By Brady Huggett

Staff Writer

Protein Design Labs Inc. disclosed three bits of news, all of which could add to what the company said it already has: a deep pipeline and solid foundation.

Of the developments, perhaps most notable was Exelixis Inc., of South San Francisco, delivering several cancer antibody targets to PDL through their collaboration, initiated in May. With targets in hand, the next step will be to evaluate them, said Robert Kirkman, vice president, business development and corporate communications at PDL. (See BioWorld Today, May 24, 2001.)

“Both we and they will be conducting a series of assays to validate these targets,” he said. “We’ll be dividing that work; some of it will be done here and some will be done there.”

PDL, of Fremont, Calif., purchased a $30 million convertible note in the deal, convertible after one year into shares of Exelixis stock, and also will fund Exelixis’ research in the collaboration, paying about $4 million per year for at least two years. Exelixis has the right to co-fund and co-develop antibodies, but if it chooses not to participate to that extent, Exelixis would receive milestones and royalties.

That fork in the road for Exelixis is still at some distance, Kirkman said.

“[Exelixis doesn’t] make the decision until we actually file an [investigational new drug application], so we are a ways from making that decision,” Kirkman said. The companies are not disclosing the targets they might be appropriate for, he said, but the research is designed to drive one or two new development candidates into the clinic each year.

On Tuesday PDL said it entered a two-year patent rights agreement with American Home Products Corp., of Madison, N.J., making it the third “significant arrangement” it has with AHP and its subsidiaries, Kirkman said. AHP has a nonexclusive license under PDL’s antibody humanization patents to market Mylotarg, a drug approved in May 2000 for the treatment of patients 60 years or older in first relapse with CD33-positive acute myeloid leukemia who are not considered candidates for cytotoxic chemotherapy. PDL is currently receiving royalties on that product, Kirkman said.

PDL also has humanized three antibodies for Wyeth-Ayerst Research, a division of AHP, Kirkman said, two of which are in Phase II trials in solid-organ transplantation.

Under the current agreement, PDL receives a nonrefundable, noncreditable up-front license fee and AHP obtains a worldwide, nonexclusive license for antibodies to a specific, although undisclosed, target antigen.

“It’s similar to previous deals we’ve done in the past, such as with Genentech [Inc., of South San Francisco] in 1998, where we got an up-front fee of about $1 million per antigen,” Kirkman said. Since this deal is for a specific antigen and slated for two years instead of the five-year deal with Genentech, Kirkman said this deal is worth somewhat less than that.

On Wednesday, Rosetta Inpharmatics Inc., of Kirkland, Wash., said PDL licensed the Rosetta Resolver Gene Expression Data Analysis System. PDL will use the license to help it evaluate specifics of the Exelixis arrangement, Kirkman said, as well as evaluate other programs such as its work in autoimmune disease.

Also this week PDL suffered some fallout Tuesday from the FDA’s call for more data on Genentech’s Xolair biologics license application, a product in PDL’s arena of monoclonal antibodies. Genentech’s stock fell nearly 16 percent, while partner Tanox Inc.’s shares dropped 44 percent. PDL’s shares fell $9.96 Tuesday to close at $63.13.

But Kirkman said PDL likes where it is with seven antibodies in clinical trials; its product, Zamyl, in a Phase III trial in patients with acute myeloid leukemia with data expected to be presented at the American Society of Hematology, held in Orlando in December; and more than $660 million in cash and cash equivalents.

“We think this pipeline is incredibly strong and this is the major focus at PDL at this time,” he said. “The reaction [Tuesday] in the delay of Xolair was, at least in our case, a significant overreaction. The strength of our company is certainly in our pipeline.”

PDL’ s stock (NASDAQ:PDLI) fell 42 cents Wednesday to close at $62.77.