IDEC Pharmaceuticals Corp. said Wednesday it entered its fifthresearch and development collaboration, this one focused ondevelopment of both humanized and Primatized antibodies to thegp39 antigen.

IDEC, of San Diego, can receive up to $37.5 million in pre-commercial payments in the collaboration with Eisai Co. Ltd.targeting antibody-mediated autoimmune diseases such as lupus andidiopathic thrombocytopenic purpura.

The collaboration, made in December and announced Wednesday,included an up-front payment and initial license fee of $4.5 million,said David Ludvigson, IDEC's senior vice president and chieffinancial officer. He said about two-thirds of the potential $37.5million is in research and development support with the remainder inmilestones.

In return Eisai, of Tokyo, received exclusive rights to develop andmarket resulting products in Japan, Asia and Europe, with IDECgetting royalties. IDEC retained rights in North America andelsewhere.

IDEC's stock (NASDAQ:IDPH) gained $1.25 Wednesday to close at$20.38. The stock traded as low as $2.13 in 1995.

The gp39 antigen, also called the CD40 ligand, is an immune systemtrigger for B-cell activation and antibody production.

"Anti-gp39 antibodies inhibit B-cell function by interfering with thebinding of gp39 to CD40, thus blocking signals that trigger B-celldifferentiation and the production of IgG, IgA and IgE antibodies,"Nabil Hanna, IDEC's senior vice president of research andpreclinical development, said in a news release. "Studies by Dr.Randy Noelle, our collaborator at Dartmouth University, have shownanti-gp39 antibodies to be effective in animal models of SLE[systemic lupus erythematosus], rheumatoid arthritis, multiplesclerosis, diabetes and transplantation."

IDEC licensed the technology from Dartmouth, of Hanover, N.H.IDEC picked up the work in mouse antibodies at the university and ishumanizing them, thus reducing the development time, Ludvigsonsaid. Part of the work with Eisai will center around development of asecond-generation Primatized anti-gp39 antibody.

Primatized antibodies, which are part of four of IDEC's fivecorporate collaborations, are part-human, part Macaque monkey.They may be less immunogenic than murine-based antibodiesbecause the immunoglobulin of Macaques is closer to that of humans,IDEC said.

Ludvigson said IDEC is starting from scratch on the Primatizedantibody. IDEC and Eisai hope to file an investigational new drugapplication for the humanized version in 1997, he said.

IDEC's lead compound is IDEC-C2B8, which targets the CD20antigen expressed on the surface of mature B cells and B cell tumors.IDEC and collaborator Genentech Inc., of South San Francisco, arein Phase III studies of the antibody for treatment of relapsed low-grade and follicular non-Hodgkin's lymphomas.

IDEC's anti-CD4 antibody, IDEC-CE9.1, is in a Phase II rheumatoidarthritis trial being run by London-based SmithKline Beecham plc.Results are expected in the second half of 1996, Ludvigson said.

Another IDEC collaboration is with Seikagaku Corp., of Japan,focused on developing an antibody against the CD23 antigen oncertain white blood cells as treatment for allergic rhinitis, asthma andother allergenic conditions.

And the company's fifth collaboration is with Mitsubishi KaseiCorp., of Tokyo, to develop antibodies directed at the B7 marker oncertain immune system cells.

"We have a series of potential products targeted at a variety ofautoimmune diseases," Ludvigson said. "Gp39 fits in with the B7program and the CD4 program in that all three have different impactson the operation of the immune system.

"We've taken a technology we developed in the cancer area withC2B8 and leveraged it by changing the targets and introducing thePrimatized technology," Ludvigson said. Only the Genentechcollaboration doesn't involve Primatized antibodies.

The deal with Eisai means that, for the most part, IDEC has partneredthe programs in its pipeline. There still are radioconjugates and anadjuvant used in cancer, as well as a number of geographical areas inongoing partnerships where IDEC still has rights. n

-- Jim Shrine

(c) 1997 American Health Consultants. All rights reserved.