Treatment-free remission with first- and second-generation tyrosine kinase inhibitors

Chronic myeloid leukemia (CML) has become a chronic disease, for which the chronic phase is manageable with tyrosine kinase inhibitor (TKI) therapy. Patients with optimal responses to TKIs have achieved long-term survival, and treatment-free remission (TFR) has since become an additional treatment goal in CML. In this review, we discuss important factors to consider prior to stopping treatment. In addition, published and presented data with the first-generation TKI imatinib, as well as current clinical trials evaluating TFR with the second-generation TKIs dasatinib and nilotinib, are examined. Results obtained outside of clinical trials have been included as well. Because successful TKI discontinuation depends upon accurate BCR-ABL1 monitoring, emerging technologies are also discussed. Clinical data obtained to date indicate that for many patients who achieve deep molecular response (DMR) on TKI therapy, TFR is a safe treatment goal, and, if the response is lost, patients can expect to regain their responses immediately upon reinitiation of TKI. It is also clear that there remains much room for improvement to make TFR a successful reality for most patients. Data from ongoing trials should help refine decisions as to which patients are the best candidates to attempt TKI discontinuation with safe monitoring in place.

Treatment-Free Remission in CML: the US Perspective

PURPOSE OF REVIEW

Chronic myeloid leukemia (CML) patients treated with tyrosine kinase inhibitors (TKI) have near-normal life expectancy. However, lifelong TKI therapy is associated with reduced quality of life and significant economic burden. Currently, the management of CML is shifting from continuous TKI therapy towards the goal of TKI cessation which is discussed in this review.

RECENT FINDINGS

Several studies in the last decade have demonstrated the feasibility and safety of TKI discontinuation in selected patients with CML who achieve deep and sustained molecular response with TKI. This has moved prime-time into clinical practice although open questions remain in terms of understanding the disease biology that leads to successful TKI cessation in some patients while not in others. Cessation of TKI for CML patients is a feasible approach. Ongoing research aims to find out optimal strategies to sustain ongoing treatment-free remission (TFR) and increase the number of patients who achieve TFR.