Lead Optimization
Lead optimization
Lead optimization is the stage where promising hit molecules or biological candidates are systematically refined into more potent, selective, and biologically well-characterised lead candidates. At ImmunitasBio, we combine functional immunology, mechanistic assays, and comparative profiling to generate the biological evidence needed to guide structure–activity relationship (SAR) decisions and candidate progression.
Our approach goes beyond measuring potency alone. We evaluate how candidate modifications influence target engagement, functional activity, selectivity, mechanism of action, and immune effector functions, helping identify candidates with the right balance of efficacy and biological properties.
Our Lead Optimization Capabilities:
Potency & Functional Characterisation
- We establish detailed potency profiles using relevant biochemical, binding, and cell-based functional assays. Candidates can be evaluated across concentration-response relationships to determine activity, efficacy, and functional consistency in appropriate biological models.
Selectivity Profiling
- Lead candidates are assessed for selectivity against related targets, receptors, pathways, or relevant cell populations. This helps identify potential off-target activity early and supports the selection of candidates with a stronger biological profile.
Mechanism-of-Action Studies
- We investigate how optimized leads produce their biological effects by examining target engagement, downstream signalling, pathway modulation, and relevant cellular responses. These studies help confirm that observed activity is consistent with the intended mechanism.
Structure–Activity Relationship (SAR) Support
- Biological data from iterative lead series are used to support SAR interpretation and guide subsequent compound or molecule design. By correlating structural changes with potency, selectivity, and functional activity, we help teams identify modifications that improve the overall lead profile.
ADCC & CDC Profiling
- For antibody-based programmes, we provide early assessment of antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) to understand Fc-mediated effector function and its contribution to the overall biological activity of the candidate.
Comparative Lead Profiling
- Multiple lead candidates can be evaluated head-to-head using a defined panel of functional and mechanistic assays. This enables objective ranking of candidates and helps identify molecules or biologics with the most favourable overall biological profile.
Modality-Specific Lead Optimization:
Monoclonal Antibodies (mAbs)
- We support characterization of antibody leads from binding and target engagement through functional activity, mechanism of action, Fc receptor interactions, ADCC, CDC, and early safety-relevant profiling.
Antibody–Drug Conjugates (ADCs)
- Our ADC biology capabilities include target engagement, internalization, payload activity, cytotoxicity, and bystander killing studies, providing a comprehensive understanding of how ADC design influences functional performance.
Cell & Gene Therapies
- We evaluate functional potency, cytotoxicity, cytokine responses, and immune-cell activation or exhaustion using physiologically relevant cell and co-culture systems. These studies help establish the functional characteristics of cell and gene therapy candidates.
Small Molecules
- Small-molecule leads can be assessed through target-based and phenotypic assays, potency and selectivity profiling, pathway analysis, and mechanism-of-action studies using relevant immune-cell models.
Integrated Data for Candidate Progression
Our lead optimization workflow is designed to generate decision-enabling biological data, rather than isolated assay results. By integrating potency, selectivity, mechanism, and modality-specific functional characteristics, we help identify leads that demonstrate the strongest combination of activity, specificity, and biological confidence.
The resulting data package can be used to support lead ranking, SAR decisions, candidate refinement, and progression toward Candidate Selection and IND-enabling studies.
