Table 1.
CD19-positive relapse (N = 14) | CD19-negative relapse (N = 4) | |
---|---|---|
Sex, n (%) | ||
Male | 10 (71) | 2 (50) |
Female | 4 (29) | 2 (50) |
Geographic region, n (%) | ||
European Union | 6 (43) | 4 (100) |
United States | 8 (57) | 0 (0) |
Age, median (range), years | 6 (1–17) | 8 (5–12) |
Age group, n (%) | ||
<2 years | 3 (21) | 0 |
2–6 years | 6 (43) | 2 (50) |
7–17 years | 5 (36) | 2 (50) |
Genetic abnormalities, n (%) | ||
MLL total | 9 (64) | 1 (25) |
MLL-AF4 t(4, 11) | 2 (14) | 0 |
Other MLL | 6 (43) | 1 (25) |
BCR-ABL | 0 (0) | 0 (0) |
Hypodiploidy | 1 (7) | 0 (0) |
Constitutional trisomy 21 | 1 (7) | 0 (0) |
Previous alloHSCT, n (%) | ||
Yes | 9 (64) | 1 (25) |
No | 5 (36) | 3 (75) |
Previous relapses, n (%) | ||
1 | 4 (29) | 1 (25) |
2 | 8 (57) | 2 (50) |
≥3 | 2 (14) | 1 (25) |
Refractory disease, n (%) | 14 (100) | 4 (100) |
Yes | 0 (0) | 0 (0) |
No | 14 (100) | 4 (100) |
Time between last relapse and first blinatumomab infusion, median (range), months | 0.9 (0.1–10.2) | 0.8 (0.3–2.3) |
Relapse within 6 months after last prior treatment attempt, n (%) | 4 (29) | 2 (50) |
Bone marrow blast count (central laboratory), n (%) | ||
<50% | 6 (43) | 1 (25) |
≥50% | 8 (57) | 3 (75) |
alloHSCT allogeneic hematopoietic stem cell transplantation; BCR-ABL breakpoint cluster region-Abelson murine leukemia viral oncogene homolog 1 gene; MLL mixed-lineage leukemia gene. aFlow data from one patient was unavailable