BioWorld International Correspondent

LONDON — Antisoma plc has renegotiated its licensing deal with Abbott Laboratories Inc. for pemtumomab, under development for the treatment of ovarian and gastric cancer, a move that will mean Antisoma takes on an extra £9 million (US$12.9 million) in development costs over the next three years in return for higher milestone and royalty rates.

Glyn Edwards, CEO of Antisoma, told BioWorld International that the alterations were spurred by changing circumstances at both companies but did not mean Abbott is any less committed to pemtumomab. “There are issues on both sides that led to the renegotiation, but the overall structure of the deal is not changed that much. It is a fine-tuning of an existing deal, not a radical restructuring.”

Antisoma, based in London, needs to raise more money before the middle of 2002 but had balked at doing so under current market conditions. Edwards said he had approached Abbott to see if the company was prepared to put in more money up front in return for a lower royalty rate, to get some cash into Antisoma. Abbott agreed in principle but Edwards said the royalty rate offer was too low.

“Since we needed to raise more money anyway, in the end we decided we would bear more of the costs in return for a higher royalty rate than the original deal.” The two were splitting development costs, with Abbott paying 70 percent. From now on Antisoma will take on all development costs of pemtumomab, which is in Phase III.

Under the original deal with Abbott, entered in November 1999, Antisoma was to receive US$85 million in development, registration and sales milestones; that total has increased to $91 million.

To date Antisoma has received £26 million from Abbott for pemtumomab. The product, a yttrium-90 radiolabeled antibody, was expected to receive approval in 2002. However, in June 2001 the FDA told Antisoma to increase the number of patients in the Phase III trial in ovarian cancer, delaying the program by 18 to 24 months, and leaving Antisoma with a funding gap.

Edwards said the increased expenditure on pemtumomab means Antisoma will have to reach the top end of the £15 million to £20 million it has told analysts it plans to raise from the market in the next two years. The company also expects to raise a similar amount from partnering deals, and Edwards said discussions are well under way with potential licensees.