Development of Multi-Specific Antibody-Serum Albumin Fusion Proteins Targeting Multiple Human and Murine CXC (ELR+) Chemokines

Applications

This technology is an antibody-based therapeutic for rheumatoid arthritis.

Problem Addressed

Chronic inflammatory diseases, such as rheumatoid arthritis (RA), are very challenging to treat due to the numerous inflammatory ligands and receptors that participate in the inflammatory cascades that lead to disease. For example, in RA, the CXC chemokine system has multiple ligands and receptors that collectively contribute to an inflammatory response. There has been significant research attempting to block CXC-family receptors (CXCRs) or ligands (CXCLs) using antibodies, small molecules, or peptide inhibitors, however, these have not proven successful due to the CXC-family’s tremendous ligand and receptor redundancy. These inventors developed a new method to target multiple CXC ligands simultaneously, which greatly boosts the in vitro and in vivo inhibition of the CXC inflammatory response.

Technology

This technology uses an antibody that promiscuously binds multiple CXC chemokines to block the CXC inflammatory cascades associated with RA. A panel of promiscuous antibodies was developed through three sequential rounds of PCR-mutagenesis and directed evolution by selecting for antibodies with both promiscuous binding tendencies (binding to multiple CXCLs), and high binding affinity against multiple CXCLs. The antibodies were then fused to the serum albumin protein, which stabilizes the antibody in circulation and increases the in vivo half-life. The top three antibody hits from this directed evolution scheme blocked receptor activation in response to 2-5 different CXC ligands in vitro. Additionally, the inventors performed proof of concept experiments in an in vivo mouse model of RA that demonstrated a complete resolution of RA disease burden in only 10 days in response to the top candidate antibody.

Advantages

  • Promiscuous antibodies allow targeting of multiple CXC ligands with a single antibody formulation
  • Highly specific to CXC family ligands
  • Effectively reversed disease in a mouse in vivo rheumatoid arthritis model
  • Potential to translate to other diseases with CXC chemokine dysregulation such as irritable bowel disease and cancer