Post-transplant AML Cell Therapy Receives $2 Million FDA Grant

Marker Therapeutics has received a $2 million grant from the FDA for the purpose of advancing the phase 2 ARTEMIS clinical trial (NCT04511130) for MT-401 (zelenoleucel), an investigational allogeneic multi-tumor-associated antigen (MultiTAA) T-cell therapy intended for the treatment of post-transplant acute myeloid leukemia (AML).^1,2

The grant will specifically help support the trial’s treatment arm for patients with post-transplant AML with minimal residual disease (MRD). MT-401 consists of donor-derived, non-engineered, selectively-expanded T-cells obtained via apheresis. It previously received orphan drug designation from the FDA in April 2020 for the treatment of patients with AML following allogeneic stem cell transplant.

"We are pleased to receive this Orphan Products award from the FDA to further clinical development of our multi-antigen targeted T-cell therapy in AML, a rare disease with limited treatment options after a stem cell transplant," Mythili Koneru, chief medical officer, Marker Therapeutics, said in a statement regarding the news.¹ “In our phase 2 ARTEMIS study for patients with post-transplant AML, we have observed promising results amongst the MRD+ patients, suggesting that MT-401’s unique and differentiated targeting technology can potentially reach MRD positive patients before relapse. This grant will enable us to further advance our development of MT-401 to potentially treat a patient population where no treatments have been approved. We look forward to further exploration in this patient population.”

The multicenter, open-label ARTEMIS study will enroll approximately 172 patients aged 18 years or older who are going to receive their first allogeneic hematopoietic stem cell transplant (HSCT) or who are experiencing their first relapse after allogeneic transplant. Participants are required to have a Karnofsky/Lansky score of at least 60, a life expectancy of at least 12 weeks, and adequate blood, liver, and renal function. Participants on experimental conditioning regimens before transplant may be included if no maintenance therapy is planned for after transplant. Patients with clinically significant or severely symptomatic intercurrent infections; patients who are pregnant or lactating; and patients who show evidence of grade 2 or greater graft versus host disease (GVHD) in the week before MT-401 administration, with the exception of stable grade 2 GVHD of the skin, will be excluded from the study.

Participants in the trial will be divided into 2 groups. The first (adjuvant) group will include approximately 120 patients screened prior to their HSCT with complete remission (CR) without MRD, who will be randomly assigned to either arm A or arm B. Patients in arm A will receive MT-401 at 90 days post-transplant, while patients in arm B will only receive standard-of-care observation. Meanwhile, the second (active disease) group will include patients who have experienced relapse at or prior to 90 days post-HSCT and crossover patients from group 1 arm B who develop relapse post-HSCT. Patients in this single-arm group, which is expected to include approximately 40 participants, will receive MT-401, and may also receive bridging therapy at the investigators’ discretion. The study’s primary end points are the number of participants with MT-401 dose limiting toxicities, relapse free survival for the adjuvant group, and CR and duration of CR for the active disease group. Overall survival (OS) and GVHD relapse-free survival will additionally be evaluated for the adjuvant group, and overall response rate, duration of response, OS, and progression-free survival will be evaluated for the active disease group. The study is recruiting at multiple locations throughout the United States and has an estimated completion date of July 2027.

“Today, adult patients with post-transplant AML have a 25 percent chance of 5-year survival,” Koneru said in an earlier statement when the first patient in the trial was dosed.³ “In various investigator-sponsored Phase 1 trials at the Baylor College of Medicine, our MultiTAA-specific T-cell therapies have been generally well-tolerated and demonstrated durable anti-cancer responses across a broad range of cancers—including post-transplant AML. Based on these results, we believe that MT-401 has the potential to become a meaningful treatment option for patients suffering from this disease."

REFERENCES

1. Marker Therapeutics awarded $2 million grant from U.S. FDA to support Marker’s phase 2 ARTEMIS trial of MT-401 in post-transplant AML. News release. Marker Therapeutics, Inc. September 13, 2022. https://ir.markertherapeutics.com/news-releases/news-release-details/marker-therapeutics-awarded-2-million-grant-us-fda-support 

2. Marker Therapeutics receives FDA orphan drug designation for its multi-antigen targeted T-cell therapy for acute myeloid leukemia. News release. Marker Therapeutics, Inc. April 29, 2020.https://ir.markertherapeutics.com/news-releases/news-release-details/marker-therapeutics-receives-fda-orphan-drug-designation-its 

3. Marker Therapeutics announces dosing of first patient in phase 2 trial of MT-401 in acute myeloid leukemia following stem cell transplant. News release. Marker Therapeutics, Inc. March 3, 2021. https://ir.markertherapeutics.com/news-releases/news-release-details/marker-therapeutics-announces-dosing-first-patient-phase-2-trial