Avidex Generates High Affinity Monoclonal T Cell Receptors
OXFORD, England, June 23 /PRNewswire/ -- Avidex Limited, an Oxford-based company specialising in the development of therapeutics based on its proprietary T Cell Receptor technology, announces that it has made a key breakthrough with its monoclonal T cell receptor (mTCR) technology and that the company is now able to engineer T cell receptors with high affinity and specificity.
Preliminary results are being presented at the BIO 2003 Annual Conference in Washington. Full results are expected to be published in a peer-reviewed journal.
Commenting on the breakthrough, James Noble, CEO of Avidex, said: "Over the last 20 years, great efforts have been invested in the production of antigen specific antibodies as therapeutics and particularly as targeting agents for cancer. Through high affinity mTCRs, it is now possible to target cancer antigens which are well characterised but are not targeted by antibodies. Monoclonal T Cell Receptors exploit the natural targeting mechanism for T cells which are activated to kill diseased cells in the body. We have now overcome the technical hurdles to generating mTCRs that have the characteristics of monoclonal antibodies and thus with genuine therapeutic potential."
Further information
James Noble, CEO of Avidex, will be presenting the new data at the BIO meeting in Washington, D.C. on 25th June 2003 and Dr. Neill Moray MacKenzie, CBO of Avidex will be available throughout the conference at the Avidex exhibition stand, in the UK pavilion, booth #665.
Background and Details
Antibodies and T Cell Receptors
Antigen-specific antibodies have been the focus of huge investment as therapeutics and as targeting agents in cancer. Until recently, no company had looked at the antigen receptors on T cells as an alternative in view of the difficulty in making these T Cell Receptors ("TCRs"). TCRs are, however, a key component of the human immune system, because they are the natural targeting mechanism for T cells, which are activated to kill diseased cells in the body. Many cancer antigens are already well characterised and are suitable targets for TCRs, but cannot be targeted with antibodies.
Today's breakthrough
From the outset of its research Avidex realised that mTCRs require two key properties, to be of high affinity and specificity. These properties are essential to ensure that the mTCRs are directed specifically to the diseased cells and that they remain bound to those cells.
In today's breakthrough, Avidex has now developed and patented a method of increasing the affinity of its mTCRs while retaining the natural specificity of the molecules. Avidex is now able to create mTCRs which:
-- Are fully human
-- Have low nanomolar affinity and so bind tightly to the target
-- Are specific for a given antigen-presenting cell
-- Have a slow "off rate" and so remain bound to the target
The effect of this breakthrough is that the mTCRs now have the characteristics which have been proved to be necessary for successful antibody development.
The Avidex pipeline
Using the mTCR technology Avidex has created a pipeline of therapeutic products for the treatment of cancer and autoimmune disease.
-- Cancer - by targeting therapeutic moieties to cancer-specific antigens
and killing tumour cells
-- Autoimmune diseases - by blocking of the interaction between antigen
presenting cells and T cells and inhibiting aberrant T cell activation
The mTCR technology is capable of being applied to any HLA/peptide antigen combination.
Notes to Editors
About Avidex Limited
Avidex is a biotechnology company focussed on the development of therapeutics for cancer and autoimmune diseases. Through its knowledge and understanding of T cell receptors (TCRs), the Company has developed novel therapeutic approaches where TCRs act as the target or targeting molecule. In addition to protein therapeutics, Avidex is also progressing with lead optimisation of the CD80 antagonist, RhuDex(TM) for rheumatoid arthritis. Avidex is developing this pipeline of protein and small molecule drugs and its strategy is to take products through final developmental phases and to the market through corporate alliances. Avidex also commercialises its proprietary mTCR platform through partnerships.
The Company's lead programmes include MiDex(TM), a protein therapeutic for autoimmune disease, RhuDex(TM) a small molecule immune suppressant, and mTCRs, fully human, soluble T cell receptors.
Avidex was formed in 1999 as a spin out from Oxford University. The Company employs 52 staff and is based in Milton Park, near Oxford, UK. The Company has raised 23.2 million pounds sterling to date, with investors including Advent Venture Partners, The University of Oxford, Oxford Technology Venture Capital Trust plc and Quester.
The Avidex TCR technology
Avidex has a unique, patented method of making soluble TCRs (i.e., TCRs no longer attached to the T cell) and is investing its resources in improving the qualities of its TCRs so as to make targeting agents for cancer and autoimmune disease.
Prior to today's announcement, Avidex had cleared many technical hurdles with its mTCRs, including:
-- Fully human proteins - unlike many antibodies
-- Full structural integrity - the mTCRs incorporate both chains of the
natural TCR
-- Stability - the TCRs are stable for at least a year
-- Ease of manufacture - the mTCRs are made in E. coli, a simple and
relatively inexpensive process
Today's announcement addresses the key remaining characteristics of an mTCR that makes it a suitable therapeutic candidate.... |
