Antibody Supply

Supply4g – Polyclonal Antibody Supply

Polyclonal antibodies play a vital role in both research and clinical applications due to their ability to recognise multiple epitopes on a single antigen. This multi-epitope recognition enhances their sensitivity and makes them particularly effective in detecting low-abundance targets, even in complex biological samples.

SupplyEpitope Mapping

In the race to engineer high-affinity, highly selective antibodies, understanding the precise interaction between antibody and antigen is no longer a luxury—it’s a necessity. Epitope mapping using cross-linking mass spectrometry (XL-MS) offers a powerful, high-resolution approach to define these critical interfaces with speed and confidence.

SupplyAntibody Characterization

Fusion Antibodies provides a robust portfolio of antibody characterisation services designed to generate high-quality data that supports confident decision-making across discovery, development, and translation. Our services are available as stand-alone studies or fully integrated with antibody generation, engineering, and reformatting programmes.

SupplyCell Line Development

At Fusion Antibodies, we bring extensive experience with a variety of mammalian expression systems to support your clinical development with confidence and flexibility. We specialize in the rapid generation of well-characterized, regulatory-compliant cell lines with strong clinical track records.

SupplyMammalian Transient Protein Expression

Fusion Antibodies delivers expert mammalian transient gene expression (TGE) for rapid, scalable protein generation. Our platform supports assay development, antibody screening, structural biology, and preclinical studies—with speed, precision, and reproducibility.

EngineeringRAMP® Rational Affinity Maturation Platform

Fusion’s affinity maturation platform combines natural somatic hypermutation with advanced structural modelling to introduce targeted mutations and evaluate molecular interactions, resulting in antibody variants with enhanced binding affinity and improved stability.

EngineeringAntibody Developability

At Fusion Antibodies, we recognize that the biophysical and biochemical properties of antibodies critically influence the safety, efficacy, and manufacturability of biologic therapeutics. That’s why we begin every project with a forward-thinking approach—leveraging our deep expertise in sequence optimization to streamline your path to the clinic.

EngineeringFc Engineering for Function, Stability, and Clinical Success

Enhance effector function, extend half-life or silence activity with Fc region modifications designed by our expert team.

EngineeringWhat Are Bispecific Antibodies, and Why Do They Matter?

Bispecific antibodies are engineered therapeutic molecules designed to simultaneously bind two distinct antigens or epitopes. This dual targeting capability enables powerful and differentiated mechanisms of action, including immune cell redirection, enhanced tumor selectivity, dual checkpoint inhibition, and coordinated modulation of multiple disease pathways.

EngineeringReformatting Antibodies for Precision and Performance

Explore the full spectrum of antibody reformatting techniques—from chimerisation to Multivalent Variants; tailored for research, diagnostics, and therapeutics.

EngineeringAntibody Species Conversion

Antibody species conversion is a critical step when transitioning therapeutic or diagnostic antibodies originally developed in human, mouse or rabbit into veterinary formats suitable for cat, dog, horse, pig or cattle. This process ensures compatibility with the target species’ immune system, minimizing immunogenicity and enhancing efficacy.

EngineeringAntibody Humanization Services Using Humanization CDRx®

Fusion Antibodies provides antibody humanization services that help biotechnology and pharmaceutical companies reduce immunogenicity while preserving the affinity, specificity and functionality of their lead antibodies. Since 2012, we have completed more than 290 antibody humanization projects while 100% successfully maintaining function and affinity and no reported immunogenicity issues following our humanization strategy.

DiscoveryOptiPhage® Next-Gen Phage Display Library

OptiPhage® from Fusion Antibodies is a cutting-edge, proprietary single-chain variable fragment (scFv) library engineered specifically for phage display technology, expanding upon the successful OptiMAL® platform previously optimized for mammalian display. OptiPhage®: Broadening Antibody Discovery with Enhanced scFv Library

DiscoveryAI/ML-ab™ de novo Antibody Discovery

Traditional methods—animal immunization and display technologies— can be limited by immunodominance and physical library size. This might mean missing rare, high-affinity binders. Similarly, the antigen may be difficult to produce, toxic or not available. AI/ML-ab™ breaks through these constraints with virtual screening of libraries millions of times larger than conventional platforms, delivering focused, high-potential candidates for wet-lab validation.

DiscoveryOptiMAL® Mammalian Display

OptiMAL® is Fusion’s next-generation mammalian display platform—engineered to deliver full-length human IgG antibodies in just 3–4 months. By negating the need for animal immunization, humanization, and reformatting, OptiMAL® accelerates discovery while enhancing developability. Our proprietary intelligent library design, based on natural human mutations, enables identification of high-affinity, low-immunogenicity binders ready for pre-clinical study.

DiscoveryRabbit B-Cell Cloning Robust Methodology for Antibody Discovery

B-cell cloning is a method used to discover and develop therapeutic antibodies. Instead of relying on hybridoma technology, B-cell cloning isolates antibody-producing B-lymphocytes directly from the animal and then recovers the genetic information encoding the antibodies they naturally produce.

DiscoveryMouse Hybridoma for Monoclonal Antibody Discovery

Mouse Hybridoma remains one of the most established and reliable technologies for monoclonal antibody discovery, particularly when high-specificity antibodies are required for research, diagnostic and therapeutic applications. At Fusion Antibodies, mouse hybridoma forms an integral part of our broader antibody discovery and engineering services, supporting programmes from target assessment through to recombinant antibody development and humanisation.

DiscoveryAntigen Design Services

Successful antibody discovery begins with effective antigen design. The quality, format and biological relevance of an antigen directly influence antibody specificity, epitope diversity, affinity and downstream developability. Fusion Antibodies provides custom antigen design services that support therapeutic antibody discovery, antibody engineering and biologics development from target evaluation through to lead optimisation.

DiscoveryAntibody Discovery Services

Accelerate antibody discovery with Fusion Antibodies’ integrated, multi-platform CRO workflow designed to deliver high-quality monoclonal antibodies, recombinant antibodies, and therapeutic leads for preclinical and translational drug development.

SupplyRUO Stable Expression

Reliable expression, analytics and supply for confident development decisions.

SupplyAntibody Supply

Reliable expression, analytics and supply for confident development decisions.

EngineeringFLAME™

Smart molecular design for stronger, safer, manufacturable antibody candidates.

EngineeringADC Design

Smart molecular design for stronger, safer, manufacturable antibody candidates.

EngineeringAntibody Engineering

Smart molecular design for stronger, safer, manufacturable antibody candidates.

ApplicationsAntibody Development for Animal Health

Veterinary medicine faces unique hurdles in antibody development—from species compatibility to scale-up for large animals. Fusion Antibodies offers specialized solutions to overcome these barriers and accelerate therapeutic and diagnostic innovation in animal health.

ApplicationsDiagnostic Antibody Development

Developing diagnostic antibodies demands more than just binding activity. It requires precision, reproducibility, and platform compatibility. Common challenges include selecting accessible, diagnostically relevant epitopes, avoiding cross-reactivity, and ensuring consistent performance across batches and formats. Fusion’s approach is built to overcome these hurdles.

ApplicationsHuman Therapeutics

Fusion provides comprehensive antibody development services from discovery and engineering to supply, designed to accelerate preclinical research for drug developers. Since 2001, Fusion has successfully completed over 1,800 antibody development projects, advancing 12 antibodies to the clinic, with many more currently in preclinical testing.

CompanyAbout Fusion Antibodies

Fusion Antibodies plc is a publicly listed contract research organization (LSE: FAB) specializing in the early pre-clinical development of therapeutic and diagnostic antibodies. Founded in 2001 and headquartered in Belfast, Northern Ireland (United Kingdom), we operate ten state-of-the-art laboratories (>2,000m2) that integrate both in silico and wet-lab capabilities, enabling us to deliver fully integrated, end-to-end antibody development solutions.

CompanyTestimonials

Behind every programme is a team with something important at stake. We are proud to be trusted with the difficult science—and remembered for how we worked together.

CompanyEvents

Join our scientists and commercial team at conferences, focused webinars and partnering sessions around the world.

CompanyCareers

Join a collaborative team combining deep scientific expertise with the pace, ownership and visible impact of a specialist biotech.

CompanyDisclaimer

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CompanyAccessibility Statement

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CompanyModern Slavery Statement

Fusion Antibodies PLC (“Fusion Antibodies”, “we”, “our”, “us”) is committed to acting ethically and with integrity in all our business activities and relationships. We oppose modern slavery and human trafficking in all its forms and take steps to ensure that it does not take place in our organisation or in our supply chains. 1. Our […]

CompanyCookie Policy (UK)

This Cookie Policy was last updated on September 25, 2025 and applies to citizens and legal permanent residents of the United Kingdom. 1. Introduction Our website, https://fusion-live.leviathanstudiosltd.com/cms (hereinafter: “the website”) uses cookies and other related technologies (for convenience all technologies are referred to as “cookies”). Cookies are also placed by third parties we have engaged. […]

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CompanyPrivacy Policy

By visiting our website, you are accepting the practices described in this Privacy Policy. 1. Overview Fusion Antibodies plc is concerned about its users and the protection of their private information. Accordingly, Fusion Antibodies has created this Privacy Policy (the “Policy”) that applies to the services offered by Fusion Antibodies, including this website (the “Services”). […]

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Scientific thinking, programme stories and company updates from across Fusion.

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CompanyContact Us

Tell us where you are in your antibody development journey and our team will help define the next meaningful step.

newsDesigning evidence that survives the next stage

Connect target biology, assay design and development decisions from the outset.

newsStarting with the right biological question

Explore the scientific context, practical decisions and lessons that help antibody programmes move forward with confidence.

newsAnimal Health Summit

Fusion will be attending 1-1 meetings at the Animal Health Summit to discuss partnerships and opportunities for engineering, Bi-specifics and Species switching in antibodies.

newsImmuno-Oncology Summit US 2025

Fusion Representatives will be attending the 13th Annual Immuno-Oncology Summit. Presenting Posters on OptiMAL™, Mammalian Display & Rational In-Silico Developability (Ab-ility™)

newsR&D update: Mammalian Display service

Fusion Antibodies release an R&D update: Mammalian Display service OptiMAL®

newsOne size fits all: A bispecific antigen toolkit for antibody discovery and screening

Fusion Antibodies have harnessed a bispecific antigen toolkit for antibody discovery and screening.

newsAppointment of Chief Executive Officer

Fusion Antibodies plc announces the appointment of Dr Adrian Kinkaid as Chief Executive Officer.

newsFusion Antibodies plc Announces Formation of New Scientific Advisory Panel

World-renowned experts in the fields of antibody engineering Matthew Baker Ph.D., Professor Terry Rabbitts, and Professor Charlotte Deane to join Fusion Antibodies Scientific Advisory Panel

newsOmicron introduced to Fusion Antibodies R&D Catalogue

Fusion Antibodies has decided to include Omicron RBD, alongside the alpha, beta, gamma and delta+ RBD variants, in its development programme with the aim of producing virus-neutralising antibodies.

newsFusion Antibodies RAMPs Up Collaboration Success

New $1.83 million R&D project win for Fusion Antibodies reinforces its position as one of the leading providers of early-stage antibody discovery and engineering services.

newsFusion Antibodies partners with Eurofins Discovery to support innovative preclinical drug discovery research

Fusion Antibodies and Eurofins Discovery sign co-marketing agreement to support timely and cost-effective development of innovative products for the benefit of global healthcare

newsSupporting Indian Biotherapeutic Companies with Antibody Development

Fusion Antibodies, pre-clinical antibody discovery and development experts and BioTickle, their exclusive distributor in India, are providing local biopharmaceutical organisations with access to invaluable unique biopharmaceutical development capabilities.

newsFusion Antibodies proud to support ‘State of the Art’ project

NI Science Festival, in conjunction with Linen Biennale recently rolled out the virtual red carpet to premier Dr Anthony O’Kane’s ‘Translating Linen.’

newsFusion Antibodies awarded Platinum Level Innovator Status by Innovate NI

Fusion Antibodies is delighted to be recognised as a Platinum Level Innovator in the Innovate NI Innovation Accreditation programme from the Department for the Economy.

newsFusion Antibodies and Queen’s University Belfast Receive Grant to Boost R&D for COVID-19 Antibodies

Fusion Antibodies and Queen’s University Belfast Receive £453,000 grant from Invest Northern Ireland to Boost Research and Development for COVID-19 Antibodies

news200 Reasons to Celebrate!

Fusion Antibodies are celebrating their 200th Antibody Humanization project, cementing our place as a leading CRO in antibody engineering services.

newsDr McGirr named ‘Future Innovator’ Winner at KTP Best of the Best Awards

Dr Leona McGirr of Fusion Antibodies has received a top honour at the annual celebration of the most outstanding Knowledge Transfer Partnership (KTP) Projects.

newsFusion Antibodies collaborates with QUB Led Project in Multi-Million Pound Funding Bid

A Belfast-based bid led by Queens University Belfast (QUB), is the only bid from Northern Ireland to be selected for the next stage of the UK Research and Innovation’s Strength in Places Fund (SIPF).

newsFusion Antibodies make key Covid-19 Reagents available

As part of our efforts to combat the Covid-19 pandemic, We have designed and expressed a panel of unique recombinant protein antigens to assist in the search for a neutralising therapeutic antibody against SARS-CoV 2.

newsFusion Antibodies partner with BioTickle to deliver antibody development services in India

Fusion Antibodies have named BioTickle as their exclusive distributor in India to provide access to proprietary antibody discovery, engineering and cell line development technologies.

newsResearch Alliance with Queen’s University Belfast

A new research alliance has been formed to seek new therapeutic and diagnostic approaches to help in the global fight against the coronavirus pandemic.

newsFusion Antibodies Collaborates with Queen’s University on Knowledge Transfer Partnership Programme

The new programme will allow for the development of an innovative software solution for the design of antibody libraries.

newsFusion Antibodies form strategic collaboration with E2DG to provide end-to-end service for oncology drug discovery companies.

The two companies will work together to deliver a seamless service offering for clients from discovery to manufacturing and PoC preclinical and phase I & II design and execution.

newsFusion Antibodies partner with Erada to develop ground breaking Malaria diagnostic

Ground Breaking New Saliva Diagnostic Test Set to Help Eliminate Malaria.

newsFusion Antibodies to collaborate with Analytics Engines

Fusion Antibodies plc, experts in antibody engineering and Analytics Engines, an advanced data analytics company, have announced a strategic collaboration to incorporate machine learning (ML) and artificial intelligence (AI) into Fusion Antibodies’ CDRx™ humanization platform.

newsFusion Antibodies announces partnership with Protein Alternatives

Fusion Antibodies announces partnership with Protein Alternatives to develop world class humanized antibodies for therapeutic development Fusion Antibodies plc, a UK-based contract research organisation and Protein Alternatives, a biotechnological organisation, are pleased…

newsFunding for Queen’s pancreatic cancer drug research in collaboration with Fusion Antibodies

Queen’s University Belfast researchers at the Centre for Cancer Research and Cell Biology (CCRCB) alongside Fusion Antibodies plc have secured a prestigious Medical Research Council (MRC) award to develop a new antibody drug for the treatment of pancreatic cancer.

newsAlliance between Fusion Antibodies and Nb Health Laboratory

Fusion Antibodies, a UK-based contract research organisation and NB Health Laboratory (NBHL), a Japan-based biotechnology company specialising in GPCR-targeting drug discovery, are entering an alliance for a research and licence agreement in…

newsFusion Antibodies and Bizcom Japan continue to strengthen ties.

Fusion Antibodies and BizCom Japan, a privately-held Japan-based trading and consulting company, continue to strengthen ties with Fusion’s Director Paul Kerr attending BioJapan 2016 with BizCom Japan’s Director Hiroyasu Nakatani. BizCom Japan…

newsFusion Antibodies announces Cell Line Development collaboration with Celonic

Fusion Antibodies are happy to announce we have entered into a partnership with Swiss contract manufacturing organisation Celonic AG to collaborate on the development of high yield stable cell lines. The deal…

newsFusion Antibodies announces collaboration with Aerpio Therapeutics for second Antibody Humanization project

Fusion Antibodies are pleased to announce a second collaboration with Aerpio Therapeutics to apply our CDRx Antibody Humanization platform to Aerpio’s Mouse Monoclonal Antibody. Fusion Antibodies Ltd are excited to announce our…

newsWhy is Antibody Humanization still important in the 21st century?

Monoclonal antibodies, or mAbs, have become a crucial tool and are used for both diagnostic and medical applications. This article will explain the importance of mAbs and antibody humanization techniques involved. If…

expert insightsKeeping developability in view from day one

Build the evidence package around the molecule you ultimately need to develop.

expert insightsWhen difficult targets need a different route

A practical look at the choices that can unlock a challenging antibody programme.

expert insightsOvercoming obstacles on the path to the clinic

Finding a high-affinity antibody that binds to your target is only the first step. Not every antibody has what it takes to become a licensed medicine.

expert insightsHumanization – Much more than a handle turning exercise

We explore best practice in antibody humanization to deliver the best outcome for your molecule. Download our latest antibody humanization publication.

expert insightsFusion Antibodies: Quality By Design

Selecting a therapeutic antibody that will become commercially successful is often a huge gamble, with candidates potentially failing at any stage of development.

expert insightsPiloting successful transient protein expression

Waving goodbye to antibody engineering and moving your lead candidates into transient protein expression is a big milestone in therapeutic antibody development. Wise developers budget a few weeks into their timelines to invest in a small-scale pilot project before scaling up.

expert insightsHarnessing the rabbit antibody repertoire

Rabbit derived monoclonal antibodies have become important starting points for therapeutic molecules. However, humanization of these antibodies can present challenges as traditional techniques have been concomitant with affinity loss and other issues.

expert insightsBispecifics – Expanding the potential of immunotherapies

With a quality by design approach, we employ our in silico and protein engineering expertise to design and optimize an engineering program ideal for an antibody candidate, shaped with the endpoint in mind.

expert insightsStepping outside of the CDR to create naturalised libraries and humanized antibodies

With their high specificity, efficacy and safety profiles, it’s no wonder that antibodies have become the biggest selling drugs in recent years.

expert insightsHumanized antibody innovation: Top tips for outsourcing

Dr Richard Buick, CTO of Fusion Antibodies explains what he believes to be the top criteria to consider when selecting a humanization outsourcing partner

expert insightsStarting your journey into manufacturing – choosing a cell line development provider

One of the biggest decisions which any company developing biological medicines makes is to move forward to the manufacture of their product.

expert insightsTherapeutic antibodies: the scale of the manufacturing challenge

The most effective medicines in the world are of limited value if they can’t be produced in bulk, and at a reasonable cost. Therapeutic antibodies take years to develop. Without good oversight, each stage of development risks operating in a vacuum…

expert insightsThe challenges of phage display for affinity maturation

At Fusion Antibodies, our rational affinity maturation platform sidesteps most of the issues with phage display. Our rationally designed in silico libraries are magnitudes larger than phage libraries, with around 10^25 variants.

expert insightsMaking your best antibody better

RAMP™ up your chances of getting to the clinic.

expert insightsIn silico – the future of antibody development

Learn more about how in silico technology accelerates antibody design and development, which reduces costs.

case studiesBuilding better programmes through partnership

The strongest programmes combine specialist capability with open, direct collaboration.

case studiesThe value of transparent scientific handovers

Clear decisions and joined-up data make every next experiment more useful.

case studiesA Novel Approach to Affinity Maturation

Read our short case study about the results we have delivered with Cathepsin S, using our unique affinity maturation platform RAMP™

case studiesHumanized Antibody JF5 detects Aspergillus

Towards translational ImmunoPET/MR imaging of invasive Pulmonary Aspergillosis: The Humanized Monoclonal Antibody JF5 detects Aspergillus Lung Infections in Vivo

case studiesPotential biomarkers for bladder and colon cancer

Non-phosphorylated and Phosphorylated Signal Transduction Peptide (STP) of Tissue Factor (TF) in Urine are Potential Biomarkers for Bladder and Colon Cancer.

careersFacilities Manager

Reporting to the Operations Manager, the role of the Facilities Manager will be responsible for the upkeep and maintenance of laboratories & buildings in line with company requirements, as well as health and safety. The candidate is expected to lead, develop, implement and sustain industry standard health and safety (and environmental) best practices throughout Fusion.

careersProtein Characterisation Senior Scientist

Reporting to the Operations Manager, you will independently design and develop biophysical assays, in a range of formats, suitable for Drug Discovery across a wide range of target class and modalities.

careersLaboratory Technician

This is an entry-level position, the role of Laboratory Technician will be responsible for supporting the delivery of Production projects. The successful candidate should have a basic laboratory knowledge.

careersProduction Scientist

This is an entry level position, reporting to the Production Team Leader, the role of Production Scientist will be responsible for delivering production projects on behalf of clients. The successful candidate should have a basic knowledge of protein expression, purification and characterization, knowledge of general cell culture techniques and transfection of mammalian cell lines.

careersTeam Leader Antibody Engineering

The role of Antibody Engineering Team Leader will be responsible for all aspects of protein engineering, particularly monoclonal antibody drugs. This will include multi-specific antibody design, affinity maturation, protein-protein docking, developability analysis, humanization and antigen design. The team leader will manage a team of scientists while acting as a liaison with other business units.

careersR&D Team Leader

Reporting to the R&D Director the role of R&D Team Leader will be responsible for developing and executing new service and product development and works with the commercialisation team to bring these products/services to market.

careersCommercial Operations Administrator

Serving within the Commercial Department, the Commercial Operations Administrator is responsible for supporting the general operations of the commercial team as well as gathering and curating key data to help Fusion Antibodies gain valuable insights and inform decision-making.

careersBusiness Development Manager

Reporting to the Commercial Senior Director, the role of Business Development Manager will be accountable for key account management activities as well as proactive new client engagement.

careersR&D Scientist

This position is no longer accepting applicants.

careersMarketing Communications Executive

Reporting to the Marketing Director, the role of Marketing Communications Executive will run point on all day to day marketing activity covering everything from event co-ordination to content development.

careersCLD Team Leader

This position is now closed.

careers2 X Technical Production Scientists

THIS POSITIION IS NOW CLOSED.

careersLab Technician

THIS POSITION IS NOW CLOSED.

PartneringMeet Fusion: one-to-one partnering day

Book focused time with our discovery, engineering and supply specialists around your next programme challenge.

ConferenceAntibody engineering & development forum

Meet our scientists to discuss humanization, developability, Fc engineering and formats built for the clinic.

WebinarFunction-first antibody discovery campaign

A practical session on connecting target biology, screening strategy and lead selection from the outset.

Past eventVet Health Global – 2025

Past eventBIO International Convention 2025

Past eventAntibody Engineering & Therapeutics – Europe 2025

Past eventDiscovery on Target 2023

Past eventBIO International 2023

Past eventAnglo Nordic Life Science Conference 2023

Past eventBIO Korea 2023

Past eventBio Integrates 2023

Past eventBIO Europe Spring 2023

Past eventAntibody Engineering & Therapeutics USA

Past eventhubXchange – West Coast Xchange

Past eventDrug Discovery 2022

Past event17th Drug Discovery Innovation Programme

Past eventDiscovery on Target 2022

Past eventProtein Sciences in Drug Discovery- ELRIG

Past eventAntibody Industrial Symposium 2022

Past eventBIO International Convention

Past eventAntibody Engineering & Therapeutics Europe

Past eventhubXchange Boston

Past eventPEGS Boston 2022

What can we help you find?

Antibody Supply

Built around your programme

A connected workflow

Tell us what you’re working on.

Antibody Supply

Built around your programme

A connected workflow

Connected expertise,without the hand-offs.

4g – Polyclonal Antibody Supply

Epitope Mapping

Antibody Characterization

Connected expertise,
without the hand-offs.