- Almost one-half of patients with chronic myeloid leukemia (CML) who discontinued second- or subsequent-line dasatinib after achieving deep molecular response (DMR) maintained treatment-free remission (TFR) at 3 years.
- Imatinib-resistant patients were at greater risk for relapse.
Why this matters
- Data are scarce regarding the discontinuation of second-generation tyrosine kinase inhibitors (TKIs) as second-line therapy.
- Planned 3-year analysis of the phase 2 DADI (dasatinib discontinuation) trial in 63 patients receiving second- or subsequent-line dasatinib after achieving and maintaining DMR for ≥1 year.
- DMR was defined as a sample with <0.0069% BCR-ABL1 (also known as MR4.0).
- Funding: Bristol-Myers Squibb, Novartis.
- 44 (interquartile range, 40.5-48) months median follow-up.
- At 36 months:
- 44% (95% CI, 32.0%-56.2%) of patients maintained TFR.
- 8% (95% CI, 0%-29%) TFR in imatinib-resistant patients.
- In multivariate analysis, absence of imatinib resistance and higher cytolytic natural killer cell count prior to TKI discontinuation were independently associated with maintenance of TFR.
- Only 2 relapses were reported at 1 year.
- Single-arm study.
- Japanese study population; results may not necessarily extrapolate to other subpopulations.