Patient characteristics
| Characteristics . | Total (N = 184) . | Developmental cohort (n = 128) . | Validation cohort (n = 56) . | P value . |
|---|---|---|---|---|
| HLA match: 7/8 vs 8/8, n (%) | 42 (23) vs 142 (77) | 30 (23) vs 98 (77) | 12 (21) vs 44 (79) | .76 |
| Abatacept vs placebo, n (%) | 115 (63) vs 69 (38) | 83 (65) vs 45 (35) | 32 (57) vs 24 (43) | .32 |
| Age in y, median (range) | 44 (7-76) | 45 (7-76) | 40 (8-76) | >.99 |
| Age ≥21 y, n (%) | 134 (72) | 93 (73) | 41 (73) | .94 |
| Race, White, n (%) | 153 (83) | 109 (85) | 44 (79) | .27 |
| PS ≥ 90%, n (%) | 135 (73) | 96 (75) | 39 (70) | .45 |
| Disease, n (%) | .15 | |||
| AML | 67 (36) | 42 (33) | 25 (45) | |
| ALL | 56 (30) | 40 (31) | 16 (29) | |
| MDS | 37 (20) | 25 (20) | 12 (21) | |
| Other | 24 (13) | 21 (16) | 3 (5) | |
| CIBMTR disease stage, n (%) | .27 | |||
| Early | 110 (60) | 82 (64) | 28 (50) | |
| Intermediate | 43 (23) | 26 (20) | 17 (30) | |
| Advanced | 30 (16) | 19 (15) | 11 (20) | |
| Other | 1 (1) | 1 (1) | 0 | |
| Conditioning regimen, n (%) | .26 | |||
| Busulfan/cyclophosphamide | 61 (33) | 41 (32) | 20 (36) | |
| TBI/cyclophosphamide | 57 (31) | 43 (34) | 14 (25) | |
| Fludarabine/melphalan | 49 (27) | 30 (23) | 19 (34) | |
| Busulfan/fludarabine | 17 (9) | 14 (11) | 3 (5) | |
| Conditioning: MAC vs RIC, n (%) | 136 (74) vs 48 (26) | 99 (77) vs 29 (23) | 37 (66) vs 19 (34) | .11 |
| Patient CMV seropositive, n (%) | 79 (43) | 57 (45) | 22 (39) | .68 |
| Graft: BM vs PBSC, n (%) | 79 (43) vs 105 (57) | 54 (42) vs 74 (58) | 25 (45) vs 31 (55) | .76 |
| Characteristics . | Total (N = 184) . | Developmental cohort (n = 128) . | Validation cohort (n = 56) . | P value . |
|---|---|---|---|---|
| HLA match: 7/8 vs 8/8, n (%) | 42 (23) vs 142 (77) | 30 (23) vs 98 (77) | 12 (21) vs 44 (79) | .76 |
| Abatacept vs placebo, n (%) | 115 (63) vs 69 (38) | 83 (65) vs 45 (35) | 32 (57) vs 24 (43) | .32 |
| Age in y, median (range) | 44 (7-76) | 45 (7-76) | 40 (8-76) | >.99 |
| Age ≥21 y, n (%) | 134 (72) | 93 (73) | 41 (73) | .94 |
| Race, White, n (%) | 153 (83) | 109 (85) | 44 (79) | .27 |
| PS ≥ 90%, n (%) | 135 (73) | 96 (75) | 39 (70) | .45 |
| Disease, n (%) | .15 | |||
| AML | 67 (36) | 42 (33) | 25 (45) | |
| ALL | 56 (30) | 40 (31) | 16 (29) | |
| MDS | 37 (20) | 25 (20) | 12 (21) | |
| Other | 24 (13) | 21 (16) | 3 (5) | |
| CIBMTR disease stage, n (%) | .27 | |||
| Early | 110 (60) | 82 (64) | 28 (50) | |
| Intermediate | 43 (23) | 26 (20) | 17 (30) | |
| Advanced | 30 (16) | 19 (15) | 11 (20) | |
| Other | 1 (1) | 1 (1) | 0 | |
| Conditioning regimen, n (%) | .26 | |||
| Busulfan/cyclophosphamide | 61 (33) | 41 (32) | 20 (36) | |
| TBI/cyclophosphamide | 57 (31) | 43 (34) | 14 (25) | |
| Fludarabine/melphalan | 49 (27) | 30 (23) | 19 (34) | |
| Busulfan/fludarabine | 17 (9) | 14 (11) | 3 (5) | |
| Conditioning: MAC vs RIC, n (%) | 136 (74) vs 48 (26) | 99 (77) vs 29 (23) | 37 (66) vs 19 (34) | .11 |
| Patient CMV seropositive, n (%) | 79 (43) | 57 (45) | 22 (39) | .68 |
| Graft: BM vs PBSC, n (%) | 79 (43) vs 105 (57) | 54 (42) vs 74 (58) | 25 (45) vs 31 (55) | .76 |
AML, acute myeloid leukemia; ALL, acute lymphoblastic leukemia; BM, bone marrow, CIBMTR, the Center for International Blood and Marrow Transplant Research; MAC, myeloablative conditioning; MDS, myelodysplastic syndrome; PBSC, peripheral blood stem cell; PS, performance status; RIC, reduced intensity conditioning; TBI, total body irradiation.