By Charles Craig

Applied Immune Sciences Inc. has launched Phase III multicentertrials of its AIS CELLector CD5/CD8 device to prevent acute graft-versus-host-disease (GvHD) in allogenic bone marrow transplantsused to treat leukemia patients.

In addition, the Santa Clara, Calif.-based company has released datafrom a Phase II AIDS trial involving its CELLector. The resultsindicated that isolating HIV patients' CD 8 cells and activating themwith interleukin-2 may help reconstitute the body's immune systemto slow the progression of the virus.

Tom Okarma, CEO of Applied Immune Sciences, said the Phase IIIbone marrow transplant trials will be conducted at 12 sites in theU.S. and involve 160 patients, half of whom will receive treatmentwith the AIS CELLector.

GvHD occurs when T cells in donor bone marrow recognize therecipients' tissues as foreign and initiate an immune system attack,which causes rejection of the transplant. Typically, 50 percent ofallogenic bone marrow recipients develop acute GvHD and half ofthem die.

Applied Immune Sciences' CELLector is used to deplete CD5 andCD8 T cells from donor bone marrow before it is transplanted tothwart onset of GvHD. In addition to the specific T cell depletion,the donor's bone marrow is treated with conventional drugs used tobattle GvHD.

Okarma said the trials have two main clinical endpoints. The first isreduction in GvHD, which usually strikes within 100 days of thebone marrow transplant.

Results from Phase II studies showed that only two of 15 patients, or13 percent, developed acute GvHD after their donor bone marrowwas treated with the CELLector. The results also showed minimumdepletion of CD34+ cells, which are needed for revitalizing theblood and immune systems.

In the Phase II AIDS trials, the CELLector was used to isolate CD8cells from the peripheral blood of HIV patients. Once separated, thecells were activated with interleukin-2 and increased in numberbefore being re-infused in the patients.

Okarma said the data from the trials indicated that the re-infusedCD8 cells apparently triggered increased production of CD28 cells,which have been associated with slowing the progression of HIV toAIDS.

Applied Immune Sciences released data on the Phase II AIDS trialslast weekend and plans to present the results today at the SecondNational Conference On Human Retroviruses and Related Infectionsin Washington. n