Launch of PD-L1 test to support cancer studies

ANGLE's Portrait PD-L1 test uses CTCs harvested from the Parsortix system to investigate real-time patient PD-L1 status for clinical studies

The test is designed for highly accurate, repeatable, and precise results for CTC PD-L1 biomarker expression

ANGLE plc (AIM:AGL OTCQX:ANPCY), a world-leading liquid biopsy company with innovative circulating tumour cell (CTC) diagnostic solutions for use in research, drug development and clinical oncology, is delighted to announce the launch of its Portrait® PD-L1 test for the evaluation of PD-L1 protein expression on CTCs following extensive development and optimisation. The test is provided as a service from ANGLE's Onc-ADaPT® GCP-compliant laboratories and is conducted by an expert team with over 10 years' experience in CTC analysis.

PD-L1 is an immune-related biomarker that can be expressed on the surface of tumour cells across a range of cancer types, and expression of this biomarker enables cancer cells to evade immune response mechanisms that would typically keep abnormal cell growth in check. Consequently, PD-1/PD-L1 inhibitors have emerged as the leading immunotherapy treatment option with over 2,800 active interventional studies in progress involving 430,000 patients.

The output of current tumour tissue-based PD-L1 tests varies considerably, with poor performance often unavoidable due to the elapsed time between tissue biopsy (generally taken at diagnosis and difficult or impossible to repeat) and disease progression (which may be months or years later) when immunotherapies are considered, during which time PD-L1 status can change. ANGLE has developed its immunofluorescence (IF) based test for the determination of PD-L1 status on CTCs to allow real-time assessment of biomarker status, which may address this fundamental flaw in current PD-L1 tests via a simple blood test.

ANGLE's Portrait PD-L1 service is an end-to-end solution using ANGLE's world leading Parsortix CTC technology to deliver:

• minimally invasive liquid biopsy with sample stability up to five days post-blood collection
• biomarker independent harvest of phenotypically diverse CTCs from a simple blood test
• identification and enumeration of CTCs with accurate, precise assessment of PD-L1 status (see https://angleplc.com/onc-adapt-laboratories/portrait-pd-l1/)
• longitudinal monitoring of PD-L1 status over multiple time points including before, during and after the patient receives the treatment.

It is well established that the number of CTCs is prognostic of cancer treatment response, recurrence, and relapse and this has been documented in numerous peer-reviewed publications. It is now evident that changes in CTC numbers and their PD-L1 status can provide an early indication of immunotherapy treatment resistance and progressive disease. Studies have also shown that CTCs isolated from patients with solid cancers and expressing PD-L1 may serve as a clinically actionable biomarker for immunotherapy.

The global PD-1 and PD-L1 immunotherapy market is currently valued at US $36.9 billion per annum, and analysts predict the market to reach US $109.1 billion by 2032. Despite the rapid expansion of the immunotherapy market, with many indications approved under accelerated approval, this class of drug has been challenged by the withdrawal of a range of indications due to the failure to subsequently confirm the clinical benefit in such indications in larger trials. As such, a test that can help with patient stratification in biopharmaceutical drug trials, and act as an early predictor of treatment response and disease recurrence could provide earlier insight into critical efficacy endpoints.

ANGLE Founder and Chief Executive, Andrew Newland, commented:

"Whilst immune checkpoint inhibitors have achieved remarkable progress in tumour treatment, the cost of treatment is high and currently the majority of patients fail to respond.

ANGLE's Portrait PD-L1 test provides accurate, repeatable, and precise PD-L1 identification on CTCs and hence has the potential to streamline patient selection and optimise PD-L1 monitoring for treatment response and disease progression throughout clinical studies.

We are now beginning an active promotion of this test to biopharma customers."

For Research Use Only. Not for use in diagnostic procedures.