CelLBxHealth presents proof-of-concept study using Roche Tissue Diagnostics’ workflow at world-leading drug development conference

• Parsortix platform shown to be compatible with the Roche BenchMark ULTRA automated staining system, with initial study of three key drug targets: HER2 (breast), TROP2 (lung) and PSMA (prostate)

Guildford, UK and Plymouth Meeting PA, USA, – 5 November 2025 – CELLBXHEALTH plc (AIM:CLBX OTCQX:ANPCY), a global leader in circulating tumour cell (CTC) intelligence, announces the presentation of a proof-of-concept study using a Roche Tissue Diagnostics workflow at the 16^th World ADC conference, San Diego, USA (Nov 3-6). The World ADC Conference is the largest global event dedicated to antibody–drug conjugates (ADCs), attracting over 1,400 attendees focused on advancing targeted cancer therapies.

Roche is a major diagnostics player, holding a significant share of the overall tissue testing market. The Roche BenchMark ULTRA system is considered a world leading clinical automated staining platform, with 95 patient samples processed every minute, equating to more than 50 million samples a year¹.

The study showcases a novel workflow combining CelLBxHealth’s Parsortix® platform and proprietary CellKeep slide with Roche’s BenchMark ULTRA automated immunohistochemistry (IHC) staining platform for cell visualisation and biomarker analysis across key ADC targets: HER2, TROP2, and PSMA.

Key findings from the collaboration include:

• Blood samples were successfully processed and cancer cell lines fixed and shipped to Roche Tissue Diagnostics’ site for automated IHC analysis using Roche Tissue Diagnostics’ HER2, TROP2 and PSMA assays

• For all biomarkers the BenchMark ULTRA automated IHC staining was compatible with CelLBxHealth’s manual immunofluorescent staining workflow

Characterisation of CTCs can overcome the limitations of tissue biopsies in cancer care. A simple blood test offers a safer, faster, and less costly alternative, enabling repeated testing when tissue isn’t available. Since cancer changes over time and with treatment, real-time monitoring is critical. As living cells shed from the tumour into the blood, CTCs provide a dynamic and up-to-date view of the patient’s disease status.

The ADC market continues to grow rapidly, driven by the need for targeted, effective treatments with fewer side effects. Integrating CTC-based biomarker assessment into ADC development and clinical use could help optimise patient selection and improve outcomes. CTCs are considered better biomarkers than circulating tumour DNA (ctDNA) for selecting patients for ADC treatment primarily because CTCs allow for the direct analysis of the target protein expression on the cell surface, a critical requirement for ADC efficacy.

Peter Collins, Chief Executive Officer of CelLBxHealth, said: “We are pleased to present initial results on our proof-of-concept study undertaken using Roche Tissue Diagnostics’ workflow. It is well known that targeted treatments that utilise biomarkers improve patient outcomes. As such, this study highlights the importance of targeted antigen expression on CTCs and their relevance for potentially guiding ADC therapy selection in real-time.

CelLBxHealth believes these results highlight CTCs as accessible, dynamic biomarkers in oncology. Leading experts believe that CTCs are poised to add clinical utility to the metastatic landscape².”

For more information, visit www.cellbxhealth.com.

References:

1. www.diagnostics.roche.com/us/en/products/instruments/discovery-ultra-ins-2210.html

2. Nicolò, E., et al. (2025). International expert consensus on the clinical integration of circulating tumor cells in solid tumors. European Journal of Cancer, 231, 116050. https://doi.org/10.1016/j.ejca.2025.116050