AUGMENT-101: This phase I/II study is assessing the best dose level, safety and effectiveness of a new drug (SNDX-5613) in people with acute leukaemiaA Phase 1/2, Open-label, Dose-Escalation and Dose-Expansion Cohort Study of SNDX-5613 in Patients With Relapsed/Refractory Leukemias, Including Those Harboring an MLL/KMT2A Gene Rearrangement or Nucleophosmin 1 (NPM1) Mutation

Inclusion

Participants must have active acute leukemia (bone marrow blasts ≥5% or reappearance of blasts in peripheral blood) as defined by the National Comprehensive Cancer Network (NCCN) in the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) for Acute Lymphoblastic Leukemia (Version 1.2020) and Acute Myeloid Leukemia (Version 3.2020), or acute leukemia harboring an MLL rearrangement, NUP98 rearrangement, or NPM1c mutation that have detectable disease in the bone marrow.

1. Phase 1:

   • Arm A: Participants not receiving any strong CYP3A4 inhibitor/inducers or fluconazole.
   • Arm B: Participants receiving itraconazole, ketoconazole, posaconazole, or voriconazole (strong CYP3A4 inhibitors) for antifungal prophylaxis.
   • Arm C: Participants receiving SNDX-5613 in combination with cobicistat.
   • Arm D: Participants receiving fluconazole (moderate CYP3A4 inhibitor).
   • Arm E: Participants not receiving any weak, moderate, or strong CYP3A4 inhibitors/inducers.
   • Arm F: Participants receiving isavuconazole (moderate CYP3A4 inhibitor) for antifungal prophylaxis.

2. Phase 2:

   • Cohort 2A: Documented R/R ALL/MPAL with an MLLr translocation.
   • Cohort 2B: Documented R/R AML with an MLLr translocation.
   • Cohort 2C: Documented R/R AML with NPM1c.
3. White blood cell count below 25,000/ microliter at time of enrollment. Participants may receive cytoreduction prior to enrollment per protocol-specified criteria.
4. Male or female participants aged ≥30 days old.
5. Eastern Cooperative Oncology Group (ECOG) performance status score 0-2 or Karnofsky/Lansky score ≥50.
6. Any prior treatment-related toxicities resolved to ≤Grade 1 prior to enrollment, with the exception of ≤Grade 2 neuropathy or alopecia.
7. Radiation Therapy: At least 60 days from prior total body irradiation (TBI), craniospinal radiation and/or ≥50% radiation of the pelvis, or at least 14 days from local palliative radiation therapy (small port).
8. Stem Cell Infusion: At least 60 days must have elapsed from hematopoietic stem cell transplant and at least 4 weeks must have elapsed from donor lymphocyte infusion.
9. Immunotherapy: At least 42 days since prior immunotherapy, including tumor vaccines and checkpoint inhibitors, and at least 21 days since receipt of chimeric antigen receptor therapy or other modified T cell therapy.
10. Antileukemia Therapy: At least 14 days, or 5 half-lives, whichever is shorter, since the completion of antileukemic therapy.
11. Hematopoietic Growth Factors: At least 7 days since the completion of therapy with short-acting hematopoietic growth factors and 14 days with long-acting growth factors.
12. Biologics: At least 90 days, or 5 half-lives, whichever is shorter, since the completion of therapy with an antineoplastic biologic agent.
13. Steroids: At least 7 days since systemic glucocorticoid therapy, unless receiving physiologic dosing (equivalent to ≤10 mg prednisone daily) or cytoreductive therapy.
14. Adequate organ function.
15. If of childbearing potential, willing to use a highly effective method of contraception or double barrier method from the time of enrollment through 120 days following the last study drug dose.