Biomarker for aggressive fibrotic tumours gets FDA backing

A blood test in development that may be able to predict whether a solid tumour will be particularly aggressive has been given the support of the FDA.

The experimental assay from Danish biotech Nordic Bioscience detects PRO-C3, a peptide released from type III collagen when it is being formed, which is also being investigated as a biomarker for other diseases, including non-alcoholic fatty liver disease (NAFLD).

The FDA has given Nordic Bio a ‘letter of support’, which recognises that a biomarker has potential and encourages further development. It’s not an endorsement or a validation as such, but rather a way to “enhance the visibility of the biomarker, encourage data sharing, and stimulate additional studies,” according to the regulator.

So far, a couple of dozen letters of support have been sent by the FDA, part of a programme to stimulate the identification of new biomarkers that may be used to aid drug development and enable more targeted therapy.

In the case of PRO-C3, the letter states that the FDA would like to see further study of its potential as a prognostic biomarker for survival outcomes in clinical trials of patients with solid tumours; for example, to stratify patients into studies according to their likelihood of survival.

At the moment, the only way to determine fibrosis in tumours is to take a tissue biopsy, stain it to reveal collagen, and examine it under a microscope. A blood test would be easier to apply in a clinical context, and the ability to identify patients at greater risk of events could reduce the sample sizes needed to show an effect in studies.

According to Nordic Bio’s chief executive, Morten Karsdal, PRO-C3 could become the world’s first blood-based fibrosis biomarker for patients with aggressive solid tumours and the FDA’s support will pave the way for further testing of its assay.

“This recognition aligns with our belief in the biomarker’s potential,” he said. “Ultimately, this is all about helping patients fight cancer by supporting drug developers in bringing treatments to market faster and at a lower cost.”

Nordic Bio already has an agreement with diagnostics giant Roche to make the PRO-C3 assay available on its widely-used cobas blood testing platform.

PRO-C3, meanwhile, isn’t the first biomarker for which Nordic Bio has been given the form of FDA support.

In 2021, the biotech and partners Bristol-Myers Squibb and the University of Pennsylvania received a letter from the FDA for PRO-C6, a peptide release in the formation of type V collagen, which may be able to predict outcomes in clinical trials of patients with heart failure with preserved ejection fraction (HFpEF).