After 2 years of consolidation treatment, patients with chronic myeloid leukemia (CML) who had achieved sustained deep molecular response were able to successfully discontinue treatment with the tyrosine kinase inhibitor (TKI) nilotinib, according to the results of the Japanese STAT2 trial.1 At 3 years, more than 6 in 10 patients remained treatment-free after successfully completing 2 years of consolidation therapy with nilotinib.
These results echo those of the STIM1 study, which showed that patients with CML who had undetectable minimal residual disease for at least 2 years could successfully stop treatment with the TKI imatinib.2In STIM1, however, molecular recurrence-free survival was only 43% at 2 years.
According to study researcher Naoto Takahashi, MD, of Akita University Graduate School of Medicine, Akita City, Japan, these results could affect clinical practice.
“In this study, imatinib was switched to nilotinib for 2-year consolidations,” Dr Takahashi said. “That is a unique strategy for achieving successful treatment-free remission. It suggests that 2-year consolidation by nilotinib should be more effective than that by imatinib in the STIM1 study.”
Nilotinib is a second-generation TKI that is highly effective for patients with Philadelphia chromosome-positive CML in chronic phase. However, recently, treatment-free remission has been suggested as an ultimate goal for CML treatment.
“Patients want to stop TKIs for a variety of reasons,” Dr Takahashi revealed to Cancer Therapy Advisor.
In a previous study, Dr Takashashi and colleagues looked at the possibility of discontinuation of imatinib in Japanese patients with CML who experienced complete molecular response.3In the small retrospective study, a variety of reasons were listed for wanting to discontinue TKI therapy including adverse events, cost, a desire to become pregnant, and long undetectable residual disease.