Trial results for the BLAST MRD AML-1 study (NCT04214249) investigating pembrolizumab in combination with intensive chemotherapy for acute myeloid leukemia were posted on ClinicalTrials.gov on 2026-03-04. The Phase 2 study found no statistically significant difference in minimal residual disease (MRD) negativity or complete response rates between the pembrolizumab arm and the standard therapy arm.
Background
Pembrolizumab (Keytruda) is an immunotherapy drug. The BLAST MRD AML-1 study aimed to evaluate the addition of pembrolizumab to standard intensive chemotherapy as frontline therapy for patients with newly-diagnosed acute myeloid leukemia (AML), including those with AML arising from previous myelodysplastic syndrome or post cytotoxic therapy.
Trial design
The BLAST MRD AML-1 study (NCT04214249) was a Phase 2, randomized trial that enrolled 49 participants. The study investigated pembrolizumab in combination with intensive chemotherapy as frontline therapy for patients with newly-diagnosed Acute Myeloid Leukemia, including those with Acute Myeloid Leukemia Arising From Previous Myelodysplastic Syndrome, Acute Myeloid Leukemia Post Cytotoxic Therapy, and Secondary Acute Myeloid Leukemia. Participants were assigned to either Arm I, receiving cytarabine, idarubicin or daunorubicin, pembrolizumab, and hematopoietic stem cell transplant (HSCT), or Arm II, receiving cytarabine, idarubicin or daunorubicin, and HSCT. The primary outcomes were not explicitly detailed in the posted results.
Key results
The trial results showed varying rates for minimal residual disease (MRD) negativity and complete response (CR)/complete remission with incomplete recovery (CRi) across the study arms.
- For the outcome of 'Rate of Minimal Residual Disease (MRD) Negative - Complete Response (CR)/Complete Remission With Incomplete Recovery (CRi)': 9 Participants in Arm I (with pembrolizumab) achieved this, compared to 11 Participants in Arm II (standard therapy).
- For 'Rate of MRD-negative CR': 11 Participants in Arm I (with pembrolizumab) achieved this, compared to 10 Participants in Arm II (standard therapy).
- For 'Rate of CR/CRi': 13 Participants in Arm I (with pembrolizumab) achieved this, compared to 12 Participants in Arm II (standard therapy).
- For 'MRD Negativity': 10 Participants in Arm I (with pembrolizumab) achieved this, compared to 6 Participants in Arm II (standard therapy).
- For 'Percentage of Patients With MRD-CR Using a MRD Cutoff of 0.01%': 8 Participants in Arm I (with pembrolizumab) achieved this, compared to 10 Participants in Arm II (standard therapy).
Statistical analyses, primarily using the Chi-squared method for various outcomes, yielded p-values of 0.77, 0.57, and 0.22, indicating no statistically significant differences between the treatment arms for the measured outcomes.
What this means
The posted results from the BLAST MRD AML-1 study suggest that adding pembrolizumab to standard intensive chemotherapy in newly-diagnosed acute myeloid leukemia patients did not significantly improve rates of minimal residual disease negativity or complete response compared to standard therapy alone. The lack of statistically significant differences across multiple outcome measures, as indicated by the high p-values from the Chi-squared analyses, suggests that further investigation may be needed to determine the role of pembrolizumab in this specific frontline setting for AML.
Source
The information for these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT04214249, titled 'BLAST MRD AML-1: BLockade of PD-1 Added to Standard Therapy to Target Measurable Residual Disease in Acute Myeloid Leukemia 1- A Randomized Phase 2 Study of Anti-PD-1 Pembrolizumab in Combination With Intensive Chemotherapy as Frontline Therapy in Patients With Acute Myeloid Leukemia,' were posted on 2026-03-04 on clinicaltrials.gov.