Pilot study: A prospective, real-world, feasibility study testing a decreased frequency paradigm in treatment free remission in chronic myeloid leukemia.

Treatment Free Remission (TFR) is an established goal for patients with the diagnosis of chronic myeloid leukemia (CML). The purpose of this prospective feasibility pilot study was assessing a new, real-world paradigm for safely stopping TKI treatment by monitoring molecular response through PCR tests determining BCR::ABL levels every 6 weeks instead of the recommended 4-week intervals. A successful re-establishment of MMR after loss of TFR was the primary endpoint. Eligibility criteria for this study included maintaining major molecular response 4 log reduction (MMR4) for 2 years and a total of TKI therapy for 5 years. The primary endpoint was successful maintenance of ≥ MMR at 6 months. 18 patients were enrolled, 13 of the 18 participants maintained TFR, and all 5 patients regained MMR with resumption of TKI treatment. We demonstrated that this pilot study was feasible in a community setting using 6-week intervals. This study will be expanded to other sites using a 6-week testing interval.