Washington Editor

Poor preliminary data from two Phase II trials of Vitaxin in rheumatoid arthritis and psoriasis prompted MedImmune Inc. to terminate development in those inflammatory diseases.

Wall Street was fairly accepting, as MedImmune's stock (NASDAQ:MEDI) fell by just 73 cents to close at $23.76.

Meanwhile, MedImmune's oncology program for Vitaxin is ongoing, Jamie Lacey, MedImmune's director of media and public relations, told BioWorld Today. There were no safety concerns identified in inflammatory trials.

Vitaxin is the subject of Phase II trials in melanoma and prostate cancer, Lacey said, adding that MedImmune hopes to enter pivotal trials in 2005.

The rheumatoid arthritis (RA) trial included 300 people and the psoriasis trial had 180 patients. Lacey would not say when final data will be ready for release, and she wouldn't comment on specifics related to the decision to stop development in the indications, although the company said that "preliminary data suggest a lack of clinic benefit in inflammatory diseases."

Vitaxin targets the alpha-v beta-3 integrin, which is a protein expressed on the surface of newly forming blood vessels, certain tumor types and on a number of other cell types, including macrophages and osteoclasts. Based on preclinical models, the alpha-v beta-3 integrin has been implicated in a number of disease processes, including the growth and metastasis of tumors (as well as the bone destruction in RA and the inflammatory process in psoriasis), the company said.

MedImmune, of Gaithersburg, Md., in 1999 acquired rights to Vitaxin from Applied Molecular Evolution Inc., the San Diego-based firm that optimized the monoclonal antibody.

In other business at MedImmune, the company is poised to begin sales for the second flu season of FluMist, an intranasal influenza virus vaccine live. Months after FluMist's first season, MedImmune reacquired all rights to the drug from partner Wyeth, of Madison, N.J. (See BioWorld Today, April 28, 2004.)

MedImmune inherited FluMist and the Wyeth collaboration when it acquired Mountain View, Calif.-based Aviron Inc. in January 2002. FluMist was approved in June 2003 and made $31 million in its first season, 2003 to 2004. (See BioWorld Today, June 18, 2003.)

With the loss of Wyeth, MedImmune selected the firm Henry Schein, of Melville, N.Y., to exclusively distribute FluMist for the upcoming season. As part of the deal signed in June, MedImmune will oversee all sales and marketing activities with special emphasis on pediatricians and pharmacies. Henry Schein will respond to customer product inquiries, process returns and promote the product through marketing initiatives to primary care physicians.

Lacey said the partners intend to manufacture between 1 million and 2 million doses for the 2004-2005 flu season, and expect sales to equal those of last year (the company sold 450,000 doses in the 2003-2004 flu season).

"We have indicated that we don't believe FluMist will be a meaningful contributor to our bottom line until at least 2007," she said.

Sales are expected to pick up once the FluMist label is expanded to include children less than 5 years of age, and adults 50 to 64 years of age. MedImmune is running trials to support an expansion request.

MedImmune also is developing CAIV-T - Cold Adapted Influenza Vaccine-Trivalent - a second-generation liquid formulation of FluMist that could be the subject of a U.S. regulatory filing in 2006. Previous Phase III studies of the refrigerator-stable product showed statistically superior efficacy over a traditional flu shot in preventing culture-infirmed influenza in children.