TABLE 2.
Risk and Transplant Characteristics by Treatment Assignment
| Risk Factors & HCT Characteristics | Arm A: Busulfan-Cyclophosphamide-Melphalan (N = 6) | Arm B: Busulfan-Fludarabine (N = 9) |
|---|---|---|
| High-Risk Clinicallyˆ | 3 (50%) | 7 (78%) |
| Age >2 years at Diagnosis | 1 (16%) | 4 (44%) |
| Platelets <40 × 109/L at Diagnosis | 2 (33%) | 4 (44%) |
| Hemoglobin F elevated for age | 2 (33%) | 6 (67%) |
| High-Risk Biologically* | 2 (33%) | 6 (67%) |
| Cytogenetic Abnormality | 1 (16%) | 2 (22%) |
| Secondary Mutations | 1 (16%) | 3 (33%) |
| DNA Methylation (Intermediate or High) | 2 (33%) | 5 (63%)1 |
| Time from Diagnosis to HCT (range) | 1.4 months (0.7–3.5 months) |
1.2 months (0.5–3.7 months) |
| Pre-HCT Therapy | ||
| None | 2 (66%) | 4 (45%) |
| Low-Dose | 4 (67%) | 3 (33%) |
| AML-Like | 0 | 2 (22%) |
| Median Pre-HCT Allele Burden (range) | 39.4% (23%-46.8%) | 46.9% (0–50.3%) |
| Donor | ||
| HLA-Matched Related | 2 (33%) | 3 (33%) |
| 8/8 HLA-Matched Unrelated | 3 (50%) | 5 (56%) |
| <8/8 HLA-Mismatched Unrelated | 1 (16%) | 1 (11%) |
| Stem Cell Source | ||
| Bone Marrow | 6 (100%) | 7 (78%) |
| Peripheral Blood | 0 | 1 (11%) |
| Umbilical Cord Blood | 0 | 1 (11%) |
| Busulfan Cumulative AUC (mg*h/L) | 71 (58–87) | 68 (62–80) |
ˆ
Defined as the presence of at least 1 of the following: a) age >2 years at diagnosis; b) platelets <40 × 109/L at diagnosis; c) hemoglobin F elevated for age
*
Defined as presence of at least 1 of the following: a) cytogenetic abnormality; b) secondary mutation; or c) DNA Methylation Intermediate or High
1
Of 8 patients tested