The Avibody™ Technology
Antibodies or "immunoglobulins" are key proteins in the body's immune system and have the function of binding to and removing any foreign or disease-causing agents. Antibodies do this by recognizing these agents through "Target Binding Regions" (TBRs) leading to activation of the body's various defence systems. Avibody™ products are an improved format of antigen-binding molecule and contain either two, three or four TBRs more commonly known as Dia-, Tria- and Tetra-bodies. Engineered antibodies have expanded the frontier of the biotechnology and pharmaceutical industry by achieving over US$10 billion in annual sales in cancer and inflammatory disease.
What are Avibody™ products:
Intact Antibodies (also known as monoclonals) bind to their targets through their target binding regions (TBR) also known as Fv domains. Avipep's proprietary technique offers a method to express just the Fv domains and to link them together into stable, specific and highly customizable multimeric antibody-like proteins known as Avibody™ proteins. This is achieved by the patented method of fusing the V-domains in an Fv together in a "head to tail" orientation (in the Figure the V-domains are the oval shapes).
Avipep's platform technology to generate Avibody™ products addresses the many unmet needs in the molecular imaging and therapeutic antibody space. In doing so, Avipep takes advantage of a rapidly growing sector that is now well accepted by market and regulatory bodies.
Recombinant antibody fragments offer numerous advantages over classical antibodies, and are well positioned to become the paradigm for the next generation of reagents for in vitro and in vivo diagnostic and therapeutic applications. The key advantages of Avibody™ products are summarized below:Market Drivers of the Antibodies Avipep Affinity scaffolds with high diversity in antigen binding. High target selectivity and affinity/avidity. Low molecular weight and increased bioavailability and tissue penetration. Customizable effector functions (drug/imaging payloads). Customizable in vivo half-lives. High yield in bacterial expression systems. Low royalty stacking. Freedom to operate on high value targets. Preclinical validation in multiple antigen systems.
These non-covalently assembled multivalent recombinant antibody fragments, diabodies, triabodies and tetrabodies, offer an improvement over their whole antibody equivalents.
Most importantly the increased tissue penetration, high avidity (slow off-rates) and fast blood clearance has resulted in dramatic tumour localisation of Avibody™ reagents in our animal models, with pre-clinical trials underway and clinical trials schedule to begin in 2010.