BioWorld International Correspondent

LONDON Avidex Ltd. said it succeeded in creating functional, stable and soluble T-cell receptors, unlocking the clinical and commercial potential of this immune system element in the same way the ability to engineer antibodies provided a therapeutic route to antigen targets.

James Noble, Avidex CEO, told BioWorld International, “We can make any [T-cell receptor] for use in vivo. We have dealt with all the practical issues of stability and solubility and the yield is very high.”

T cells, like antibodies, perform a vital role in the immune system, finding and destroying diseased cells or recognizing other foreign substances in the body. But whereas antibodies can lock only onto whole proteins on the surface of cells, the receptors on T cells can bind to peptide antigens within cells.

Peptide antigens have long been recognized as targets for therapy. “Lots of people have got peptide targets that they can’t use antibodies against,” Noble said. “We have developed our technology to the point that we can make any [T-cell receptor] specific for any disease peptide.” The T-cell receptors (TCRs) also are capable of carrying cytotoxic agents or radioisotopes.

Avidex’s monoclonal TCRs are based on fully human molecules, Noble said, meaning “there should, therefore, be no immune response.”

There has been interest from companies that want to use the technology to produce TCRs for particular targets, and Abingdon-based Avidex said it plans to enter partnerships.

The company also is developing an in-house program for cancer. Noble said that while the program is still early, a lot of cancer targets are known. “The point is, until now, no one was able to access them,” he said.

Avidex is using an earlier generation of TCRs to screen for small-molecule inhibitors in autoimmune disease, graft rejection and cancer. To date it has run three screens, and Noble said the screens “all worked perfectly, and we know we have hits from the first two.”

Avidex was formed in July 2000 around technology developed by Bent Jakobsen, who left his post at the Institute of Molecular Medicine at the University of Oxford to take up the position of chief scientist at Avidex. Avidex has raised £11.7 million (US$16.7 million) to date and Noble said he has offers of more than £10 million for the third funding round which he expects to close in June. Completing that round, he said is “a case of choosing the right balance of investors.”

Noble said the company has made “fantastic progress” since its formation, adding that “there were a lot of doubters, but we have kicked over a lot of serious hurdles.”