Quantification/surrogates of engrafted corrected HSCs proposed for use in measuring cure in SCD
| End point . | Measures . | Grade of Cure . |
|---|---|---|
| GT/E | VCN or edited cells and alleles in infusion product and 0.5, 1, 2, 5, 10, and 15 y after genetic modification (%); genetically modified and allele modified CFUc (%) | VCN in infused product and up to 6 mo after GT/E can be higher; stable VCN (at year 1 onward) that results in: |
| 1: 100% genetically corrected RBCs | ||
| 2: 75%-100% corrected RBCs | ||
| 3: 50%-75% corrected RBCs | ||
| 4: 25%-50% corrected RBCs | ||
| 5: 0%-25% corrected RBCs. | ||
| Corrected RBCs may be defined as antisickling Hb containing RBCs and/or RBCs that resist sickling (%) | ||
| Engraftment | Normal or genetically modified HSC chimerism (%) | 1: >50% |
| 2: >20% |
| End point . | Measures . | Grade of Cure . |
|---|---|---|
| GT/E | VCN or edited cells and alleles in infusion product and 0.5, 1, 2, 5, 10, and 15 y after genetic modification (%); genetically modified and allele modified CFUc (%) | VCN in infused product and up to 6 mo after GT/E can be higher; stable VCN (at year 1 onward) that results in: |
| 1: 100% genetically corrected RBCs | ||
| 2: 75%-100% corrected RBCs | ||
| 3: 50%-75% corrected RBCs | ||
| 4: 25%-50% corrected RBCs | ||
| 5: 0%-25% corrected RBCs. | ||
| Corrected RBCs may be defined as antisickling Hb containing RBCs and/or RBCs that resist sickling (%) | ||
| Engraftment | Normal or genetically modified HSC chimerism (%) | 1: >50% |
| 2: >20% |
CFUc, colony-forming units in culture.