LONDON - Celltech plc, of Slough, U.K., has been granted fast-track designation by the FDA for CDP 571, currently in Phase IIb for the treatment of Crohn's disease. The compound, a humanized monoclonal antibody, is in two double-blind, placebo-controlled studies in the U.S., expected to recruit 210 patients.

Celltech has been told these can serve as pivotal studies. If the trials are successful, the company says it will apply for marketing approval in 2000.

The rights to CDP 571 were handed back to Celltech after it failed in a Phase III trial in septic shock carried out by Bayer AG, of Leverkusen, Germany. Bayer invested US$150 million on trials of the compound, which was then designated BAYX-1351.

This is Celltech's second compound in pivotal studies in the U.S. The company expects partner American Home Products Corp., of Madison, N.J., to file a new drug application for CMA676 for the treatment of acute myeloid leukemia in the first half of 1999. Interim Phase III study results in 23 patients, reported earlier this year, showed 43 percent experienced major responses, characterized by complete clearance of leukemic cells. There were no safety problems. The study, at 15 U.S. centers, is being conducted in patients who have relapsed following first remission.

Celltech also has had good news from licensees of its Boss patent, which covers technology used in the production of genetically engineered antibodies. In the first week of this month, Genentech Inc., of South San Francisco, won approval for Herceptin as a treatment for metastatic breast cancer, bringing to seven the number of approved products based on the Boss technology. Just a week earlier, Centocor Inc., of Malvern, Pa., received approval for Remicade in the treatment of Crohn's disease, which also draws on the Boss technology. *