Evaluating long-term outcomes after low dose pegylated interferon-α combined with dasatinib in patients with chronic phase chronic myeloid leukemia

This study aimed to investigate the long-term safety and effectiveness of low-dose pegylated (PEG) interferon-α (IFN-α) combined with dasatinib in patients with chronic-phase (CP) chronic myeloid leukemia (CML). 

This study concluded that this treatment was safe and effective in the long-term in these patients.  

Treatment free remission (TFR) is now a goal in CP-CML. Combinations of tyrosine kinase inhibitors (TKIs) such as dasatinib (Sprycel) and other drugs are used to attempt to increase the number of patients achieving TFR.  

PEG-IFN-α (Pegasys) is an immunotherapy which when combined with a TKI has shown good effectiveness. However, in higher doses, it can cause side effects that lead to patients stopping treatment. However, whether adding PEG-IFNα in low-dose to dasatinib treatment is safe and effective in the long-term in patients with CP-CML is still unknown. 

This study involved 40 patients with newly diagnosed CP-CML who were treated with dasatinib (DAS). After 3 months, PEG-IFN-α was added to the treatment and was increased each week from months 7 to 15 up to 25 µg/week. Patients were followed up for 5 years. 

After 5 years, there were no suspected unexpected serious side effects. There were also no disease progression during 5 years. 

At month 60, the major molecular response (MMR) rate was 84.6%. 95% of patients reached MMR at some point during the study. MMR is a very low level (0.001% or less) of the BCR-ABL gene involved in CML.

This study concluded that the initial addition of low-dose PEG-IFN-α to dasatinib shows good long-term effectiveness and safety without increased toxicity in patients with CP-CML. 

This study included a very low number of patients. Also, after 2 years, follow-up was done every year, which may have reduced the reported side-effects.