RUBY® - a tetravalent (2+2) bispecific antibody format with excellent functionality and IgG-like stability,...

Area of Science:

• Biotechnology
• Immunology
• Protein Engineering

Background:

• Existing bispecific antibody (bsAb) formats face development and bioprocessing challenges.
• Novel bsAb formats are needed to overcome these limitations and improve therapeutic potential.

Purpose of the Study:

• Introduce the novel RUBY bispecific antibody format.
• Evaluate the developability, functionality, and pharmacokinetic properties of RUBY bsAbs.
• Demonstrate the advantages of the RUBY format over existing bsAb strategies.

Main Methods:

• Designed a novel 2+2 geometry bispecific antibody format (RUBY) with optimized chain pairing.
• Assessed small-scale and large-scale production compatibility, yield, and purity.
• Evaluated bsAb aggregation, solubility, stability, Fc receptor binding, and FcRn interaction.
• Determined in vivo pharmacokinetics in mice and non-human primates.
• Confirmed in vitro functionality and in vivo tumor penetration and localization.

Main Results:

• RUBY enables rapid generation of bsAbs with monoclonal antibody (mAb)-like attributes.
• High yields (>3 g/L) and low aggregate levels were achieved from stable cell lines.
• RUBY bsAbs exhibited favorable solubility, stability, and tailored Fc receptor binding.
• Pharmacokinetics in mice and non-human primates were comparable to mAb controls.
• In vivo tumor penetration and localization were demonstrated, with previously shown superior anti-tumor effects.

Conclusions:

• The RUBY format offers a viable solution to mitigate development challenges associated with bispecific antibodies.
• RUBY bsAbs possess attractive mAb-like attributes, facilitating high functionality and improved developability.
• This novel format holds significant promise for advancing bispecific antibody therapeutics.