PEG & ADC

Monoclonal Antibody-drug Stability Optimization

Monoclonal Antibody-Drug Stability Optimization

Monoclonal antibody drugs are essential in biopharmaceuticals, known for their precise targeting and high specificity. With the continued advancement of antibody technology, these drugs are increasingly critical in disease prevention, diagnosis, and treatment.

However, as proteins, monoclonal antibodies are vulnerable to environmental changes during production, storage, and in the body. These changes can significantly affect stability, increase immune response, and even cause drug failure. Therefore, stability improvements are vital to enhance bioavailability, reduce immunogenicity, and extend the drug’s half-life. Below is an outline of key approaches and methods for stability optimization.

1. Structure and Stability of Antibodies

Strip chart and molecular structure of IgG antibody

Antibodies are specialized proteins that bind specifically to antigens. Monoclonal antibodies (mAbs) originate from a single cell line, allowing precise targeting. Structurally, they consist of two heavy and two light chains forming a “Y” shape. The arms (Fab) bind antigens, while the tail (Fc) supports the immune response. This structural stability is essential for the antibody’s function in therapy.

Some antibodies show excellent performance in laboratory tests but lose effectiveness when used in the body. Thus, early stability testing is important. Stability can be improved through structural adjustments, chemical modifications, or adding stabilizers. For instance, a mineralized calcium shell can protect the protein, increasing its resilience.

2. Methods to Test Stability

When it comes to assessing antibody stability, testing typically includes biological activity, structure, purity, and environmental factors like pH. Together, these tests evaluate thermal stability, aggregation, and intermolecular forces.

Differential Scanning Calorimetry (DSC) is a commonly used tool for thermal stability, measuring melting temperature and energy changes. Additional methods, like CIC, AC-SINS, and CSI-BLI, assess solubility and predict interactions. Furthermore, computer-aided design (CAD) software supports structural modeling to identify areas for stability improvements.

3. Strategies for Stability Improvement

3.1 Structural Changes

Modifying antibody structures is an effective way to boost stability. For example, substituting the amino acid Asn with Gln in specific antibody regions can help reduce degradation.

3.2 Process Optimization

Antibodies are often sensitive to extreme pH, which can cause degradation. Adding stabilizers like maltose in formulations helps counteract this. Surfactants, such as polysorbates, also help by reducing aggregation. Arginine can further increase solubility, protecting the antibody from light and heat damage.

Additionally, improving storage and packaging methods significantly enhances stability. For example, using coatings on containers prevents antibodies from sticking to surfaces, preserving function and stability.

4. Conclusion

Monoclonal antibodies are indispensable in modern biomedicine, with expanding applications in single-chain, single-domain, and antibody-drug conjugates (ADCs). Because stability optimization is crucial, it helps ensure targeted drug action, reduces immune response, and maintains effective dosage.

Effective antibody stability testing includes physical, chemical, and biological assessments. Understanding these factors, along with employing reliable testing methods, enables better antibody development and supports the delivery of stable, effective antibody therapies to patients.

AxisPharm provides various ADC cross linkers and offers comprehensive antibody and antibody drug conjugate mass spec analysis services.

Ref:

[3] Salmaso V, Moro S.Bridging Molecular Docking to Molecular Dynamics in Exploring Ligand-Protein RecognitionProcess: An Overview[J].Front Pharmacol,2018,9:923.doi:10.3389/fphar.2018.00923

[6]Hogiri T, Tamashima H,Nishizawa A , et al .Optimization of apH-shift control strategy for producing monoclonal antibodies in Chinese hamster ovary cell cultures using a pH-dependent dynamic model[J].J BiosciBioeng,2018,125(2):245-250.doi:10.1016/j.jbiosc.2017.08.015

[8]Toth RTt, Pace SE, Mills BJ , et al .Evaluation of Hydrogen Exchange Mass Spectrometry as a Stability-Indicating Method for Formulation Excipient Screening for an IgG4 Monoclonal Antibody[J].J PharmSci,2018,107(4):1009-1019.doi:10.1016/j.xphs.2017.12.009

[10]Sreedhara A, Glover ZK, Piros N , et al .Stability of IgG1 monoclonal antibodies in intravenous infusion bags under clinical in-use conditions[J].J PharmSci,2012,101(1):21-30.doi:10.1002/jps.22739

[12] Giamblanco N, Marletta G,Graillot A , et al .Serum Protein-Resistant Behavior of Multisite-Bound Poly(ethylene glycol) Chains on Iron Oxide Surfaces[J].ACSOmega,2017,2(4):1309-1320.doi:10.1021/acsomega.7b00007