1. Crossover for pts meeting ELN 2013 failure criteria
DAS vs IMA in pts with CML-CP who have not achieved an optimal response to 3 mo of IMA therapy: DASCERN
Cortes (Abstract # 788)
Oral
Objectives
To evaluate early switch to DAS vs remaining on IMA in pts with CML-CP who have not achieved an optimal response (ie, BCR-ABL1IS ≤ 10%) with 3 mo of 1L IMA treatment
DAS 100 mg QD
(n = 174)
R (2:1)
IMA ≥ 400 mg QD or BID
(n = 86)
Pts with CML-CP
Received 1L IMA 400 mg QD
Achieved CHR but BCR-ABL1IS > 10% at 3 mo
Crossover for pts meeting ELN failure criteria
F/up up to 6 mo after LPFV
Methods
Primary endpoint: MMR rate at 12 mo after day 1 initiation of 1L IMA (i.e., 9 mo after randomization)
Results
78% male; 73% Asian; median age, y; minimum f/up, ≥ 12 mo
At the time of analysis, 84% of pts were continuing in the study; 42 (49%) of IMA-randomized pts had crossed over to DAS
MMR rate at 12 mo was higher with DAS vs IMA
100
P=0.005
DAS (n=174)
IMA (n=86)
29%
13% 90 80 70 60 50 40 30 20 10
MMR at 12 months
MMR, % (95% CI)
MMR at 12 mo
1L, frontline; BID, twice daily; CML, chronic myeloid leukemia; CP, chronic phase; DAS, dasatinib; ELN, European LeukemiaNet; f/up, follow-up; IMA, imatinib; IS, International Scale; MMR, major molecular response (BCR-ABL1IS ≤ 0.1%); LPFV, last patient first visit; pt, patient; QD, once daily.

2. DAS vs IMA in pts with CML-CP who have not achieved an optimal response to 3 mo of IMA therapy: DASCERN
Cortes (Abstract # 788)
Oral
Results (cont)
Median time to MMR with DAS vs IMA: 14 vs 20 mo
Rate of MR4.5 at 12 mo: 5% with DAS vs 2% with IMA
No differences between DAS and IMA were seen in PFS (96.9% vs 97.6%) or OS (98.8% for both)
No new safety signals were seen with DAS or IMA, and early switch to DAS did not increase toxicity rates
Rates of treatment-emergent pleural effusion were 5% in DAS-randomized pts (1 case was grade 3) and 7% in IMA-randomized pts who crossed over to DAS (1 case was grade 4 and the pt discontinued from the study)
Time to MMR
1.0
0.8
0.6
0.4
0.2 3 6 9 12 15 18 21 24 30 36 42 48 54
Pts at risk
Time Since Randomization (mo)
Probability of MMR
DAS
IMA
172 86
156 82
128 75
107 67 79 58 59 45 35 32 22 28 20 14 7 2 1
Authors Conclusions
In pts with suboptimal responses to IMA at 3 mo, switching to DAS provided a significantly higher rate of MMR at 12 mo vs remaining on IMA
Longer f/up is needed to evaluate the impact of early switch on PFS, OS, and deep molecular responses
CML, chronic myeloid leukemia; CP, chronic phase; DAS, dasatinib; f/up, follow-up; IMA, imatinib; IS, International Scale; MMR, major molecular response (BCR-ABL1IS ≤ 0.1%); MR4.5, BCR-ABL1IS ≤ %; OS, overall survival; PFS, progression-free survival; pt, patient.