Outcomes were assessed for 89 patients (median age = 46) with hématologie malignancies enrolled in a multi-site Phase II study of transplants from HLA identical family members using PBSC enriched for CD34+ cells and depleted of T-cells using the Isolex®300i System. Eighty-seven patients received transplants, 82 with positively selected CD34+ cells and five with unselected back-up due to poor mobilization/low CD34 counts in the donor products. Patients were conditioned using institutional regimens; GVHD prophylaxis varied, but generally was without methotrexate. The median doses of CD34+ and CD3+ cells were 5.7 x 106/kg and 1.3 x lOVkg, respectively in patients transplanted with selected cell products. Median time to neutrophil (500/uL) and platelet engraftment (20,000/nL) was 13 days for both. Follow-up ranges from 5-36 months (median 6.3 months). There were no primary or secondary graft failures. Chimerism assessed in 33 cases indicated that engrafted cells were donor in origin. Thirty and 100-day mortality rates were 8% and 28% respectively for all patients; for patients with CML (n=21) the rates were 5 and 10%, and for patients with AML (n=22), 0 and 36%. Severe acute GVHD (grades III-IV) was reported in 9/84 (10%) évaluable patients. Sixteen relapses have been reported, including 7/21 CML patients. Of these seven, two were reported to be in accelerated phase at the time of transplant, two in blast crisis, one with progressive disease, and two in chronic phase (cytogenetic relapses). There have been 38 (48%) reported deaths, including 8 (9%) from progressive disease, 17 (20%) associated with infections, and 13 (15%) associated with other treatment related toxicities. The data support the conclusion that T-cell depletion by positive selection provides transplant products that support rapid and durable engraftment. The low rate of severe aGVHD coupled with the absence of graft failure and acceptable relapse rate provide the basis for an ongoing randomized Phase III study comparing MTX & CSA vs T cell depletion (positive selection using Isolex®300i) & CSA for GVHD prophylaxis in recipients of transplants from matched related donors.
|Original language||English (US)|
|Issue number||11 PART I|
|State||Published - Dec 1 2000|
ASJC Scopus subject areas
- Cell Biology