By Matthew Willett

When old friends get together it isn't surprising to see a new development or two.

Princeton, N.J.-based Medarex Inc., Biosite Diagnostics Inc. and Eos Biotechnology Inc., all already collaborators, joined in a new collaboration that aims at using Eos targets to create anticancer antibodies using Medarex and Biosite's Transphage Technology.

The triple collaboration calls for South San Francisco-based Eos to provide Biosite, of San Diego, with tens of targets over three years, development fees, milestone fees, royalties from successful products and annual target maintenance fees.

"Most deals are two-party collisions," Eos CEO David Martin joked. "This is a three-party collision, if you will. What's different is that we, and we think Medarex and Biosite as well, clearly recognized that none of us has all the technology and the expertise we need to be successful, but we're willing and desire to partner appropriately and share in the benefits. We assume that by partnering we can create, as Don [Drakeman, Medarex CEO] says, 'more shots on goal,' and share the proceeds."

In this collaboration, Biosite will get diagnostic rights to the targets, and Medarex expects to receive payment pursuant to its existing collaboration with Eos, entered in 1999, that called for antibody generation for Eos anticancer targets.

That anticancer antibody generation deal's expansion last February gave Eos access to Medarex's HuMAb-Mouse technology for antibody production as well as up to $75 million in cash, credit and potential milestone payments. Medarex and Eos will jointly own any resultant products from the six- to nine-candidate deal. (See BioWorld Today, Feb. 15, 2000.)

Medarex CEO Donald Drakeman said the combination of Biosite's Omniclonal phage display technology and his company's HuMAb-Mouse antibody generation technology should be useful to Eos.

Medarex and Biosite joined technologies in June in a $24 million deal that the companies aimed at using to lure partners. The companies said at the time that they would seek partnerships like this one, the first since their alliance was formed. (See BioWorld Today, June 2, 2000.)

"Traditional phage display is that the phage tries to create antibody fragments from naove libraries, randomly created libraries, and that's a little hit or miss," Drakeman told BioWorld Today. "We handle here, instead of naove libraries, what we call immunized libraries. We take the target and immunize one of our transgenic mice, which creates an immune response. Then we take the cells that create the antibodies and apply the phage to create huge libraries of antibody fragments to specific targets of interest. It's a precise tool to create many antibody fragments to precise targets."

The deal represents the 32nd collaboration using Medarex's HuMAb mouse, Drakeman said.

Biosite's vice president of corporate and investor relations, Nadine Padilla, said the diagnostics rights are the richest downstream part of Biosite's deal with Eos and Medarex.

"For diagnostics we have a very aggressive effort under way to discover new markers for diseases that lack blood tests," Padilla said. "We're trying to gain as much access as possible to targets that we can put into our marker mining process that will tell us if we do have a diagnostic application there. If we find something good enough we'll put it in the product development pipeline, and that will benefit our partner as well since the diagnostic product development cycle is much less than drug discovery, and they'll receive some royalty should we develop some diagnostic product from a target."

Medarex's stock (NASDAQ:MEDX) rose $4.125 Monday, or 20 percent, closing at $26.688. Biosite's shares (NASDAQ:BSTE) rose $1.875 to close at $37. Eos is privately held. n