About one-third of all acute myeloid leukemia (AML) patients carry a genetic mutation for which doctors had no targeted treatment for decades. That has changed: two newly approved menin inhibitors are the first therapies to specifically target NPM1 mutations and KMT2A rearrangements. In clinical trials, one-quarter of seriously ill patients achieved complete remission. For a disease with a median survival of six to eight months upon relapse, this is a significant step forward.
What is AML and why is the NPM1 mutation so central?
Acute myeloid leukemia is the most common form of acute leukemia in adults. About 4,300 people are diagnosed annually in Germany. The disease occurs when immature white blood cells grow uncontrollably and crowd out normal blood cell production. Without treatment, it is fatal within weeks.
The main challenge has been a specific genetic alteration: mutation of the NPM1 gene (nucleophosmin 1). According to data from the journal Blood, it occurs in 27 to 35 percent of all AML cases, and in patients with normal chromosomes, in 45 to 60 percent. Although NPM1-mutated AML initially often responds well to chemotherapy, the disease returns in many patients. Upon relapse without additional targeted options, median survival was six to eight months, with five-year survival rates below twenty percent.
A second target structure is KMT2A rearrangement (formerly MLL translocation), which occurs in three to seven percent of adult AML cases and in up to 25 percent of pediatric cases.
How menin inhibitors intervene in tumor mechanisms
The protein menin normally forms a complex with the KMT2A protein. In AML cells with KMT2A rearrangements or NPM1 mutations, this complex drives uncontrolled activation, keeping leukemia cells in an immature, highly proliferative state. Menin inhibitors block precisely this protein-protein interaction.
The U.S. Food and Drug Administration has approved two such inhibitors. Revumenib (trade name REVUFORJ, Syndax Pharmaceuticals) received its first approval in November 2024 for patients with KMT2A rearrangements and an expanded approval in October 2025 for NPM1-mutated AML. Ziftomenib (KOMZIFTI, Kura Oncology and Kyowa Kirin) followed in November 2025 as the second menin inhibitor, approved for relapsed or refractory NPM1-mutated AML. It is the first menin inhibitor without cardiac warnings in the package insert and can be taken orally once daily.
What the study data shows
In the AUGMENT-101 trial with revumenib, 23.4 percent of evaluable NPM1 patients achieved complete remission or complete remission with partial hematologic recovery (CR/CRh). In the KMT2A cohort, this rate was 23 percent, with overall response rates of 63 percent. Notably, according to findings in Blood, 64 percent of patients in remission showed no measurable leukemia cells (MRD negativity). These patients are candidates for subsequent stem cell transplantation, which could enable permanent cure.
In the KOMET-001 trial with ziftomenib, the CR/CRh rate was 22 percent (Phase 2 cohort, n=92), with MRD negativity in 61 percent. Three percent of patients discontinued treatment due to drug-related side effects, low for this heavily pretreated population. Memorial Sloan Kettering Cancer Center called this drug class one of the most promising approaches for one of the hardest-to-treat leukemias.
Oncologists note critically that remission in one-quarter of patients is a meaningful result for this population but does not mean cure. For patients ineligible for stem cell transplantation, prognosis remains limited. Early clinical data also describe resistance mechanisms where tumor cells develop new mutations under menin inhibitor therapy.
In comparison: how AML developed a differentiated treatment landscape
Until 2017, chemotherapy was the only standard option for nearly all AML patients, regardless of genetic makeup. Since then, the FDA has approved more than ten new drugs for AML. FLT3 inhibitors like midostaurin (approved 2017) first opened targeted therapy for FLT3-mutated patients. IDH1 and IDH2 inhibitors (ivosidenib, approved 2018; enasidenib, approved 2017) enabled targeted treatment for IDH-mutated patients.
Menin inhibitors now close the gap for NPM1 and KMT2A patients. This means a large portion of the AML population now has at least one targeted option instead of universal chemotherapy. In 2010, AML had few options beyond chemotherapy and stem cell transplantation. In less than 15 years, the treatment landscape has transformed fundamentally.
Three conditions for menin inhibitors to become the AML standard
For these drugs to move from second-line to first-line treatment, three conditions must be met.
First, ongoing trials must confirm efficacy in the first-line setting. Current approvals apply only to relapsed or refractory patients. Several ongoing clinical trials are now testing menin inhibitors combined with intensive or low-dose chemotherapy in newly diagnosed AML.
Second, the breadth of use depends on access. Both drugs come from specialized pharmaceutical companies. This means reimbursement decisions and insurance negotiations will determine whether patients outside major research centers gain access.
Third, managing resistance will be central. Combination strategies with venetoclax, azacitidine, and other drugs are currently under investigation. For researchers at Dana-Farber Cancer Institute, whose work contributed to revumenib's NPM1 approval, this is the critical next phase: not whether menin inhibitors work, but how long they work and how to extend their efficacy.