By Mary Welch

Only 10 months after signing a $30 million deal allowing Pfizer Inc. to use Abgenix Inc.'s XenoMouse technology to develop up to three fully human antibodies, the giant pharmaceutical company wants Abgenix to generate the second antibody. The antibody will be used for an undisclosed antigen target; the first antibody will be used for cancer research.

As part of the original deal, New York-based Pfizer made an up-front equity payment as well as agreeing to pay research costs, license fees and milestone payments. With Pfizer's selection of a second antibody, Abgenix, of Fremont, Calif., will receive up to $10 million in cash and is entitled to a "middle single-digit royalty payment based on sales," said Kurt Leutzinger, chief financial officer for Abgenix. Pfizer will also be responsible for manufacturing, product development and marketing of any resulting products. (See BioWorld Today, Jan. 5, 1998, p. 1.)

"We do not want to disclose any more of the financial arrangement, because we are in negotiations with other companies," he said. "Pfizer doesn't want us to be specific in what the area of research will be."

Abgenix's XenoMouse technology genetically rebuilds mice so that the genes that produce antibodies are shut down and replaced with human antibody-producing genes. The mice then produce fully human antibodies that, as immune system proteins, can combat many diseases.

"Antibodies are naturally occuring proteins that fight cancer and infections, but when companies tried to produce antibodies using mice, the human body would reject them. So companies tried to re-engineer or humanize the mice's antibodies to create a more human one," Leutzinger explained. "But about 10 percent of the mouse antibody remains. Since the antibodies produced by our mouse are human antibodies, we have no fear of rejection and they are very targeted."

According to Leutzinger, Abgenix is "catching a wave" with its new technology. "Pfizer was pleased with the first antibody we produced, so they came back for a second time — as did Genentech and Millennium. The message is getting out that the XenoMouse works and we expect our business model will start generating a stream of revenues."

In April, Abgenix signed an agreement with South San Francisco-based Genentech Inc. to use the XenoMouse technology for an undisclosed antigen target in the area of growth factor modulation. In June, Genentech signed a similar agreement for a second antigen target in the area of cardiovascular research.

In July, Abgenix and Cambridge, Mass.-based Millennium Pharmaceuticals Inc. signed an agreement to develop an antibody drug candidate toward a proprietary, biologically-validated targeted discovered by Millennium. Millennium came back a second time, in mid-October, to develop another antibody drug candidate.

Abgenix's stock (NASDAQ:ABGX) closed Monday at $8.625, up $1.125. *