Promatix Biosciences Highlights the Power of its Logic-Gated Proteomics-Driven Bispecific Discovery Platform to Expand the Tumour-Selective Target Space for Next-Generation ADCs at AACR 2026

  • Scarcity of truly tumour-selective targets remains a key limitation in ADC development, restricting delivery of safe and effective next-generation therapies
  • Promatix’s integrated TxPro + CipherPro platform combines systematic proteomic profiling with computational modelling to identify complementary antigen pairs, expanding the tumour-selective target landscape from a limited set of monospecific targets to thousands of predicted bispecific combinations
  • Experimental validation of a novel EGFR × EphA2 bispecific candidate, the Company’s lead programme, for development in colorectal cancer demonstrates the predictive power of the Promatix platform to translate logic-gated bispecific modelling into biologically actionable targets

 

London and Cambridge, UK — 21 April 2026 — Promatix Biosciences Ltd (Promatix), an emerging UK-based biotechnology company developing innovative new classes of cancer therapies using cis-bispecific antibodies, today is presenting new data at the American Association for Cancer Research (AACR) Annual Meeting 2026. The data demonstrate how the Company’s proprietary integrated proteomics-driven discovery platform addresses a fundamental limitation in antibody-drug conjugate (ADC) development – the scarcity of truly tumour-selective targets – by systematically identifying complementary antigen pairs and significantly expanding the target landscape for next-generation bispecific ADCs.

The data are being presented in a poster titled, “Overcoming the Limited Monospecific Target Landscape in Cancer via Discovery of Tumor-Selective AND- and OR-Gate Bispecifics”. The poster outlines Promatix’s integrated discovery strategy, combining large-scale proteomic profiling (TxPro) with computational modelling (CipherPro) to identify complementary antigen pairs suitable for tumour-selective bispecific targeting. By exploiting hybrid avidity utilizing an AND-Gate, where both antigens are required for binding, Promatix aims to improve tumour selectivity, enhance efficacy and reduce toxicity.

While advances in payloads, linkers, and conjugation technologies have improved ADC performance, target selection remains a key determinant of therapeutic index and continues to limit innovation in the field. This challenge has driven increasing interest in bispecific ADCs and logic-gated targeting strategies designed to improve selectivity and enable safer, more effective therapies.

“Across the ADC field, target selection is increasingly recognized as the critical bottleneck for achieving meaningful improvements in efficacy and safety,” said Dr. Michael Hunter, CEO and Co-Founder of Promatix. “Our integrated platform is designed to overcome this limitation through a systematic, data-driven approach to identifying complementary antigen pairs. It greatly expands the universe of viable tumour-selective targets beyond what conventional monospecific approaches can achieve and provides a scalable foundation for advancing next-generation ADC performance. In ADC development, we believe success will be determined by better targets, which will ultimately lead to better drugs.”

Limited Availability of Tumour-Selective Monospecific Targets Highlights Need for Next-Generation Strategies

Using Promatix’s oncology-focused proteomics database, TxPro, comprehensive profiling of surface protein expression across tumours and normal tissues revealed that truly tumour-selective monospecific targets are rare across tumour types, highlighting fundamental biological constraints of conventional single-target ADC strategies. Of the 2,768 surface proteins evaluated, only 575 showed high cancer expression (above 10,000 copies per cell), and, ultimately, just a small subset of 24 proteins demonstrated strong differential expression (DE) on tumour versus normal tissue.

Notably, targets currently used in approved ADCs for solid tumours do not display strong DE profiles, underscoring the limited availability of highly tumour-specific antigens and the inherent safety challenges associated with single-target approaches. In contrast, several of the high-selectivity targets identified by TxPro correspond to antigens with emerging clinical relevance, including CLDN6, for which encouraging early clinical activity has been reported in ovarian cancer.

Current Bispecific Landscape Shows Limited Target Novelty

The current bispecific landscape continues to rely on a limited number of established antigens, with EGFR and MET dominating many existing programs. Overall, target novelty remains low, with only 15.3% of constructs including at least one unique target and just 2.5% incorporating two novel targets. Among explored programs, EGFR × MET demonstrated the most robust complementary expression, reinforcing its role as a reference benchmark.

Promatix Logic-Gated Bispecific Modelling Substantially Expands Target Opportunities

Using the CipherPro logic-gated modelling framework to predict complementary expression patterns, Promatix evaluated 165,025 possible bispecific combinations derived from the 575 tumour-expressed surface proteins identified in TxPro. Logic-gated modelling uses simple Boolean rules like AND or OR to combine multiple inputs and control the final output.

Application of the integrated TxPro + CipherPro platform revealed a marked increase in predicted tumour-selective opportunities across multiple selection criteria. Using a DE threshold greater than 10-fold with AND-gated modelling, 2,164 bispecific combinations were identified compared to only 24 monospecific targets. Even under more stringent expression and normal-tissue filters, the bispecific number remained substantial. Both AND- and OR-gated binding modes were shown to dramatically improve the number of selective targeting opportunities: AND-gated designs delivered the strongest predicted gains in tumour selectivity, while OR-gated strategies supported broader tumour coverage, particularly in heterogeneous disease settings.

Experimental Validation Supports Predictive Power of the Promatix Platform

The TxPro + CipherPro platform identified EGFR × EphA2 as a compelling AND-gated bispecific candidate based on expression patterns across tumour and normal tissues. Minimal overlap of the two targets was observed in normal tissues, while strong tumour co-expression was confirmed experimentally using immunofluorescence staining on a patient colorectal tumour biopsy as well as flow cytometry in colon cancer patient-derived xenograft lines. These results demonstrate the feasibility of selective dual-target engagement and show how computational prediction can be translated into biologically validated bispecific target selection. The EGFR × EphA2 programme, PBS293, is in development for metastatic colorectal cancer and is designed to address a broader patient population, independent of RAS/BRAF mutation status and including right-sided colorectal tumours, for which current treatments, including monoclonal antibodies targeting EGFR, such as cetuximab, are ineffective.

“As the ADC field continues to evolve, expanding the universe of tumour-selective targets will be essential to sustaining innovation,” said Dr. Roy Pettipher, Chief Scientific Officer of Promatix. “Our data demonstrate that logic-gated bispecific discovery provides a viable and scalable path toward safer and more effective therapies across many cancer indications. The platform doesn’t just predict new bispecific targets; it identifies combinations that work biologically and can be validated experimentally. Importantly, this approach has already been used to identify a promising ADC candidate, our lead programme, PBS293, targeting EGFR and EphA2 for the treatment of colorectal cancer, demonstrating how predictive discovery can translate into actionable therapeutic programmes.”

About Promatix Biosciences Ltd

Promatix is a UK-based oncology drug discovery and development company developing next-generation bispecific antibody–drug conjugates (ADCs) through rational, data-driven cis-target pairing.

The Company’s approach centres on identifying optimal combinations of cancer surface markers for cis-bispecific “AND-gate” targeting, in which strong binding, payload delivery and uptake occur only when two distinct antigens are present on the same tumour cell. This dual-antigen engagement is designed to enhance tumour selectivity. By exploiting hybrid avidity, Promatix aims to reduce on-target off-tumour toxicity and expand the range of targets that can be addressed with ADCs.

At the core of the platform is TxPro, a comprehensive tumour surface proteomics database covering membrane proteins across multiple cancer types. TxPro is supported by proprietary computational analytics (CipherPro) to systematically mine tumour-selective antigen pairs, affinity-engineering capabilities (AviPro) to optimise bispecific engagement, and a modular functional validation framework for rapid evaluation and lead selection (BiPro).

Promatix is developing a pipeline of novel bispecific ADCs in colorectal cancer and additional solid tumour indications.

For more information, visit www.pro-matix.com and follow us on LinkedIn.

CONTACT INFORMATION:

Promatix Biosciences Ltd
info@promatix.com

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promatix@mc-services.eu

Dr. Graeme Martin

Executive Chairman

Graeme is a Pharmaceutical industry veteran and life-science venture capitalist with over three decades of innovative therapeutic R&D experience with Wellcome, GlaxoWellcome, Roche and Takeda that produced 4 IND submissions. He was the preclinical lead for the development of Zomig for migraine acute treatment. He also has two decades of life-science investment experience, having built and led the corporate venture unit of Takeda Pharmaceutical Company.  He currently serves strategic advisory and Board roles with private stage biotechnology companies and life science venture capital funds (ALSA Ventures; Harrington Discovery Institute) in the UK and USA, and was Chair of DJS Antibodies, acquired by AbbVie in 2022.

Bruce Goldsmith

Advisor, Operating Partner, ALSA Ventures

Bruce has a strong background in Pharma and Biotech leadership over the past 25 years. He held progressively senior roles at Pharma and Biotech companies, including Johnson & Johnson, Allos Therapeutics and Lycera Corp. Following this experience, he joined Deerfield Healthcare as a Venture Partner and led a new company creation as CEO. He then joined Passage Bio as CEO leading an IPO and advancing four programs through IND. Throughout his career Bruce has led business development deals, strategy and operations. Bruce holds a PhD in Biology and an MBA.

Richard Onyett

Business Development Director

Richard Onyett, Business Development Director has worked with Promatix since Autumn 2025 to lead outreach with regard to commercial partnerships and licensing of technology and/or product assets. Prior to joining Promatix he was V.P. Business Development at ADC Therapeutics from 2012 until late 2024. Prior to that he served as Head of Business Development for Spirogen Ltd 2011 to 2012 and Oxagen Limited from 2006 to 2011. Richard led the business development programme at KuDOS Limited which resulted in the sale of the company to AstraZeneca (2001-2006). Prior to this Richard served as Head of Business and Corporate at several biotech companies and for two major pharma companies in marketing and business development roles.

Lorna Collings

CFO

Lorna has more than twenty years of experience in private equity and venture capital with roles at EQT, Hermes GPE, Citco, Coller Capital, Ariadne Capital, Actis and BancBoston Capital. She holds a BA in Applied Psychology and is registered with the Chartered Institute of Management Accountants (ACMA).

Dr. Robert Balfour

Non-Executive Director

Robert has a successful background in venture capital and Big Pharma, with companies such as GSK and Eli Lilly. He is a passionate start-up entrepeneur with experience in university technology transfer. Robert holds a BSc in Physiology and a PhD in Neurophysiology.

Alek Safarian

Non-Executive Director

Alek has a diverse background in drug development spanning more than thirty years. Trained as a pharmacist, he worked in regulatory affairs and clinical research roles for European and US-based multinational pharmaceutical companies in Australia, with responsibility across the Asia-Pacific. He subsequently founded Novotech, a Sydney-based contract research organisation working with hundreds of clinical stage biotech companies over a twenty-one year period. Alek holds a BPharm and an MBA from the University of Sydney.

Dr. Daniel Holdbrook

Principal Data Scientist

Daniel currently leads efforts in applying data analytics, proteomics, and computational modelling to target identification and drug discovery. He has 16 years of experience in these areas and has worked at prestigious research institutions in the UK and Singapore. Additionally, he has extensive experience in developing ‘omics’ solutions within biotech start-up companies. Daniel holds a BSc in Biochemistry, an MSc in Bioinformatics, and a PhD in Computational Biochemistry.

Dr. Katherine Vousden

Vice President, Research

Katherine is a proven leader in biologics discovery, with 25 years experience across biotech, biopharm and service organisations where she has built an extensive portfolio of candidate biologics in multiple disease areas. She has had significant strategic, project and group leadership roles at MedImmune/ AstraZeneca, Charles River and most recently held the position of site lead for AbCellera’s UK-based laboratory. Katherine holds a PhD in Genetics from the University of Leicester.

Dr. Shan Vinall

Project Manager

Shan has over 20 years biotech experience in drug discovery and development. She has previously held project management positions at Atopix and Oxagen where she gained extensive experience in the management of outsourced preclinical and clinical development studies, documentation, project planning and budgeting. Shan holds a BSc in Biochemistry and a PhD in Intracellular signalling.

Dr. Roy Pettipher

CSO

Roy is a co-founder of Promatix with over 30 years of industry experience in anti-inflammatory and oncology drug discovery and development. He is the founder and CSO at Orca Pharmaceuticals, a program licensed to AstraZeneca and has previously served as the research director at Atopix, which was sold to Chiesi in in 2016. He has also held senior R&D executive positions in biotech (Oxagen & AdoRx)and Pharma(Pfizer & Wellcome). Roy holds a PhD in Pharmacology from the University of London.

Dr. Mark Edwards

CTO

Mark is a co-founder of Promatix and has a 40-year background in applying protein engineering to drug discovery and development. He previously held positions at Searle, PA Technology, British Biotech and was the founding Director at Oxagen. Prior to joining Promatix, he was as a consultant working with start-ups on a wide range of products ranging from antibody therapies to antibiotic resistance and vaccines. He holds a BA in Biochemistry and DPhil in bacterial gene expression from Oxford.

Dr. Mick Hunter

CEO

Mick is a co-founder of Promatix and has over 40 years biotech experience spanning concept to clinic for multiple IND candidates across a range of therapeutic indications including management of process development and GMP biologics production. He has held senior R&D executive positions at GD Searle, Atopix, Oxagen, British Biotech. He was the CSO of Atopix, sold to Chiesi in 2016, and founder and CEO of Orca Pharmaceuticals, whose ROR gamma program was licensed to AstraZeneca and to Brickell Biotech. More recently Mick was Entrepreneur in Residence at Evotec. He holds a PhD in Molecular Biology and Genetics from the University of Nottingham.