EHA 2017: Half of Chronic-Phase Philadelphia Chromosome–Positive CML Patients Stay in Treatment-Free Remission 2 Years After Stopping Nilotinib
New data from two clinical trials—ENESTfreedom and ENESTop—demonstrates that approximately half of adult patients with Philadelphia chromosome–positive chronic myeloid leukemia (CML) in the chronic phase, were able to maintain treatment-free remission after stopping treatment with nilotinib (Tasigna) both in the first-line setting and after switching from imatinib. The studies were presented at the 2017 Congress of the European Hematology Association (EHA) in Madrid (Abstracts P601, P257).
ENESTfreedom
Results from the ENESTfreedom 96-week update found that nearly half of the 190 patients with CML (48.9%, 95% confidence interval [CI] = 41.6%–56.3%) who entered treatment-free remission, following at least 3 years of first-line treatment with nilotinib (and with a sustained deep molecular response for 1 year prior to stopping), remained in major molecular response (BCR-ABL1 International Scale [IS] ≤ 0.1%) and off treatment at week 96, including 88 patients (46.3%) who were in deep molecular response. Among patients remaining in treatment-free remission for more than 48 weeks (n = 100), fewer adverse events were experienced during the second 48 weeks compared to the first 48-week period. Rates of musculoskeletal pain-related adverse events were 34% and 9% during the first and second 48-week periods, respectively. These results suggest a reduction in adverse events the longer the patient is in treatment-free remission.
ENESTop
Updated 96-week data from ENESTop evaluated treatment-free remission in 126 patients who previously switched from imatinib to nilotinib and subsequently achieved a sustained deep molecular response. At week 96, 53.2% of the patients who entered treatment-free remission remained so (95% CI = 44.1%–62.1%). Among patients who remained in treatment-free remission for more than 48 weeks (n = 73), rates of adverse events were 82.2% and 63.0% during the first and second 48-week period of treatment-free remission, respectively. Rates of musculoskeletal pain-related adverse events were 47.9% and 15.1% during the first and second 48-week period of treatment-free remission, respectively.
Commentary
The approval by the European Commission to update the nilotonib Summary of Product Characteristics was based on efficacy and safety findings from the 48-week analyses of ENESTfreedom and ENESTop, which showed that more than 50% of chronic-phase Philadelphia chromosome–positive CML patients who met the rigorous predefined response criteria of the trials were able to maintain treatment-free remission after stopping nilotinib in both in the first-line setting and after switching from imatinib.
Adam Mead, MRCP, FRCPath, Associate Professor of Hematology at the Weatherall Institute of Molecular Medicine of the University of Oxford, said, “The findings from these two trials … demonstrating stability of the treatment-free remission rate between 48 and 96 weeks, provides further evidence of the durability of molecular response following discontinuation of tyrosine kinase inhibitor treatment in certain patients with CML. This is a significant milestone, supporting that we can now consider stopping treatment in carefully selected patients with this chronic condition.”
Barak Palatchi, Oncology General Manager, Novartis UK & Ireland, said, “The possibility for many patients to become treatment-free is a huge step forward in the management of CML.… [It has helped] transform this disease from a fatal leukemia to a chronic condition for a majority of patients.”
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
