McFusion Technology

A Novel Platform for Production of FcFusion Proteins in E. coli

Highlights:

• McFusion is a novel platform technology developed by MCLAB  for the production of soluble and active form of Fc fusion proteins in E. coli
• McFusion platform technology has been successfully applied to produce Fc-fusion proteins of human growth hormone (hGH), glucagon-like peptide 1 (GLP1), interleukin-2 (IL-2), and single chain antibodies
• The production process of McFusion technology is fast, robust, highly efficient and very costly competitive comparing to other current Fc fusion technologies

Introduction

Fc fusion is an established technology used to prolong the half-life of several drugs licensed for the long-term treatment of a number of chronic diseases. Current Fc-fusion therapeutic proteins are expressed in mammalian cells, and only the peptide-Fc fusion proteins (peptibodies) are expressed in an insoluble form in E. coli. MCLAB has developed a novel Fc fusion technology platform (McFusion) for producing long-acting therapeutic proteins in E. coli. Preclinical studies have demonstrated that McFusion technology platform can improve the pharmacokinetic (PK) and pharmacodynamic (PD) properties of proteins that can be dosed once a week or even less frequently.

 

• Fc region of IgG4 expressed in E. coli as aglycosylated Fc in order to remove the effector from IgG1 Fc, which reduces cytotoxicity from antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC), and increases safety of therapeutic Fc fusion protein
• Genetically modified and optimized hinge region to improve soluble expression in E. coli and aid in folding of Fc-fusion proteins
• Optimized the flexible linker to increase soluble expression, minimize the loss of bioactivity of the drug protein and reduce immunogenicity

Production of Soluble and Bioactive Fc-Fusion Proteins in E. coli

• Optimized construct with a combination of a IgG4 Fc region, a genetically modified hinge region and a flexible linker
•  Optimized expression system with suitable vector and E. coli strain
•  Optimized culture and expression conditions
•  Optimized extraction and purification process
•  Successful applications of McFusion technology to  Fc-fusion hGH (MC2-hGH), Fc-fusion GLP 1 (MC2-GLP1)  and Fc-fusion IL2 (MC2-IL2)
•  Current Productivity : ~ 2 g/liter with 50 % recovery; simple and fast manufacturing process with high purity and high bioactivity

Experimental data

1. Binding of Fc Domain of MC2-hGH to Fcγ Receptor I

 

 

 

 

 

2. McFusion Extended Half-life of hGH in Rats

 

• The result of pharmacokinetics (PK) study in rats is shown in Fig. 3
• MC2-hGH extended the half-life of hGH to 40 hours in rats, which is 100 times longer than that of rhGH
• Half-life of protein in human is expected to be 3 folds in rats
• In addition, hGH could be detected after more than 14 days with a single injection of MC2-hGH to rats

Efficacy of MC2-hGH Equivalent to rhGH

• The result of  pharmacodynamics (PD) study in rats is shown in Fig. 4
• In the two-week animal study，the total molars of hGH are the same between 0.15 mg/kg hGH daily and 2.4 mg/kg MC2-hGH weekly
• At day 14, weight gains in the group with injection of MC2-hGH are higher than the group with hGH
• With a double dose of MC2-hGH, weight gain also increased significantly
• McFusion extended the half-life of hGH and achieved long-acting therapeutic effect; MC2-hGH could be dosed weekly or even bi-weekly

Conclusions

• McFusion is a novel Fc-fusion technology platform to develop long-acting therapeutic proteins
• McFusion technology platform enables the production of soluble Fc fusion protein in E. coli, which confers the production process is fast, robust,  highly efficient, and very costly competitive comparing to other current Fc fusion technologies
• Preclinical studies have demonstrated that a Fc fusion protein, hGH, produced by McFusion technology has improved the PK and PD properties.