A Study of ASP2215 Versus Salvage Chemotherapy in Patients With Relapsed or Refractory Acute Myeloid Leukemia (AML) With FMS-like Tyrosine Kinase (FLT3) Mutation

Inclusion Criteria

• Participant has a diagnosis of primary acute myeloid leukemia (AML) or AML secondary to myelodysplastic syndrome (MDS) according to WHO classification (2008) as determined by pathology review at the treating institute.
• Participant is refractory to or relapsed after first-line AML therapy (with or without hematopoietic stem cell transplant (HSCT)).
• Refractory to first-line AML therapy is defined as:
• Participant did not achieve complete remission/complete remission with incomplete hematologic recovery/complete remission with incomplete platelet recovery (CR/CRi/CRp) under initial therapy. A Participant eligible for standard therapy must receive at least one cycle of an anthracycline containing induction block in standard dose for the selected induction regimen. A Participant not eligible for standard therapy must have received at least one complete block of induction therapy seen as the optimum choice of therapy to induce remission for this subject.
• Untreated first hematologic relapse is defined as:
• Participant must have achieved a CR/CRi/CRp (criteria as defined by [Cheson et al, 2003], see Section 5.3) with first line treatment and has hematologic relapse.
• Participant is positive for FLT3 mutation in bone marrow or whole blood as determined by the central lab. A Participant with rapidly proliferative disease and unable to wait for the central lab results can be enrolled based on a local test performed after completion of the last interventional treatment. Participants can be enrolled from a local test result if they have any of the following FLT3 mutations: FLT3 internal tandem duplication (ITD), FLT3 tyrosine kinase domain (TKD)/D835 or FLT3- TKD/I836.
• Participant has an Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2.
• Participant is eligible for pre-selected salvage chemotherapy.
• Participant must meet the following criteria as indicated on the clinical laboratory tests:
• Serum aspartate aminotransferase and alanine aminotransferase ≤ 2.5 x upper limit of normal (ULN)
• Serum total bilirubin ≤ 1.5 x ULN
• Serum creatinine ≤ 1.5 x ULN or an estimated glomerular filtration rate of > 50 mL/min as calculated by the Modification of Diet in Renal Disease equation.
• Participant is suitable for oral administration of study drug.
• Female Participant must either:
• Be of non-child bearing potential:
• post-menopausal (defined as at least 1 year without any menses) prior to Screening, or
• documented as surgically sterile (at least 1 month prior to Screening)
• Or, if of childbearing potential,
• Agree not to try to become pregnant during the study and for 180 days after the final study administration
• And have a negative urine pregnancy test at Screening
• And, if heterosexually active, agree to consistently use highly effective contraception per locally accepted standards in addition to a barrier method starting at Screening and throughout the study period and for 180 days after the final study drug administration.
• Female Participant must agree not to breastfeed at Screening and throughout the study period and for 60 days after the final study drug administration.
• Female Participant must not donate ova starting at Screening and throughout the study period and for 180 days after the final study drug administration.
• Male Participant and their female partners who are of childbearing potential must be using highly effective contraception per locally accepted standards in addition to a barrier method starting at Screening and continue throughout the study period and for 120 days after the final study drug administration.
• Male Participant must not donate sperm starting at Screening and throughout the study period and 120 days after the final study drug administration.
• Participant agrees not to participate in another interventional study while on treatment.

Exclusion Criteria

• Participant was diagnosed as acute promyelocytic leukemia (APL).
• Participan