MedImmune Inc. expanded its oncology pipeline after licensing North American rights to a clinical candidate from a German company, while at the same time taking an equity stake in the privately held firm.

MedImmune agreed to jointly develop a new class of antibody derivatives with Micromet AG, a deal initially focused on MT103, the lead candidate from Micromet's BiTE (bi-specific T-cell engagers) product platform. Both parties agreed to create up to six more candidates using the same platform.

"This fits into MedImmune's strategy to further build out our oncology portfolio," Jamie Lacey, MedImmune's associate director of public relations, told BioWorld Today. "Early stage clinical trials are scheduled to begin next year."

Munich-based Micromet has begun two Phase I studies in Europe of the B-cell tumor drug in non-Hodgkin's lymphoma and plans to begin a Phase I trial in chronic lymphocytic leukemia later this year. It retains rights to MT103 outside North America, an upside Micromet CEO Erich Felber called important to the company that began its drug development efforts in 1996. Micromet has raised €77 million since that point.

Though the deal's entire worth was not disclosed, Gaithersburg, Md.-based MedImmune is responsible for MT103's clinical development, registration and commercialization in North America, and will make unspecified milestone payments to Micromet based on development, filing, registration and marketing efforts related to the compound, as well as royalties. Also, MedImmune Ventures Inc., a wholly owned venture capital subsidiary of MedImmune, will make an undisclosed investment in Micromet.

MedImmune will develop the commercial manufacturing process and supply clinical trial material as well as commercial products for all markets.

The compound is designed to direct and activate a patient's T cells against tumor cells, targeting the CD19 antigen protein, which is present on the majority of B cells but not on other types of blood cells or healthy tissues.

"This compound enables a novel mode of action," Felber told BioWorld Today. "MedImmune is committed to building an oncology pipeline, and that kind of commitment from a partner that has all the capabilities and financial strength they have makes MedImmune an ideal partner."

MedImmune added that MT103 could have applications in autoimmune diseases such as rheumatoid arthritis, myasthenia gravis and systemic lupus erythematosus. But MedImmune's clinical trials will focus on the cancer indications, Lacey said.

Down the road, the partners expect to jointly develop additional compounds based on the BiTE platform, for which Micromet would receive milestones and royalties on sales. Micromet also retains an option for exclusive European rights to BiTE compounds based on targets not belonging to MedImmune and the option to receive co-promotion rights in Europe for BiTE compounds based on MedImmune's targets. Micromet is responsible for creating the new molecules, though MedImmune will cover full development costs up to Phase I for each. The parties said they expect to begin the first joint program within six months.

Lacey said MedImmune's interest in the BiTE technology fits with a desire to bring in more drug development know-how and invest in its future through its venture capital arm.

Micromet has drawn similar interest from prior partners as well. More than a year ago, the company entered a deal with Piscataway, N.J.-based Enzon Inc. focused on single-chain antibody therapeutics. (See BioWorld Today, April 12, 2002.)

Last September, Micromet entered an agreement with Bresso, Italy-based Novuspharma SpA to develop MT201, Micromet's fully human antibody that targets the Ep-CAM molecule. They planned to pursue a Phase II program with up to 1,000 patients in major cancer indications.

MedImmune's cancer division includes a number of other in-licensed products as well. It already markets Ethyol (amifostine) as a protective agent to reduce toxicities associated with certain cancer chemotherapy and radiotherapy treatments. It acquired the product through its 1999 purchase of U.S. Bioscience Inc.

In the pipeline, the investigational monoclonal antibody Vitaxin remains in clinical cancer studies as well as studies for rheumatoid arthritis. MedImmune acquired its rights in 1999 from Applied Molecular Evolution Inc. The company is conducting a preclinical evaluation of siplizumab (MEDI-507) in T-cell lymphoma. The monoclonal antibody remains in Phase II studies for psoriasis.

MedImmune, which in 2001 began to expand its oncology franchise, has in-licensed various preclinical technologies in recent years as well. In October 2001, it gained worldwide rights to EphA2 technology from Purdue Research Foundation, which could produce compounds to treat aggressive tumors and prevent metastasis.

A little more than a year ago, the company gained exclusive worldwide rights to two other early stage technologies. From Gaithersburg-based Panacea Pharmaceuticals Inc., MedImmune acquired rights to the enzyme human aspartyl (asparaginyl) beta-hydroxylase (HAAH), for which preclinical findings indicated that overexpression induces tumor formation. From Baltimore-based A&G Pharmaceuticals Inc., it received rights to technology targeting PC-cell-derived growth factor, which is expressed by breast cancer cells that respond to estrogen therapies and those resistant to estrogen therapies. (See BioWorld Today, April 22, 2002.)

MedImmune's stock (NASDAQ:MEDI) dropped $1.04 Monday to close at $38.