Monoclonal Antibody Development Services
Monoclonal antibodies continue to play a central role in cancer treatment and immune-based therapeutics.
Our Monoclonal Antibody Development Services help sponsors characterize biological activity and therapeutic potential through:
These studies provide the evidence needed to advance the most promising antibody candidates.
Binding Affinity
Most binding assays rely on immobilization — but the moment you put your target on a surface, you risk changing its structure, masking epitopes, and generating misleading affinity data. Surface-based systems like Biacore are widely used, but they often struggle to accurately resolve high-affinity interactions and can mis-rank tight binders due to kinetic and rebinding artifacts.
We address this using the Sapidyne KinExA 4000 — a solution-phase technology that measures binding without perturbing equilibrium, using completely unmodified molecules in their native environment. Instead of measuring signal on a surface, KinExA quantifies the free (unbound) fraction at equilibrium, delivering highly accurate affinity values even in the picomolar to femtomolar range.
This becomes critical when working with high-affinity antibodies, bispecifics, or ADCs, where small differences define the winning candidate — differences that surface methods often cannot resolve. KinExA enables precise ranking of these molecules and works seamlessly in complex matrices such as serum, cell lysates, and biologics formulations.
Importantly, the system can also be configured to work with cells as binding partners, allowing measurement of interactions with cell-surface targets under near-physiological conditions — bridging the gap between biochemical affinity and biological relevance.
We complement this with ELISA for rapid screening and comparative profiling across large panels, ensuring speed early on and precision when it matters.
In short — we don’t rely on surface-driven signals. We measure binding the way it actually happens, so you can move forward with the right molecule.
Fc Functions
Effector functions are often the difference between a molecule that binds and a molecule that works. In immuno-oncology, Fc-driven mechanisms like ADCC, ADCP and CDC directly translate target engagement into tumor cell killing or clearance — and poor understanding here is a common reason why otherwise strong binders fail to deliver in vivo.
We evaluate these mechanisms using both flow cytometer-based assays and the IncuCyte S3, allowing you to capture not just endpoint activity but the kinetics of immune-mediated killing in real time. This dual approach helps distinguish fast-acting vs sustained responses, subtle potency differences, and donor-dependent variability — all critical for selecting the right candidate.
Our ADCC and ADCP assays are built around physiologically relevant systems, combining target cells with effector populations such as PBMCs/NK cells or macrophages, with flexible assay design depending on your program stage. We support both stable fluorescent labeling (GFP/mCherry) and industry-standard cytotoxicity/cell labeling dyes, enabling precise tracking of target cell fate, phagocytosis events, and immune cell engagement.
For CDC, we design assays tailored to your biology — including both cell-based complement-mediated cytotoxicity models and biochemical formats where appropriate, depending on whether you are assessing functional lysis or complement activation potential.
The goal is simple: move beyond “does it bind?” to “does it recruit the immune system effectively?” — and generate data that actually predicts in vivo performance.
Cell-based Potency Assays Fc Functions
Cell-based potency is where biology validates your molecule. In immuno-oncology, this almost always comes down to co-culture systems — where target cells and effector cells interact in a controlled but biologically meaningful environment. The challenge is not just to show activity, but to quantify true potency, mechanism, and kinetics in a system that reflects in vivo behavior.
We design and execute co-culture assays using both flow cytometer and the IncuCyte S3, giving you two complementary views of potency. Flow cytometry provides high-resolution, multiparametric endpoint data — enabling precise quantification of target cell killing, immune activation, and population dynamics. IncuCyte adds a different dimension — real-time visualization of killing, proliferation, and interaction kinetics, capturing how fast and how sustainably your molecule works.
Our co-culture systems are built with flexibility in mind:
- Tumor cells + PBMCs / NK cells / macrophages
- Engineered systems for bispecifics and T cell engagers
- Custom E:T ratios, donor variability, and assay conditions To ensure clear, quantifiable readouts, we support multiple labeling strategies
- Stable tagging of target cells (GFP, mCherry) for continuous tracking in live-cell assays
- Industry-standard fluorescent dyes for viability, apoptosis, and cytotoxicity measurements
- Multiplex labeling to distinguish effector vs target populations and monitor engagement
Bioassay –Purity, Potency & MOA
Bioassays are not just supportive experiments — they are regulatory-critical tools that define potency, consistency, and product quality. For biologics, especially antibodies, bispecifics and cell/gene therapies, a poorly designed bioassay can delay programs, fail validation, or compromise batch release.
We develop and validate bioassays in alignment with USP <1032> and USP <1033>, ensuring your assays are not only scientifically sound but fit-for-purpose for regulatory submissions and GMP environments.
Our approach starts with mechanism-driven assay design — linking the bioassay directly to the drug’s mode of action (e.g., receptor signaling, cytotoxicity, immune activation). We select the most appropriate platform — cell-based, reporter-based, binding, or functional — and optimize critical parameters such as dynamic range, sensitivity, and robustness.
We establish assays for:
- Potency determination (quantitative, stability-indicating)
- Purity and characterization support (orthogonal functional readouts)
- Batch release and comparability studies Validation is performed as per regulatory expectations, including:
- Accuracy, precision, linearity, and range
- Specificity and system suitability
- Robustness and intermediate precision
- Parallelism and relative potency models
Where required, assays are transferred into controlled environments with well-defined SOPs, reference standards, and acceptance criteria, ensuring reproducibility across batches and over time.
The outcome is a fully characterized, validated bioassay that stands up to regulatory scrutiny and reliably supports product release, comparability, and long-term program success.
