Home page

Rapid Drug-likeness Analysis

Xichang Bio boasts extensive expertise in drug‑likeness assessment, protein engineering, candidate molecule design and expression, and in vitro efficacy evaluation for a wide range of novel molecular entities, including monoclonal antibodies, bispecific antibodies, and ADCs. This capability enables seamless integration between early‑stage drug discovery and CMC development, facilitating the advancement of superior candidates into the next phase of development.

Core Technological Advantages

Comprehensive Assessment System

Physicochemical characterization: Antibody aggregation propensity, charge heterogeneity, and thermal stability (with a Tm value > 70°C being preferred) are assessed using techniques such as SEC-HPLC, CE-SDS, and DLS.

Immunogenicity Prediction: By integrating AI algorithms with in vitro T-cell activation assays, we predict and mitigate the risk of anti-drug antibodies (ADAs) for humanized antibodies.

Functional activity validation: SPR/BLI assays for affinity determination (KD in the pM range), cell‑killing and blocking assays, and in vivo efficacy studies using PDX models and humanized mice—comprehensive multi‑dimensional evaluation of therapeutic efficacy.

Developability Assessment: Optimization of expression vectors and host cells (CHO/HEK293) to achieve high‑titer (>5 g/L) and stable large‑scale production.

Rational Design Optimization

Enhanced stability: By introducing site-directed mutations or engineering glycosylation, the antibody’s resistance to proteolytic degradation and its serum half-life are improved.

Reducing aggregation risk: substituting hydrophobic residues and optimizing the charge distribution in the CDR regions to ensure that the monomeric form accounts for >95% of the formulation.

Humanized fine-tuning: Employing a CDR grafting plus framework region optimization strategy, this approach preserves biological activity while reducing the incidence of HAMA (human anti‑mouse antibody) responses to below 5%.

Service Content

Serial number	Molecular characteristics	Assessment methods
1	Sequence and Structural Assessment	In Silico Method
2	Molecular size and purity	SEC-HPLC method
3	Molecular size and purity	Recovery of the CE-SDS method
4	Molecular size and purity	Non-reducing CE-SDS method
5	Isoelectric point	iCIEF method
6	Charge purity	iCIEF method
7	Charge purity	CEX-HPLC method
8	Mass spectrometry molecular weight	RP-MS method
9	Post-translational modification	RP-MS/MS method
10	Solubility	PEG method
11	Thermal stability (Tm/Tagg)	UNCle Law
12	Colloidal stability (kD)	UNCle Law
13	Particle size	UNCle Law
14	Self-interaction	AC-SINS method
15	Nonspecific binding	BVP method
16	Nonspecific binding	Off-target cell assay
17	Binds to proteins of the same family	BLI method/ELISA method
18	Binding of proteins from different species	BLI method/ELISA method
19	PK-related features	Heparin column method
20	Antigen affinity	BLI method
21	Biological activity	Cell method
22	Fc Function Assessment	BLI method (optional for different receptors)
23	ADCC/CDC/ADCP	Cell method
24	Plasma/Serum Stability	Cell method
25	Endocytosis	Cell method
26	Bystander effect of harm	Cell method
27	Cell cycle arrest	FACS method
28	Forced degradation stability	High temperature, light exposure, strong oxidizing agents, high pH, low pH, freeze–thaw cycles, and shaking—select as needed.

Serial number	Quality Research	Analytical method
1	Variable-temperature mass spectrometry molecular weight analysis	RP-MS method
2	Non-variant mass spectrometry molecular weight analysis	SEC-MS method
3	Complete Amino Acid Sequence Analysis	RP-MS/MS method
4	Post-translational modification analysis	RP-MS/MS method
5	Extinction Coefficient Analysis	RP-HPLC-FLD method
6	Identification of N-glycosylation sites	RP-MS/MS method
7	Analysis of N-glycosylation composition	HILIC-FLD method
8	Sialic Acid Content Analysis	RP-HPLC-FLD method
9	Free thiol analysis	Ellman Assay method
10	Disulfide Bond Analysis	RP-MS/MS method
11	Secondary/Tertiary Structure Analysis	Circular dichroism spectroscopy
12	Tertiary structure	Protein autofluorescence scanning method
13	Dual-antibody mismatch analysis	(iCIEF or HIC) /CE, etc.
14	Sequence Variant Analysis	RP-MS/MS method
15	Collection and Identification of Acid–Base Peaks	CEX-HPLC/RP-MS, etc.
16	Collection and Identification of Polymer Fragments	SEC-HPLC/RP-MS, etc.
17	Collection and Identification of DAR Heteromers	HIC-HPLC, RP-MS, etc.
18	Qualitative Analysis of High-Risk HCPs	RP-MS/MS method
19	Quantitative Analysis of High-Risk HCPs	RP-MS/MS method
20	HCP Coverage Analysis	2D-WB method
21	HCP Coverage Analysis	RP-MS/MS method
22	Analysis of Tuan degradation products	RP-HPLC-CAD method
23	Average DAR Value Analysis	HIC or RP method
24	DAR Value Distribution Analysis	HIC or RP method
25	Coupling Site Analysis	RP-MS/MS method
26	Polymeric form identification	SEC-MALS method