Patient characteristics who received CD34+-selected SCB
| Patient characteristics, n = 7 | ||
| Median age, y | ||
| At initial diagnosis of B-ALL | 6 | Range, 1-23 |
| At SCT | 14 | Range, 7-24 |
| At CAR-T therapy | 15 | Range, 10-27 |
| Baseline characteristics pre CAR T-cell therapy | ||
| Previous SCT | 7 | — |
| Relapses, ≥2 | 6 | — |
| CAR T-cell therapy characteristics, n = 7 | ||
| CARPALL study (#NCT02443831) | 3 | Autologous CD19 directed |
| 1 | Autologous CD19/CD22 directed | |
| AMELIA study (#NCT03289455) | 1 | Autologous CD19/CD22 directed |
| CARD study (#NCT02893189) | 1 | Allogenic CD19 directed |
| Tisagenlecleucel (licensed product) | 1 | Autologous CD19 directed |
| Post–CAR T-cell therapy, n = 7 | ||
| CRS | 4 | Grade 1, n = 1; Grade 2, n = 2; Grade 3, n = 1 |
| ICANS | 3 | Grade 3, n = 1; Grade 4, n = 2 |
| Median time to CD34+ SCB infusion after CAR-T therapy, mo | 2.6 | Range, 1.9-16.5 |
| Median Age at CD34 SCB, y | 16 | Range, 11-27 |
| Pre-CD34+–selected SCB, n = 7 | ||
| Cytopenias, n | ||
| Pancytopenia | 6 | — |
| Bicytopenia | 1 | — |
| MRD negativity, n | 7 | MRD method: molecular n=2, flow n=3, both n=2 |
| Chimerism (data available on 5/7 patients), n* | ||
| Full donor | 4 | |
| Mixed | 1 | |
| Infections | ||
| Invasive fungal infection | 3 | — |
| Viral infection(s) | 1 | — |
| Bacterial infection(s) | 1 | — |
| CD34+-selected SCB characteristics, n = 7 | ||
| Median dose, per kg | ||
| CD34+ cells | 6.75 × 106 | Range, 2.5-11.2 × 106 |
| CD3+ T cells | 0.19 × 104 | Range, 0.07-1.22 × 104 |
| Toxicities after CD34 stem-cell infusion, n = 7 | ||
| CRS† | 1 | — |
| ICANS | 0 | — |
| GVHD (acute or chronic) | 0 | — |
| Response to CD34 SCB‡ | ||
| Median time to recovery, d | ||
| Neutrophils >1 × 109/L without GCSF | 42 | Range, 11-192 |
| Blood transfusion independent | 33 | Range 4-106 |
| Platelet transfusion independent | 33 | Range 7-73 |
| Status at last follow-up§ | ||
| Deceased | ||
| Relapse | 2 | |
| Infection related | 2 | |
| Further therapy related | 1 | |
| Alive‖ | 2 | |
| Patient characteristics, n = 7 | ||
| Median age, y | ||
| At initial diagnosis of B-ALL | 6 | Range, 1-23 |
| At SCT | 14 | Range, 7-24 |
| At CAR-T therapy | 15 | Range, 10-27 |
| Baseline characteristics pre CAR T-cell therapy | ||
| Previous SCT | 7 | — |
| Relapses, ≥2 | 6 | — |
| CAR T-cell therapy characteristics, n = 7 | ||
| CARPALL study (#NCT02443831) | 3 | Autologous CD19 directed |
| 1 | Autologous CD19/CD22 directed | |
| AMELIA study (#NCT03289455) | 1 | Autologous CD19/CD22 directed |
| CARD study (#NCT02893189) | 1 | Allogenic CD19 directed |
| Tisagenlecleucel (licensed product) | 1 | Autologous CD19 directed |
| Post–CAR T-cell therapy, n = 7 | ||
| CRS | 4 | Grade 1, n = 1; Grade 2, n = 2; Grade 3, n = 1 |
| ICANS | 3 | Grade 3, n = 1; Grade 4, n = 2 |
| Median time to CD34+ SCB infusion after CAR-T therapy, mo | 2.6 | Range, 1.9-16.5 |
| Median Age at CD34 SCB, y | 16 | Range, 11-27 |
| Pre-CD34+–selected SCB, n = 7 | ||
| Cytopenias, n | ||
| Pancytopenia | 6 | — |
| Bicytopenia | 1 | — |
| MRD negativity, n | 7 | MRD method: molecular n=2, flow n=3, both n=2 |
| Chimerism (data available on 5/7 patients), n* | ||
| Full donor | 4 | |
| Mixed | 1 | |
| Infections | ||
| Invasive fungal infection | 3 | — |
| Viral infection(s) | 1 | — |
| Bacterial infection(s) | 1 | — |
| CD34+-selected SCB characteristics, n = 7 | ||
| Median dose, per kg | ||
| CD34+ cells | 6.75 × 106 | Range, 2.5-11.2 × 106 |
| CD3+ T cells | 0.19 × 104 | Range, 0.07-1.22 × 104 |
| Toxicities after CD34 stem-cell infusion, n = 7 | ||
| CRS† | 1 | — |
| ICANS | 0 | — |
| GVHD (acute or chronic) | 0 | — |
| Response to CD34 SCB‡ | ||
| Median time to recovery, d | ||
| Neutrophils >1 × 109/L without GCSF | 42 | Range, 11-192 |
| Blood transfusion independent | 33 | Range 4-106 |
| Platelet transfusion independent | 33 | Range 7-73 |
| Status at last follow-up§ | ||
| Deceased | ||
| Relapse | 2 | |
| Infection related | 2 | |
| Further therapy related | 1 | |
| Alive‖ | 2 | |
N = 7 patients.
ICANS, immune effector cell–associated neurotoxicity syndrome; MRD minimal residual disease.
Of the 4/7 pts who responded to SCB, data were unavailable in 1 patient, 2 had full donor chimerism, 1 had mixed chimerism (WB 82%, CD3 95%, CD15 31%) pre-SCB.
Treated with methylprednisolone and siltuximab.
Two patients died, 1 at day 24 and 1 at day 38. One patient had transient recovery of bicytopenia followed by ongoing cytopenias until death. Response data shown depicts hematological recovery for the remaining 4 evaluable patients..
After CD34 stem-cell boost (median, 9 mo; range, 24 d–2.5 y).
Both patients in CR and with complete hematological recovery at last follow-up.