Imunexus’ Multispecific Technology

Our unique patented approach can be used to potentially convert almost any antibody or other protein into a bispecific or trispecific. A major advantage of the Imunexus approach is that the technology has been developed as a method for “converting or retrofitting” antibodies or other proteins into multispecifics.  Our technology can add up to two additional specificities to antibodies while retaining the original antibody without perturbing its therapeutic properties or manufacturability. Our approach is subject to patent and patent applications extending to 2036.

What are ImunexinsTM

ImunexinsTM have been engineered from a naturally occurring human non-antibody protein sequence with physical properties similar to those of the binding regions of antibodies VH domains). The physical properties of ImunexinsTM allow easy manufacturing, can be engineered to bind to any target of interest and allow genetic fusion to other protein sequences without perturbation of either the parent sequence or the ImunexinTM.

Efficient and Simple Multispecific Antibody Generation via the ImunexinTM Platform

ImunexinsTM engineered to bind to specific therapeutic targets are genetically fused to an existing antibody via simple (standard protocols), quick (weeks) and cheap ($1000’s) methodology. ImunexinsTM can be fused to the constant heavy and/or to the constant light regions of an antibody. The resulting bi- or trispecific antibody can now bind to two or three distinct targets simultaneously.

Diagram showing a monospecific antibody converted into a bispecific or trispecific by genetically fusing ImunexinsTM to the antibody

Multi Specificity Antibodies Allow for More Potent Antibody Drugs

Multi targeting antibodies can be designed to:

  • Redirect and activate immune effector cells to specifically kill tumours.
  • Bind to multiple targets and effect multiple pathogenic pathways.
  • Bind to multiple sites on the one target cell or protein to increase specificity or induce synergistic induction.
  • Target tumours that are heterogeneous.
  • Increase the half-life of whole antibodies or antibody fragment.
  • Bind to transport proteins to allow antibodies to cross biological barriers.

Two potential applications of Imunexus’ bispecific technology are currently being developed. We are developing:

  • Immune enhancing bispecifics, to increase potency; and
  • Bispecifics with extended serum half-life.

The Advantages  of ImunexinTM  Multispecific Antibody Approach

Simple and highly efficient multispecific antibody generation:

  • Applicable to any antibody sequence.
  • No antibody- ImunexinTM matching needed.
  • Antibody retains original binding sites and specificity.
  • ImunexinsTM are simply cloned into exiting IgG vectors with no additional protein engineering required.

The parent antibody retains its original structure and function:

  • Antibody functions are fully retained.
  • Antibody retains its original binding avidity.
  • Antibody-mediated effector functions are retained or can be modulated for select applications.
  • Antibody pharmacokinetics including serum half-life are retained.


  • ImunexinsTM are human in origin and are potentially less immunogenic.
  • ImunexinsTM fused to antibodies show binding avidity.
  • No reformatting is required post discovery stage.
  • Discovery is via high throughput screening of our 10+10 randomised libraries via the Company’s proprietary HTP screening technology.

Integrates seamlessly into existing production processes:

  • Manufacturing, purification, formulation and all other processes based on standard IgG processes remain the same.

Rapid development of bispecific antibodies from concept to investigational drug

Our strategy of re-engineering marketed and clinically validated antibodies carries key advantages over many other drug development approaches in that:

  • Each ImunexinTM can be “bolted on” to multiple marketed or partnered investigational antibodies to rapidly (within months) generate improved antibody therapeutics.
  • The development risks are lower as the properties of an enhanced, pre-existing marketed drug are more predictable.
  • Imunexus’ proprietary rapid-screen technology can identify new ImunexinsTM and re-engineer existing antibodies at a fraction of the cost of traditional antibody discovery.

We believe that we can re-engineer an existing marketed or clinically validated antibody (partnered or in-house) with significantly improved immune activation properties for a fraction of the time and cost of traditional antibody drug development techniques.