LONDON - The first fully human monoclonal antibody has entered Phase III clinical trials in rheumatoid arthritis. D2E7, an anti-tumor necrosis factor antibody, was discovered by Cambridge Antibody Technology Group plc and is partnered by BASF Pharma, which has sole responsibility for development and marketing.

John Aston, finance director of CAT, based in Cambridge, England, told BioWorld International, "The first fully human monoclonal to go into Phase III is significant in itself, especially as we have others following, but the rheumatoid arthritis market D2E7 is attacking is also significant."

The transition triggered an undisclosed milestone payment to CAT. "It wasn't a multi-million pound payment," he said, "but of the same order as our other milestones. To date our revenues have been around #2 [million] or #3 million per annum, so that gives an idea."

Three other human monoclonal antibodies developed with CAT's technology are also in clinical trials. They include CAT 192, an anti-transforming growth factor beta 1 monoclonal antibody that has just completed Phase I. CAT is carrying out development itself, and Aston said patient trials will start later this year. The compound has the potential to provide the first specific treatment for a range of local and systemic fibrotic conditions, and the indication is yet to be decided.

CAT's share price rose by 65 pence to #13.65 when the move into Phase III was disclosed Friday. This was the latest in a series of stock price increases following the signing of the company's biggest deal to date, a US$212 million alliance with G.D. Searle & Co. Since the alliance was announced on Dec. 24, CAT's stock price has jumped from #2.

Aston said, "The Searle deal attracted a lot of interest from U.S. investors, who have been comparing our stage of development to our U.S. peers, Medarex and Abgenix. In terms of products in the clinic we are more advanced. They [Medarex Inc. and Abgenix Inc.] do more deals, but these are probably lower in value, at least in the first instance, because they are options on product development whereas ours are for money up front." The market capitalization of Abgenix is around $3 billion, while that of CAT is around $600 million.

Aston also noted that although the share price has risen significantly in the past six weeks. CAT floated at #5 per share when it went public in March 1997, and started trading at #6 per share. "So, taken overall, we are looking at an increase of 30 percent per year," he said.