Molecular characterization and predictors of relapse in patients with Ph + ALL after frontline ponatinib and blinatumomab

Table 1 Baseline characteristics and response rates of the study population (n = 76)

Baseline characteristics	n/N (%) / median [range]
Age (years)	50 [18–83]
Age ≥ 60 years	28 (37)
Baseline cardiovascular risk factor¹	40 (53)
WBC at diagnosis (x10⁹/L)	15.4 [0.6-322.1]
WBC at diagnosis ≥ 70 x10⁹/L	17 (22)
Central nervous system involvement at diagnosis	3 (4)
CD19 expression (%)	99.8 [74.9–100]
Additional chromosomal abnormalities	37/52 (71)
BCR::ABL1 transcript
p190	60/75 (80)
p210	15/75 (20)
Gene mutations
IKZF1	5/57 (9)
ASXL1	3/57 (5)
DNMT3A	3/57 (5)
TET2	3/57 (5)
BCORL1	1/57 (2)
ETV6	1/57 (2)
RUNX1	1/57 (2)
SF3B1	1/57 (2)
Gene deletions
IKZF1	35/48 (73)
CDKN2A/B	27/48 (56)
PAX5	13/48 (27)
XBP1	13/48 (27)
RB1	11/48 (23)
BTG1	7/48 (15)
VPREB1	7/48 (15)
CD200	5/48 (10)
IZKF1^plus genotype²	25/48 (52)
Response rates	n/N (%)
Hematologic response³
CR	51/53 (96)
CRi	1/53 (2)
Early death	1/53 (2)
MRD response⁴
CMR after cycle 1	41/69 (59)
CMR at any time	57/68 (83)
NGS MRD negative after cycle 1	17/36 (47)
NGS MRD negative at any time	55/57 (96)

Abbreviations: WBC, white blood cell count; CR, complete remission; CRi, complete remission with incomplete hematologic recovery; MRD, measurable residual disease; CMR, complete molecular response; NGS, next-generation sequencing
¹ Risk factors include: hypertension, hyperlipidemia, diabetes and/or coronary artery disease
² Includes patients with an IKZF1 deletion or IKZF1 frameshift mutation in combination with a CDKN2A/B and/or PAX5 deletion
³ Excludes patients who were in morphological remission at the time of enrollment
⁴ Excludes patients who were MRD-negative at the time of enrollment

ISSN: 1756-8722