A Phase 1/2, First in Human, Dose Escalation Study of MGD006, a CD123 x CD3 DART® Bi-Specific Antibody Based Molecule, in Patients With Relapsed or Refractory AML or Intermediate-2/High Risk Myelodysplastic Syndrome (MDS)
Open-label, multi-dose, single-arm, multi-center, Phase 1/2 study conducted in three segments: the Single Patient Dose Escalation Segment (complete), followed by the Multi-Patient Dose Escalation Segment (complete) and the Maximum Tolerated Dose and Schedule (MTDS) Expansion Cohort Segment (closed). Having characterized safety and determined the maximum tolerated dose and schedule, the primary objective of this study now is to assess the anti-neoplastic activity of flotetuzumab in patients with PIF/ER AML, as determined by the proportion of patients who achieve CR or CRh. Starting with Cycle 2, patients who are benefiting from flotetuzumab may receive up to a maximum of 8 cycles of treatment. Patients will receive daily increasing doses of flotetuzumab for the first week of Cycle 1 (Lead-In Dosing) followed by 3 weeks of continuous intravenous infusion at a the assigned dose. Subsequent cycles are each 4 weeks of continuous infusion at the assigned dose. Dosing may continue for up to 8 cycles. Follow up visits may continue for 6 months after treatment is discontinued.
• Confirmed diagnosis of primary or secondary AML \[any subtype except acute promyelocytic leukemia (APL)\] according to World Health Organization (WHO) classification
• Patients with AML must meet one of the following criteria, a or b:
‣ Primary Induction Failure (PIF) AML, defined as disease refractory to either, i or ii:
• i. An intensive induction attempt, per institution. Induction attempts include high-dose and/or standard-dose cytarabine ± an anthracyclines/anthracenedione ± an anti-metabolite, with or without growth factor or targeted therapy containing regimens. Examples include but are not limited to: 1 cycle of high dose cytarabine (HiDAC) containing regimen, 1 cycle of liposomal cytarabine and daunorubicin, 2 cycles of standard dose cytarabine containing regimen
∙ ii. For adults who are age 75 years or older, or who have comorbidities that preclude use of intensive induction chemotherapy; PIF is defined as AML refractory to one of the following less intensive regimens: i ≥ 2 but ≤ 4 cycles of Bcl-2 inhibitors in combination with azacitidine, decitabine, or low dose cytarabine, or ii ≥ 2 but ≤ 4 cycles of gemtuzumab ozogamicin monotherapy
⁃ Early relapse (ER) AML, defined as AML in first relapse with initial CR1 duration \< 6 months
• Limit of 3 prior lines of therapy (excluding focal radiation therapy for palliative purposes): up to 2 induction (induction, re-induction) or 1 induction plus/minus 1 consolidation attempt, followed by a maximum of 1 salvage/re-induction attempt.
• Eastern Cooperative Oncology Group (ECOG) performance status ≤2
• Life expectancy of at least 4 weeks
• Peripheral blast count \</= 20,000/mm3 at the time of first dose
• Acceptable laboratory parameters and adequate organ reserve