results have been presented at the 18th World Congress for Esophageal Diseases being held virtually, and in Tokyo, Japan 26-28 September 2022.
Oesophageal adenocarcinoma is the most common form of oesophageal cancer and is an area of significant unmet medical need, with current screening requiring a specialist endoscopy procedure that costs US$2,750 per patient in the United States, where the total expenditure on treating oesophageal cancer was $2.9 billion in 2018. The overall five-year survival rate for this cancer is less than 20%, and one in 20 cancer deaths worldwide in 2018 were attributed to oesophageal cancer.
Proteomics International Managing Director Dr Richard Lipscombe said the results were an exciting milestone in the development of a new accurate, easy to use test for oesophageal adenocarcinoma using biomarkers—protein ‘fingerprints’ in the blood—to diagnose the disease.
The test is targeted at both oesophageal adenocarcinoma and patients with Barrett’s oesophagus, a pre-malignant condition associated with an increased risk of oesophageal adenocarcinoma. An estimated 10-15% of patients with chronic acid reflux develop Barrett’s oesophagus, a condition which is asymptomatic and affects one to two per cent of Western populations. People with Barrett’s oesophagus are much more likely to get oesophageal adenocarcinoma, and are advised to get regular endoscopies to screen for oesophageal cancer.
These results form the basis for a simple blood test for the disease. It’s a significant step towards diagnosing this cancer earlier without the need for an endoscopy,” Dr Lipscombe said.
The Oesophageal Cancer Diagnostic is Proteomics International’s latest test from the Company’s Promarker pipeline. The results build on a successful collaboration with the QIMR Berghofer Medical Research Institute which validated a select panel of biomarkers in a study of more than 300 patients across two independent clinical cohorts. Proteomics International owns the exclusive worldwide rights to commercialise the biomarkers, which are patented in multiple jurisdictions.
In the current study a series of statistical models were developed to assess the accuracy of the biomarker panel in diagnosing different levels of disease severity, from oesophageal adenocarcinoma to a comparison with the pre-malignant condition of Barrett’s oesophagus as well as a comparison to healthy controls.
These novel diagnostic tools demonstrated that the biomarkers added statistically significant (P<0.05) performance to the clinical models, with the validated performance for sensitivity (Sn) of 76-90% across the key categories, with specificity (Sp) of 64-89%, and Area Under the Curve (AUC) scores of 0.71-0.87.
For comparison, the statistical performance of the Prostate-Specific Antigen (PSA) diagnostic test (blood test measuring the concentration of the PSA protein) for the diagnosis of prostate cancer is:
- Prostate cancer versus no cancer: AUC 0.68, P = <0.001
- PSA cut-off threshold 3ng/ml: Sensitivity 32%, Specificity 87%
Dr Lipscombe said the next steps in commercialising the prototype test are to:
- further develop the statistical modelling to improve the test’s sensitivity and specificity. This will use the ‘traffic light’ system developed for the Company’s PromarkerD predictive test for diabetic kidney disease;
- refine the reproducibility of the biomarker measurements to produce a test suitable for the US Laboratory Developed Test (LDT) pathway via CLIA certified clinical laboratories;
- confirm the clinical performance of the test in an additional independent patient cohort;
- conduct formal Economic Health Benefit Modelling and Clinical Utility Studies to demonstrate how the new test could significantly change doctors’ treatment decisions and improve outcomes for patients and healthcare systems.
