Patient-Tailored Gilteritinib Triplet Therapy Shows Tolerability Gains in Relapsed FLT3-Mutated AML

A multicenter retrospective study from Sweden suggests that adjusting how the three-drug combination of azacitidine, venetoclax and gilteritinib is scheduled can reduce myelosuppression and infectious complications in patients with FLT3-mutated relapsed or refractory acute myeloid leukemia, while apparently preserving the encouraging response rates and survival outcomes reported for full concomitant triplet therapy. The findings were published open access in Annals of Hematology on 23 October 2026.

FLT3-mutated acute myeloid leukemia is associated with high relapse rates and treatment resistance, making it one of the more difficult molecular subtypes to manage once the disease has returned or failed to respond to initial therapy. Triplet therapy combining the hypomethylating agent azacitidine, the BCL2 inhibitor venetoclax and the FLT3 inhibitor gilteritinib has previously yielded high response rates in this setting, but its use has been limited by myelosuppression and infections, the study authors note.

The research team analyzed 29 patients with FLT3-mutated AML who were treated with gilteritinib-based triplets across multiple centers. The primary endpoint of the study was overall survival, with event-free survival and the time to neutrophil and platelet recovery serving as secondary endpoints. Patients had received one of three different regimens, reflecting a deliberate evolution in how the drugs were combined over time.

Patients in the first group received fully concomitant triplet therapy, with all three drugs given together. Those in the second group received concomitant azacitidine and venetoclax followed by concomitant venetoclax and gilteritinib, staggering the FLT3 inhibitor relative to the start of the backbone pair. Patients in the third group received overlapping azacitidine and venetoclax followed by gilteritinib as monotherapy, meaning the three drugs were never combined at the same time in that schedule.

For the entire cohort, median overall survival was not reached after more than five years of follow-up, a striking result in a relapsed or refractory population where median survival is typically measured in months. High response rates were observed across all three schedules, indicating that no single way of sequencing the drugs appeared to sacrifice antileukemic activity.

The tolerability signal emerged when the researchers compared the schedules with one another. Limiting the period of concomitant exposure to all three drugs reduced myelosuppression and decreased infectious complications compared with full triplet therapy. Because myelosuppression and infections are the principal reasons clinicians shorten or discontinue otherwise effective combinations, this observation carries practical weight for how such regimens might be delivered.

Survival outcomes differed across the groups in ways the authors describe as encouraging for the schedules with greater drug overlap. Median overall survival was not reached in the first and second groups after three years of follow-up, whereas the third group, in which gilteritinib was given only as monotherapy after the azacitidine-venetoclax phase, had a median overall survival of 18 months. Event-free survival followed a similar pattern: median event-free survival was 40.5 months in the first group and was not reached at five years in the second group, compared with 11.5 months in the third group.

Taken together, the data suggest that the second schedule, in which azacitidine and venetoclax are started together and venetoclax is then paired with gilteritinib, may offer a middle path: enough concurrent exposure to preserve efficacy, but less sustained triple-drug overlap than the fully concomitant approach. The authors conclude that reducing the duration of triple-drug overlap may improve tolerability without compromising clinical outcomes.

As a retrospective study of 29 patients, the analysis cannot establish causality between scheduling and outcomes, and the group comparisons are subject to the biases inherent in non-randomized, single-arm observations. Even so, the findings provide a real-world benchmark for how gilteritinib triplets are being delivered outside trial settings and identify the duration of triple-drug overlap as a variable that clinicians and trial designers can manipulate in pursuit of a better balance between efficacy and toxicity in FLT3-mutated relapsed or refractory AML.

Subject of Research: Patient-tailored azacitidine, venetoclax and gilteritinib triplet scheduling in FLT3-mutated relapsed/refractory acute myeloid leukemia

Article Title: Patient-tailored azacitidine, venetoclax and gilteritinib triplet therapy appear to improve tolerability while preserving encouraging clinical outcomes in FLT3-mutated relapsed/refractory AML

Article References: Arvidsson Kvissberg, M., Nilsson, C., Landberg, N., Österroos, A., Papageorgiou, A., Uggla, B., Lazarevic, V., Deneberg, S., & Jädersten, M. (2026). Patient-tailored azacitidine, venetoclax and gilteritinib triplet therapy appear to improve tolerability while preserving encouraging clinical outcomes in FLT3-mutated relapsed/refractory AML. Annals of Hematology, 105(11), Article 479. https://doi.org/10.1007/s00277-026-07297-2

Image Credits: AI Generated

DOI: 10.1007/s00277-026-07297-2

Keywords: AML, FLT3 mutation, gilteritinib, venetoclax, azacitidine, triplet therapy, relapsed refractory leukemia, myelosuppression, overall survival, retrospective study, Patient-tailored, triplet