Partially T-cell-depleted allogeneic stem-cell transplantation for first-line treatment of multiple myeloma: a prospective evaluation of patients treated in the phase III study HOVON 24 MM.
OBJECTIVE
To determine in a prospective study the efficacy, toxicity, and long-term outcome of up-front allogeneic stem-cell transplantation (allo-SCT) in multiple myeloma (MM).


METHODS
In the prospective phase III study by the Dutch-Belgian Hemato-Oncology Cooperative Group (HOVON), HOVON 24 MM, 53 patients with an HLA-identical sibling (median age at transplantation, 48 years; range, 31 to 56 years) were allocated to a partial T-cell-depleted allo-SCT after induction therapy.


RESULTS
The overall response rate after allo-SCT was 89% (47 of 53 patients), including the 19% of patients (10 of 53 patients) with a complete remission (CR). Five patients achieved a CR only after allo-SCT. Five (71%) of seven primary refractory patients obtained a response to allo-SCT, all of whom had a partial remission. With a median follow-up of 38 months (range, 25 to 61 months), 20 patients are alive since allo-SCT and 33 patients have died (14 from progressive disease, 18 from treatment-related mortality [TRM], and one from another cause). Occurrence of acute graft-versus-host disease grades 2 to 4 predicted for higher TRM in a time-dependent analysis. The median progression-free survival time after allo-SCT was 17 months. Median overall survival time after allo-SCT was 25 months, or 29 months from the start of therapy. Only three patients are in continuing CR, indicating that the potential cure rate of this approach is, at best, 6%.


CONCLUSIONS
This first prospective evaluation of up-front allo-SCT of MM in a multicenter setting does not support the use of T-cell-depleted myeloablative allo-SCT as part of first-line therapy.
Lokhorst
Henk M
HM
Department of Hematology, University Medical Center Utrecht, HP G03.647, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands. H.Lokhorst@azu.nl
Segeren
Christine M
CM
Verdonck
Leo F
LF
van der Holt
Bronno
B
Raymakers
Reinier
R
van Oers
Marinus H J
MH
Barge
Renee M Y
RM
Schouten
Harry C
HC
Westveer
Petra H M
PH
Steijaert
Monique M C
MM
Cornelissen
Jan J
JJ
Sonneveld
Pieter
P
D000328:Adult; D005260:Female; D006801:Humans; D008212:Lymphocyte Depletion; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000473:pathology / Q000628:therapy*; D036102:Peripheral Blood Stem Cell Transplantation; D011446:Prospective Studies; D013534:Survival; D013601:T-Lymphocytes; D014184:Transplantation, Homologous; D016896:Treatment Outcome