Early results on remission rates after discontinuation of nilotinib

This study examined outcomes after discontinuation of nilotinib (Tasigna) in patients with chronic myeloid leukemia (CML). Researchers reported that over half of CML patients were able to sustain a deep treatment response for at least 48 weeks after stopping nilotinib.

Major molecular response (MMR) is a response to treatment where hardly any genetic abnormalities can be found in the bone marrow. Treatment-free remission (sustained MMR) or deep molecular response (showing no more genetic abnormalities in the bone marrow) is often considered the main goal of CML treatment.

Many patients achieve this treatment goal with tyrosine kinase inhibitor (TKI) therapy, such as nilotinib. TKIs are a type of targeted therapy that block enzymes called tyrosine kinases. However, CML patients are generally expected to continue TKI treatment throughout their lives. Many patients lose their treatment response once TKI therapy is stopped. More studies are needed to better understand outcomes after discontinuation of nilotinib.

The aim of this study was to evaluate remission rates after discontinuation of nilotinib.

215 CML patients were included. All patients were positive for the Philadelphia chromosome (a genetic abnormality making CML more difficult to treat). Patients were treated with nilotinib for 2 years or more and showed deep molecular response for at least 1 year. Patients were followed for at least 48 weeks after stopping nilotinib.

190 patients (88.4%) showed sustained MMR after stopping nilotinib and were therefore considered to be in treatment-free remission. The average length of nilotinib treatment before treatment-free remission was 43.5 months.

At 48 weeks, 98 patients (51.6%) remained in treatment-free remission. 86 patients lost MMR and restarted treatment. Of these, 98.8% regained MMR and 88.4% regained deep molecular response.

65.8% of patients reported side effects during the first 48 weeks of treatment-free remission. Common side effects included muscle pain, the common cold and joint pain.

This study concluded that over half of CML patients were able to remain in MMR for at least 48 weeks after stopping nilotinib. Authors advised that further follow-up studies are needed.

Further studies are needed to confirm these preliminary results.