Published research reports lung cancer CTC enrichment using Parsortix

ANGLE plc, the specialist medtech company, is delighted to announce that Cancer Research UK Manchester Institute has published highly encouraging results from its work in lung cancer patients using ANGLE's Parsortix system in the Royal Society of Chemistry's publication, Analyst.

Lung cancer is the most common cancer in the world. More than 1.8 million cases of lung cancer were recorded in 2012, accounting for around 13 per cent of all new cancer cases (Source: World Cancer Research Fund International). Effective treatment for lung cancer is dependent on the cancer status which is determined through biopsy. However, where traditional solid biopsies are invasive and can harm the patient, liquid biopsies offer a non-surgical, patient-friendly alternative.

Ged Brady, Deputy and Genomics Leader within the Clinical & Experimental Pharmacology group at Cancer Research UK Manchester Institute, commented:

"The Parsortix system has a unique combination of features making it suitable for routine clinical analysis of patient blood samples. We have now incorporated the Parsortix workflow into multiple clinical trials and have been accumulating many hundreds of stored enriched samples that will be of immense value in our future CTC studies."

ANGLE's Founder and Chief Executive, Andrew Newland, added:

"This is our second peer-reviewed publication in a scientific journal and adds to the growing body of published evidence of Parsortix's performance as a liquid biopsy. The success in pilot studies in harvesting CTCs from 100% of small-cell lung cancer patients comes after similar performance with 100% of prostate, breast and ovarian cancer types. We believe Parsortix is changing the paradigm for CTC capture and harvest for liquid biopsy and will change CTC molecular analysis from being a theoretical but impractical goal to being simple and effective in hospital laboratories all over the world. The prospect of deployment of our repeatable, non-invasive liquid biopsy in the treatment of lung cancer patients is exciting and has the potential to make a major impact in improving future cancer care."

CRUK MI undertook a clinical head-to-head comparison of Parsortix with CellSearch, the only CTC (circulating tumour cell) technology currently approved by the FDA¹ and thus the current "gold standard" in CTC detection. The comparison was undertaken with small cell lung cancer (SCLC), a particularly aggressive form of lung cancer, as it is known to be a cancer where CellSearch is considered to perform well as a result of large numbers of EpCAM +ve CTCs. In this pilot study:

• Paired blood samples were taken from 12 patients with SCLC for enrichment and enumerated by both CellSearch and Parsortix
• Parsortix captured and harvested for analysis 20 or more CTCs in all 12 samples (100%)
• CellSearch identified CTCs in 10 out of 12 samples but, of these, three samples contained fewer than five CTCs
• At the five cell cut-off, CellSearch only managed to isolate CTCs for 7/12 patients (58%) compared to Parsortix's 12/12 patients (100%)

A further important differentiation of the Parsortix system is that CRUK MI adopted a workflow that first removed plasma from the blood sample, before running the cell component of the sample on Parsortix. In all 11 samples where it was undertaken, significant levels of cell-free DNA (cfDNA) could be purified. CRUK MI thus demonstrated that using Parsortix a single blood sample can be used for both cfDNA and CTC analysis. There are many research groups focused on cfDNA analysis. CRUK MI's work in this area clearly demonstrates Parsortix's capability to work in tandem with these approaches to provide additional clinical information, for example RNA and protein expression.

ANGLE considers the findings reported in the Analyst publication, which, in addition to the clinical work on lung cancer, reports on extensive work that CRUK MI have undertaken on the system since 2012, to be of great importance in demonstrating the potential value of the Parsortix in future cancer care. Key points extracted from the publication's conclusion section include:

"In summary, the approach we have described offers a unique combination of features making it suitable for routine clinical analysis of patient blood samples.

Firstly, the epitope independent CTC enrichment approach we have devised is compatible with whole blood stabilisation reagents suitable for at least four days at room temperature.

Secondly, CTC enrichment takes place in a simple plug and play device that remains sealed throughout the enrichment step and the enriched cells are eluted directly into a collection tube for further analysis.

Thirdly, the approach delivers both plasma for cfDNA analysis and cells for CTC enrichment, enabling direct comparisons of molecular readouts from both cfDNA and CTC.

Fourthly, enriched CTC samples can be banked for later analysis providing the much needed flexibility often required to select relevant subsets of samples as well as analytical approaches appropriate to specific clinical trials and biological questions.

Finally, our initial clinical results with SCLC patient blood samples clearly demonstrate that the CTC enrichment process we have developed identifies subsets of CTCs not readily detected by epitope dependent technologies thereby facilitating more extensive CTC analysis which may help determine the underlying patient cancer status providing the potential for improving patient outcomes."