Real-world treatment adherence and persistence of FLT3 inhibitors as post-alloHCT maintenance therapy in patients with AML in the United States: a cohort study using administrative claims data

In <i>FLT3-</i>mutated (<i>FLT3</i>^mut+) acute myeloid leukemia (AML), relapse after allogeneic hematopoietic cell transplantation (alloHCT) is the leading cause of treatment failure and mortality. We evaluated real-world adherence and persistence of FLT3-like-tyrosine kinase inhibitors as alloHCT maintenance in <i>FLT3</i>^mut+ AML. Claims data were extracted from adults with AML with ≥1 alloHCT between January 2016 and June 2022 who received gilteritinib, midostaurin, or sorafenib as post-alloHCT maintenance. Adherence (PDC; days covered ≥80% during follow-up) and persistence (days receiving treatment without switch/gap >60 days) were assessed. Of 162 patients, 41, 53, and 68 received post-alloHCT gilteritinib, midostaurin, or sorafenib, respectively. Adherence was higher in patients with a history of relapsed/refractory disease before alloHCT (<i>n</i> = 106 [65.4%], <i>p</i> = .021). Although this study did not focus on outcomes, no significant differences in post-alloHCT relapse by PDC were found. Discontinuation risk was higher for midostaurin (HR = 2.79, <i>p</i> = .0005) and sorafenib (HR = 1.74, <i>p</i> = .046) versus gilteritinib in patients with Commercial insurance vs Medicare/Medicaid (HR = 1.68, <i>p =</i> .019).