A Study of Anti-Cancer Therapies Targeting the MAPK Pathway in Patients With Hematologic Malignancies

Inclusion Criteria: * Age ≥ 18 years. * Willing and able to give written informed consent. * Diagnosis of primary AML or AML secondary to myelodysplastic syndrome (MDS) according to World Health Organization classification. * Relapsed after or refractory to first-line AML therapy. * Positive for FLT3 mutation in bone marrow or whole blood. * Eastern Cooperative Oncology Group performance status ≤ 2 with no deterioration during screening period. * Adequate hepatic and renal function. * Recovery from non-hematologic AEs associated with prior therapy to baseline CTCAE v5 Grade 0 or 1, except for AEs not considered a safety risk (eg, alopecia or vitiligo). * Able to take oral medication with no medical conditions that prevent swallowing and absorbing oral medications. * Willing to comply with all protocol-required visits, assessments, and procedures. Exclusion Criteria: * Diagnosis of AML secondary to prior chemotherapy or other neoplasms (except for MDS). * Diagnosis of acute promyelocytic leukemia or BCR-ABL-positive leukemia (chronic myeologenous leukemia in blast crisis). * Clinically active central nervous system leukemia. * Second or later hematologic relapse or prior salvage therapy for refractory disease. * For participants being considered for ERAS-007+gilteritinib treatment: prior therapy with ERK inhibitor. * For participants being considered for ERAS-601+gilteritinib treatment: prior therapy with SHP2 inhibitor. * Anticancer therapy ≤14 days prior to first dose (except hydroxyurea given for controlling blast count), or ≤5 half-lives prior to first dose, whichever is shorter. * Palliative radiation ≤7 days prior to first dose. * Major surgery within 28 days of enrollment. * Contraindication to gilteritinib use as per local label. * Known hypersensitivity to any of the components of ERAS-007 or ERAS-601. * Clinically active infection, requiring systemic therapy. * Impaired cardiovascular function or clinically significant cardiovascular disease. * History of thromboembolic or cerebrovascular events ≤6 months prior to first dose. * History of other malignancy ≤3 years prior to first dose. * History of retinal pigment epithelial detachment (RPED), central serous retinopathy, retinal vein occlusion (RVO), or risk factors to RPED or RVO. * History of or clinically active interstitial lung disease (ILD), drug induced ILD, or radiation pneumonitis that required steroid treatment. * Any evidence of severe or uncontrolled systemic disease or evidence of any other significant clinical disorder or laboratory finding that renders the participant inappropriate to participate in the study. * Pregnant or breastfeeding women.