Non-affinity platform for processing knob-into-hole bispecific antibody

Area of Science:

• Biochemistry
• Biotechnology
• Protein Purification

Background:

• Bispecific antibodies offer therapeutic advantages but face development challenges due to byproduct formation.
• High and low molecular weight variants, along with homodimers, complicate downstream purification.
• Similar physicochemical properties of byproducts to target proteins hinder efficient separation.

Purpose of the Study:

• To develop a non-protein A purification platform for bispecific antibodies.
• To streamline purification processes and overcome challenges associated with byproduct removal.
• To provide a competitive alternative to traditional affinity chromatography methods.

Main Methods:

• A two-step chromatography approach was employed, utilizing mixed-mode Capto adhere resin for capture.
• The capture step was performed at pH 7.90 ± 0.10.
• Anion exchange chromatography served as the polishing step to achieve high purity.

Main Results:

• The purification method yielded a final product purity of 98% by size-exclusion high-performance liquid chromatography (SEC-HPLC).
• Reversed-phase-high-performance liquid chromatography (RP-HPLC) also confirmed 98% purity.
• Residual host cell proteins were controlled at 10 ppm with an approximate 60% recovery rate.

Conclusions:

• The developed non-protein A platform simplifies bispecific antibody purification.
• This method offers a streamlined and cost-effective alternative to conventional protein A affinity chromatography.
• The platform demonstrates significant potential for the commercial development of bispecific antibody therapeutics.