ADC Overview
Comprehensive ADC development and manufacturing solutions, led by a highly experienced team
Antibody-drug conjugates, or ADCs, are highly targeted therapies often used in cancer treatment. Because of their precise targeting capabilities and the demand for novel oncology therapeutics, the global ADC market continues to grow at a rapid pace. An experienced partner can make all the difference when it comes to developing these complex molecules to deliver effective, targeted cancer therapies.
At Sterling, with more than ten years’ dedicated experience supporting ADC discovery, development and clinical manufacturing, our specialist bioconjugation team works in close collaboration with our clients to proactively overcome challenges. In addition, our team has experience working with an extensive range of antibodies, as well as other targeting molecules, and different classes of payload; selecting the right linker to compliment both payload and antibody.
Keep reading for an overview of our ADC services and to learn how our purpose-built facilities, flexible approach and specialised teams position us as an ideal partner for even the most complex ADC project requirements.
A look at Sterling Pharma Solutions’ comprehensive ADC services
As a partnership development and manufacturing organisation (PDMO®), we aim to be so much more than a traditional contract development and manufacturing organisation (CDMO). We are committed to working with you closely to develop efficient processes, maximise effectiveness and ensure scalable and repeatable results, together.
Let’s take a closer look at how we can support your ADC project from discovery to clinical manufacturing.
Our team provides the expertise, equipment and capabilities needed to support customised early stage ADC development services.
Our experience working with a variety of targeting molecules, linkers, and payloads enables us to support robust ADC proof of concept, to design and develop a tailored ADC that meets your specific project objectives. In addition, we are focused on helping our customers optimise drug-to-antibody ratio (DAR), which directly impacts the ADC’s efficacy, safety, and pharmacokinetic properties.
In addition, we provide expertise spanning various conjugation approaches, including cysteine, lysine, and enzymatic.
We provide comprehensive analytical services to support high-quality ADC development and manufacturing. Our analytical approach allows us to gain a full understanding of potency and other important ADC properties, while ensuring quality and regulatory compliance at every stage of development.
Our analytical capabilities for ADCs include:
- Raw material, in-process, and release tests
- Analytical method development aligned with ICH guidance
- Lot release and stability testing for drug substances and drug products
- Environmental monitoring
- Cleaning methods and monitoring
To support robust analytical method development, we offer expertise across a variety of testing methods, including:
- Chromatography
- Cell-based potency assays
- Immunoassays
- Spectrophotometry
- Mass spectrometry
- Microbiology
- Residual solvents
The success of an ADC depends on the intelligent design of its linker payload, which is responsible for delivering and activating the therapeutic agent within cancerous cells. Our Deeside, UK and Wisconsin, US sites provide containment expertise to support high-quality linker-payload synthesis.
Our team has experience with a number of different linker types and technologies, allowing us to select the approach that is best suited to your programme in order to increase stability, control premature drug release and influence an ADC’s efficacy, safety, and pharmacokinetic properties.
Our ability to work with numerous payloads while ensuring appropriate containment allows us to support a range of ADC project requirements, including more common toxic payloads such as Exatecans, Auristatins and PBDs to newer modalities such as degraders, metal chelators and steroids.
Mass spectrometry, which determines the molecular weight of charged ions to support identification, characterisation, and quantification, is a particularly useful analytical method in the development and manufacture of ADCs. At Sterling, we provide mass spectrometry expertise to support:
- Characterisation and DAR of lysine or cysteine-linked ADCs
- Subunit characterisation of proteins and ADCs
- Peptide mapping of ADCs and proteins
- Disulfide bond confirmation
- Plasma stability of ADCs
Read more about our mass spectrometry services or discover how mass spectrometry can be leveraged to measure ADC stability in plasma and serum.
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Our Deeside facility is certified to support cGMP manufacturing for clinical and preclinical supply of ADCs up to the multi-kilogram scale. Our facility includes both Grade C and Grade D manufacturing environments that are suitable for a range of batch sizes and custom containment measures. Our manufacturing suites include:
- Disposable canopy isolator
- Separate buffer preparation area
- Conjugation up to 75L reactive volume
- Flexible tangential flow filtration (TFF) systems
- Chromatography column up to 20L
Read more about our ADC manufacturing capabilities or take our virtual tour to explore the GMP manufacturing suites at our Deeside facility.
Challenges in ADC development and manufacturing, and how we overcome them
ADCs are complex, and developing safe and effective therapeutics comes with a variety of challenges. Here’s how we overcome some of the most common hurdles associated with developing and manufacturing ADCs while ensuring quality and compliance.
- Linker selection – we have experience working with both cleavable and non-cleavable linkers, as well as different tethers, polarity, triggers, and immolation methods, to ensure both safety and efficacy.
- Payload selection and synthesis – with expertise spanning various cytotoxic payloads and a flexible containment approach, we help our customers to select and develop the best payload for their target.
- Drug-to-antibody ratio optimisation – our experience in ADC development, combined with support for a variety of conjugation methods, allows us to improve control and optimise DAR.
- Safe and effective process scale-up – we consider manufacturing implications from the start of an ADC project, ensuring appropriate containment measures and ongoing quality control.
- Regulatory compliance – our thorough approach to analytical method development for ADCs, paired with a deep understanding of regulatory requirements in key regions, enables us to help our clients prepare any necessary documentation and ensure ongoing compliance.
Our state-of-the-art facilities and capabilities for ADC development and manufacturing
Our dedicated bioconjugation facility is located in Deeside, Wales, UK.
Our team moved into the 6,500m2 facility in 2018, which is built for containment and designed specifically to accommodate highly potent bioconjugates with the safety of our people and the environment in mind.
The facility is specially designed to handle cytotoxic materials. This, combined with our extensive background in protein conjugate development, provides us with the capacity and capability required for even the most complex ADC requirements.
In addition, we can support linker-payload development from our Wisconsin, US, facility, which provides deep expertise in the development of high potency APIs and customised containment strategies, as well as our North Carolina, US and Newcastle, UK facilities.
Here’s a closer look at some of the specialised equipment we use to support ADC discovery, development, and manufacturing:
- Independently qualified glove box isolators, <2ng/m3
- AKTA chromatography systems
- Multiple vendor TFF systems with data logging
- Scalable reaction systems
- Agilent HPLCs with DAD and chilled autosamplers
- Sciex x500B QTOF mass spectrometer
- ProteinSimple Maurice for cIEF and CE-SDS
- UV/Vis spectrophotometry
- Multimodal plate readers for colorimetric and fluorescence assays
Why choose Sterling Pharma Solutions for your ADC projects?
With years of expertise and a proven track record in supporting numerous ADCs’ journeys to clinical trials, Sterling combines extensive bioconjugation knowledge with a partner-centered approach. From complex linker-payload synthesis to analytical support, we help you proactively anticipate and overcome challenges in ADC development while meeting your specific project objectives.
If you’re interested in exploring an ADC manufacturing or development programme with Sterling, get in touch with our team.
Looking for more information on ADCs?
Antibody-drug conjugates have three critical components. They combine a monoclonal antibody with an effector molecule using a linker. By harnessing the high selectivity of the antibody, paired with the high potency of the payload, ADCs can precisely target and kill cancerous cells.
As an ADC travels through the blood, the antibody recognises a tumour cell target and binds to an antigen on its surface. The linker breaks down inside the cell to release the payload, which kills the cancerous cell.
Because they directly target cancerous cells, ADCs minimise damage to surrounding healthy tissue compared to treatments like chemotherapy. This helps to reduce the harmful side effects that are commonly associated with cancer treatment and increases overall efficacy.
As of 2025, 15 ADCs have been commercially approved, with hundreds more in clinical development. ADCs are being used in the treatment of Hodgkin’s lymphoma, certain types of breast cancer, multiple myeloma, and other challenging cancers.
