In chronic myeloid leukemia patients on second-line tyrosine kinase inhibitor therapy, deep sequencing of BCR-ABL1 at the time of warning may allow sensitive detection of emerging drug-resistant mutants

Table 1 Patients’ characteristics

Pts, total	51
CP CML	33
AP/BC CML	18
- with baseline IM-resistant mutations	29
- who acquired DAS-resistant mutations	26
T315I	13
F317L/V	10
V299L	3
- who acquired NIL-resistant mutations^a	25
E255K/V	9
F359V/I/C	7
Y253H	6
T315I	4
Median time on 2nd-line therapy, months (range)	9 (3–27)

Abbreviations: CP chronic phase (at the time of second-line TKI therapy start), AP/BC, accelerated phase or blast crisis (at the time of second-line TKI therapy start), IM imatinib, DAS dasatinib, NIL nilotinib, the ^a denotes that one patient had two mutations

ISSN: 1471-2407