The following criteria is provided for health care professionals.

Inclusion Criteria

• First allogeneic HSCT, in ≤ CR2, and MRD negative prior to transplant (including matched sibling, MUD with at least 6 of 8 HLA markers, or haploidentical with at least 5 of 10 HLA markers) as:
  • Adjuvant therapy for AML (Group 1) at 90 days (±10 days) post-HSCT defined as patients with CRMRD; or
  • Treatment for refractory/relapsed AML (first relapse post-HSCT) when disease occurs after transplant (Group 2) defined as
    • First relapse (MRD+ or frank relapse) post-HSCT
    • Patients in Arm 1B (SOC) who experience first relapse (MRD+ or frank relapse) post HSCT
  • Safety Lead-in defined as patients who fit all the criteria for Group 2 only
• Are ≥18 years of age
• Karnofsky/Lansky score of ≥60
• Life expectancy ≥12 weeks
• Adequate blood, liver, and renal function
  • Blood: Hemoglobin ≥7.0 g/dL (can be transfused)
  • Liver: Bilirubin ≤2X upper limit of normal; aspartate aminotransferase ≤3X upper limit of normal
  • Renal: Serum creatinine ≤2X upper limit of normal or measured or calculated creatinine clearance ≥45mL/min
• Patients are allowed to be on experimental conditioning regimens prior to transplant if no planned maintenance therapy post-transplant.
• In Group 2, patients may receive bridging therapy at the investigators' discretion in situations where MT-401 is not ready for administration or the treating physician believes the patient would benefit

Exclusion Criteria

• Clinically significant or severely symptomatic intercurrent infection
• Pregnant or lactating
• For Group 1, anti-neoplastic therapy after HSCT and prior to or during dosing of MT-401
• For Group 2, concomitant anti-neoplastic therapy during or after dosing of MT-401
• Evidence of acute or chronic GVHD ≥Grade 2 (exception: acute or chronic Grade 2 GVHD of skin allowed if stable) within one week prior to receiving MT-401