What is the recommended management for acute myeloid leukemia?

Management of Acute Myeloid Leukemia

Treatment for AML must be stratified based on patient fitness for intensive chemotherapy and molecular/cytogenetic risk profile, with younger fit patients receiving intensive induction chemotherapy (typically "7+3" with targeted agents when indicated) followed by consolidation with high-dose cytarabine or allogeneic hematopoietic cell transplantation, while older or unfit patients receive hypomethylating agents combined with venetoclax. 1, 2

Initial Risk Stratification

Before selecting therapy, perform comprehensive molecular and cytogenetic testing to determine ELN risk classification 2. Critical molecular markers include:

• FLT3-ITD and FLT3-TKD mutations (allelic ratio ≥0.05)
• NPM1 mutations
• IDH1 and IDH2 mutations
• TP53 mutations
• KMT2A rearrangements
• Core binding factor abnormalities (RUNX1-RUNX1T1, CBFB-MYH11)
• CD33 expression status

Assess patient fitness using age, performance status, and comorbidity indices (HCT-CI score) 1.

Treatment Algorithm for Fit Patients (Intensive Chemotherapy Candidates)

Induction Therapy

For therapy-related AML (tAML) or AML with myelodysplasia-related changes (MRC-AML) in patients ≥60 years:

• CPX-351 (liposomal daunorubicin/cytarabine) is the preferred regimen 1. This improved 2-year overall survival by 18.8% to 31.1% compared to standard 7+3 in this population. CPX-351 is also recommended for FLT3-mutated tAML or MRC-AML, as it showed superior efficacy (median OS 10.25 vs 4.6 months) 1.

For core binding factor AML (CBF-AML) with CD33-positive blasts:

• 7+3 plus gemtuzumab ozogamicin (GO) 1. The meta-analysis showed GO improved 6-year overall survival by 20.7% to 75.5% in CBF-AML 1. GO can be given as a single 3 mg/m² dose on day 1 or fractionated on days 1,4, and 7. Critical caveat: Allow at least 2 months between last GO dose and allogeneic transplant conditioning to reduce risk of hepatic sinusoidal obstruction syndrome 1.

For FLT3-ITD or FLT3-TKD positive AML (excluding tAML/MRC-AML):

• 7+3 plus midostaurin 1, 3. Midostaurin improved 4-year OS by 7.1% to 51.4% in the RATIFY trial 1. Continue midostaurin through consolidation but do not use as maintenance after consolidation or after allogeneic transplant 1.

For all other AML:

• Standard 7+3 (cytarabine 100-200 mg/m² continuous infusion days 1-7 plus daunorubicin 60-90 mg/m² or idarubicin days 1-3) 1, 2. Consider adding GO in younger CD33-positive patients with ELN favorable or intermediate risk (improved 6-year OS by 5.7% in intermediate-risk cytogenetics) 1. Do not add GO in adverse-risk cytogenetics—no survival benefit 1.

Consolidation Therapy

For CBF-AML:

• High-dose cytarabine (HiDAC) 3 g/m² every 12 hours on days 1,3,5 for 3-4 cycles 1. Add GO in cycles 1 and 2 if CD33-positive and age <60-65 years 1. Allogeneic transplant is generally not indicated in first complete remission for CBF-AML unless high-risk features present 1.

For ELN intermediate-risk AML:

• Allogeneic hematopoietic cell transplantation (alloHCT) in first complete remission 1. If transplant not feasible, give HiDAC or consider autologous transplant 1.

For ELN adverse-risk AML:

• Allogeneic transplant in first complete remission is mandatory 1, 2. This is the only potentially curative option for this group.

For FLT3-mutated AML:

• Continue midostaurin through consolidation if used in induction 1. Proceed to allogeneic transplant for all except possibly favorable-risk disease 3.

Transplant Considerations

Donor selection priority 1:

1. HLA-identical sibling or 10/10 or 9/10 matched unrelated donor (if search time <3 months)
2. Umbilical cord blood or haploidentical donor (depending on center experience and patient age)

Conditioning regimen selection 1:

• Myeloablative conditioning (MAC) for patients ≤55 years with HCT-CI <2 (fludarabine/busulfan preferred over busulfan/cyclophosphamide due to less toxicity)
• Reduced-intensity conditioning (RIC) for all other patients
• Use TBI-based conditioning only for CNS disease or myeloid sarcoma 1

Treatment Algorithm for Unfit Patients (Not Intensive Chemotherapy Candidates)

For patients unable to tolerate intensive chemotherapy due to age (typically >75 years), poor performance status, or significant comorbidities:

First-Line Therapy

Hypomethylating agent (HMA) plus venetoclax is the standard of care 1, 3, 4:

• Azacitidine 75 mg/m² days 1-7 or decitabine 20 mg/m² days 1-5 plus venetoclax (ramp-up dosing: 100 mg day 1,200 mg day 2,400 mg day 3 onwards for 28 days of each cycle)
• This combination has revolutionized therapy for older adults with AML 5

Add targeted agents when molecular markers present:

For FLT3-mutated AML:

• Consider adding FLT3 inhibitor to HMA-venetoclax, though data are still emerging 3, 4

For IDH1-mutated AML:

• Ivosidenib or olutasidenib can be used as monotherapy or potentially combined with HMA-venetoclax 5, 6, 4

For IDH2-mutated AML:

• Enasidenib can be used as monotherapy or potentially combined with HMA-venetoclax 5, 6, 4

Important consideration: While IDH inhibitors are available, venetoclax-based regimens have shown particular efficacy in IDH-mutated populations, raising questions about optimal sequencing 6.

Post-Remission Therapy

Duration of HMA-venetoclax: Continue until disease progression, unacceptable toxicity, or proceeding to allogeneic transplant 3. Selected patients achieving complete remission may be candidates for allogeneic transplant with RIC 1.

Maintenance therapy:

• Oral azacitidine (CC-486) for patients ≥55 years who achieved CR after intensive chemotherapy showed improved survival in recent trials, though not yet universally approved 1, 4
• Do not use midostaurin maintenance after consolidation—exploratory analysis failed to show benefit 1

Relapsed/Refractory Disease

For FLT3-mutated relapsed/refractory AML:

• Gilteritinib 120 mg daily is preferred 5, 7, 4. Showed superior survival compared to salvage chemotherapy. Proceed to allogeneic transplant if response achieved.
• Quizartinib is an alternative FLT3 inhibitor 5, 4

For IDH1-mutated relapsed/refractory AML:

• Ivosidenib or olutasidenib 5, 6, 4

For IDH2-mutated relapsed/refractory AML:

• Enasidenib 5, 6

For NPM1-mutated or KMT2A-rearranged relapsed/refractory AML:

• Revumenib (menin inhibitor) was approved in November 2024 and shows significant activity in this population 6, 4. This represents a major advance for these molecular subsets.

For patients without targetable mutations:

• Chemotherapy-based re-induction followed by allogeneic transplant if response achieved 7
• Clinical trial enrollment strongly encouraged

Special Populations

TP53-Mutated AML

This remains the most challenging subgroup with dismal prognosis 6, 4. HMA-venetoclax produces initial responses but remissions are short-lived with poor overall survival 6. Proceed directly to allogeneic transplant if any response achieved, though long-term outcomes remain poor. Enroll in clinical trials whenever possible 6.

Acute Promyelocytic Leukemia (APL)

Refer to separate APL-specific guidelines—this is a distinct entity requiring all-trans retinoic acid (ATRA) and arsenic trioxide-based therapy 8.

Critical Pitfalls to Avoid

1. Do not delay molecular testing—results directly impact initial therapy selection 2
2. Do not use GO in adverse-risk cytogenetics outside CBF-AML—no benefit and increased toxicity 1
3. Do not delay allogeneic transplant for eligible patients with intermediate or adverse-risk disease 1
4. Do not use midostaurin maintenance after consolidation or transplant—no proven benefit 1
5. Allow adequate time (≥2 months) between GO and transplant conditioning to reduce hepatic toxicity risk 1
6. Do not use CPX-351 in patients previously treated with HMAs for MDS—no benefit shown in this subgroup 1