TP-0903 Shows Early Signs of Activity in Heavily Pretreated FLT3-ITD AML Patients

In a phase 1b/2 trial, three relapsed/refractory AML patients with FLT3-ITD mutations were treated with oral TP-0903, starting at 50 mg daily—with dose reduction to 37 mg for one patient due to manageable grade 3 nausea. All patients achieved stable disease, and two exhibited significant reductions in bone marrow blast percentages that correlated with decreased FLT3-ITD allelic ratios and lower variant allele frequencies of co-occurring mutations (e.g., NPM1, DNMT3A), highlighting the drug's multi-kinase inhibitory action against key resistance pathways.

The encouraging early clinical activity and favorable tolerability profile of TP-0903 in a difficult-to-treat AML population support further investigation to solidify its role in overcoming FLT3 inhibitor resistance.