Protein Design Labs Inc.'s humanized monoclonal antibodyanti-Tac-H inhibits tissue graft rejection in primates.
The National Cancer Institute, PDL and F. Hoffmann-La RocheInc.scientists reported in this month's Proceedings of theNational Academy of Sciences that anti-Tac-H promoted thesurvival of a cardiac graft in monkeys for 20 days. Untreatedmonkeys rejected cardiac grafts in 9.2 days, whereas monkeystreated with the mouse monoclonal antibody anti-Tac-Mrejected the graft within 14 days.
The scientists also showed that anti-Tac-H survived 2.5 timesas long as anti-Tac-M and was much less antigenic.
Anti-Tac-H and anti-Tac-M bind only to those IL-2 receptorson T cells that mount an immune response to foreign tissuesand organs. PDL converted anti-Tac-M into anti-Tac-H byreplacing more than 90 percent of the mouse monoclonalantibody with human sequences.
Hoffmann-La Roche, which has licensed anti-Tac-H from theMountain View, Calif.-based PDL, expects to begin clinical trialsthis fall, said Katherine Ku, PDL vice president of businessdevelopment.
In the same issue, PDL and University of Alabama, Birmingham(UAB), scientists described the humanizing of antibodies thatprotect cells from herpes simplex virus (HSV) infection. Ku toldBioWorld that animal studies of two humanized HSV antibodieshave begun at UAB and that PDL expects to begin clinical trialsof these antibodies by 1993.
-- Carol Talkington Verser, Ph.D. Special to BioWorld
(c) 1997 American Health Consultants. All rights reserved.