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Item 1. Business

2026-03-18 compared with 2025-03-31 · 106 added, 158 removed, 526 unchanged (33% of the section changed)

We are a clinical-stage immuno-oncology company specializing in the development and commercialization of novel T cell-based immunotherapies for the treatment of hematological malignancies and solid tumor indications.

Harnessing millions of years of immunologic evolution, Marker’s multi antigen recognizing (“MAR”)-T cell technology (formerly known as multi-tumor associated antigen-specific T cells, or multiTAA) is designed to recognize and kill highly heterogeneous tumors without the need for genetic modifications.

We are a clinical-stage immuno-oncology company specializing in the development of novel T cell-based immunotherapies for the treatment of hematological malignancies and solid tumor indications.

Harnessing millions of years of immunologic evolution, Marker’s Multi Antigen Recognizing (“MAR”)-T cell technology is designed to recognize and kill highly heterogeneous tumors without the need for genetic modifications.

This approach selectively expands natural tumor-specific T cells from a patient’s/donor’s blood that are capable of recognizing a broad range of tumor associated antigens, or TAAs.

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Targeting multiple antigens simultaneously exploits the natural capacity of T cells to recognize and kill tumor targets via native T cell receptors (“TCR”), while limiting tumor adaptation/escape by antigen-negative selection or antigen down-regulation.

When infused into a patient with cancer, the MAR-T cells are designed to kill cancer cells expressing the TAA and potentially recruit the patient’s immune system to participate in the cancer killing process.

When infused into a patient with cancer, the MAR-T cells are designed to kill cancer cells expressing the TAA.

We licensed the underlying technology for MAR-T cell therapy from Baylor College of Medicine, or BCM, in March 2018.

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In those studies, BCM saw evidence of clinical benefit, expansion of infused cells, and decreased toxicity compared to other cellular therapies.

We are advancing two product candidates for 3 clinical indications as part of our MAR-T cell program for:

We anticipate to continue to advance two product candidates for 3 clinical indications as part of our MAR-T cell program for:

● Autologous MAR-T cell product for the treatment of lymphoma and pancreatic cancer (MT-601)

● Off-the-Shelf (OTS) product in various indications (e.g., MT-401-OTS)

● Off-the-Shelf (“OTS”) product in various indications (e.g., MT-401-OTS in AML or MDS)

We do not genetically engineer our MAR-T cell therapies and we believe that our product candidates are superior to T cells engineered with chimeric antigen receptors, or CAR-T, for several reasons including:

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For these reasons, we believe our endogenous T cell receptor-based therapies may provide meaningful clinical benefit and safety to patients with both hematological and solid tumors.

We believe that our manufacturing process allows additional modifications to expand MAR-T cell recognition of cancer targets.

We believe that the simplicity of our manufacturing process allows additional modifications to expand MAR-T cell recognition of cancer targets.

For example, we are assessing the potential of combining MAR-T cell products with other products.

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We developed MT-601, a MAR-T cell product capable of recognizing multiple target antigens expressed by the tumor, thereby limiting tumor adaptation by negative antigen selection or downregulation.

We are evaluating the safety and efficacy of MT-601 in a Phase 1, multicenter, open-label study (APOLLO) in participants with relapsed or refractory lymphoma who either failed or are ineligible for anti-CD19 CAR-T cell therapy.

We are evaluating the safety and efficacy of MT-601 in a Phase 1, multicenter, open-label study (APOLLO) in participants with relapsed lymphoma who either failed or are ineligible for anti-CD19 CAR-T cell therapy.

MT-601 is a MAR-T cell product that specifically targets six different tumor antigens upregulated in lymphoma cells (Survivin, PRAME, WT1, NY-ESO-1, SSX-2, MAGEA-4).

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In addition, Marker’s non-engineered MAR-T cell approach selectively expands natural tumor-specific T cells from a patient’s blood that can recognize a broad range of tumor antigens, minimizing the risk of mutagenesis.

In August 2022, the FDA cleared our IND application for MT-601 for the treatment of patients with relapsed/refractory non-Hodgkin lymphoma who have failed or are ineligible to receive anti-CD19 CAR-T cell treatment.

In August 2022, the FDA cleared our IND application for MT-601 for the treatment of patients with relapsed non-Hodgkin lymphoma who have failed or are ineligible to receive anti-CD19 CAR-T cell treatment.

The Phase 1 APOLLO trial was initiated in January 2023.

In June 2023, we reported first enrollment in the dose escalation stage of the Phase 1 study.

In December 2024, the Company provided an update on the progress and clinical observations from the Phase 1 study, with a data cutoff date of September 10, 2024.

In this update, clinical data was available for 9 patients from 5 clinical sites across the United States.

Study participants showed early objective responses with and without lymphodepletion.

However, immunomonitoring data confirmed that lymphodepletion enhanced the expansion and persistence of MAR-T cell clones in vivo.

In August 2025, the Company provided an update on the progress and clinical observations from the Phase 1 study, with a data cutoff date of June, 2025.

In this update, clinical data was available for a total of 24 B cell lymphoma patients from 7 clinical sites across the United States, including 15 patients with Non-Hodgkin Lymphoma (“NHL) and 9 patients with Hodgkin Lymphoma (“HL”).

At the time of the data cutoff, 12 NHL and 9 HL patients have been assessed.

Study participants showed objective responses and a favorable safety profile with and without lymphodepletion.

Key findings from the APOLLO study include:

● Safety – Infusion of MT-601 was well tolerated in all study participants, with no observation of immune-effector cell associated neurotoxicity syndrome (ICANS) and one reported Grade 1 cytokine release syndrome (CRS).

No dose limiting toxicities (DLTs) have been reported to date.

● Efficacy – In the first dose cohort, 7 out of 9 patients achieved objective responses (78%) at first response assessment, with 4 patients demonstrating complete response (CR;

44.4%) (Table 1).

● Time in Follow-Up – Long-term follow-up of 6 to 12 months is currently available for three patients (Table 2).

Ongoing follow-up visits are being conducted to assess the durability of responses.

All study participants are monitored closely to ensure comprehensive data collection and patient safety.

MT-601 shows objective responses at first disease assessment.

Prior Lines of

Response Rate at First

of Patients Treated

CR at First Assessment

CR, Complete Response.

Data as of September 10, 2024.

Duration of patient follow-up in Phase 1 APOLLO study;

Longest Follow-Up

Clinical Response

CR, Complete Response;

PR, Partial Response.

Data as of September 10, 2024.

To further validate these observations, additional patients are currently being enrolled in the Phase 1 study.

● Safety – The dose escalation portion of the study tested doses ranging from 100x10 6 -400x10 6 cells.

Infusion of MT-601 was well tolerated in all study participants, with no observation of immune-effector cell associated neurotoxicity syndrome (ICANS) and two reported Grade 1 cytokine release syndrome (“CRS”) events (fever;

no treatment was required).

No dose limiting toxicities (“DLTs”) or immune effector cell-associated neurotoxicity syndrome (“ICANS”) have been reported to date.

● Efficacy and Duration of Response – Eight out of 12 NHL patients achieved objective responses (66%), with 6 patients demonstrating complete response (“CR”) as best response (50%).

Durable responses were observed (range 3-24 months) with 5 NHL patients showing continued response over 6 months, including 3 patients with over 12 months durability.

Seven out of 9 HL patients had objective responses (78%), with 1 patient demonstrating CR (11%) highlighting the versatility of MT-601 across multiple histologies.

Based on these favorable safety and efficacy outcomes, the study has advanced to the dose expansion phase, evaluating MT-601 at the highest dose level in patients with Diffuse Large B Cell Lymphoma (“DLBCL”) who have relapsed after anti-CD19 CAR-T therapy or are ineligible for CAR-T treatment.

MT-601 for the Treatment of Pancreatic Cancer

We reported interim data for an ongoing Phase 1/2 clinical trial (TACTOPS) of the MAR-T cell therapy targeting five TAAs for the treatment of pancreatic adenocarcinoma being conducted by BCM.

In this trial, we have observed a clinical benefit with 4 of 13 patients (31%) showing objective responses in front-line unresectable or metastatic pancreatic cancer, which correlated with the post-infusion detection of tumor-reactive T cells in patient peripheral blood and within tumor biopsy samples in patients in the tumor-resection arm of the trial.

To date, we have not observed any cytokine release syndrome or neurotoxicity in this trial.

We reported data for a Phase 1/2 clinical trial (TACTOPS) conducted at Baylor College of Medicine demonstrating encouraging objective clinical responses and a disease control rate of 84.6% when combining MAR-T cells (targeting five TAAs) with frontline chemotherapy in patients with pancreatic cancer.

To date, no cytokine release syndrome or neurotoxicity have been observed in this trial (Musher BL, Vasileiou S, Smaglo BG et al, Nat Med, 2026).

In January 2022, the FDA granted orphan drug designation to MT-601 for the treatment of patients with pancreatic cancer.

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The PANACEA trial will include a dose escalation portion followed by a dose expansion portion.

We recently announced that the Company has been awarded a $9.5 million grant from the Cancer Prevention & Research Institute of Texas (CPRIT) and a $2 million grant from the NIH Small Business Innovation Research (SBIR) program to support the clinical investigation of MT-601 in patients with metastatic pancreatic cancer.

In 2024, the Company was awarded a $9.5 million grant from the Cancer Prevention & Research Institute of Texas (“CPRIT”) and a $2 million grant from the National Institutes of Health (“NIH”) Small Business Innovation Research (“SBIR”) program to support the clinical investigation of MT-601 in patients with metastatic pancreatic cancer.

With the support of these grants, we will be able to advance MT-601 in pancreatic cancer without affecting our operations in the ongoing study of MT-601 in patients with lymphoma.

MT-401 for the Treatment of Patients with AML and MT-401-OTS Program

MT-401 ARTEMIS Study:

In January 2024, we announced discontinuation of the Phase 2 ARTEMIS study to prioritize the MT-401-OTS program in patients with Acute Myeloid Leukemia (AML) and Myelodysplastic Syndromes (MDS).

The previous ARTEMIS study was investigating MT-401 (zedenoleucel), in post-allogeneic hematopoietic stem cell transplant (HSCT) patients with AML.

The study had three treatment arms, including patients with measurable residual disease (MRD), as well as patients with MRD negative complete remission or active disease.

The dose administered in this multicenter trial was up to 200 million cells every two weeks for up to three doses.

● In April 2020, the Orphan Product Development Office of the United States Food and Drug Administration, or the FDA, granted orphan drug designation to MT-401 (zedenoleucel), a MAR-T cell therapy that targets four TAAs, for the treatment of AML.

● The same MAR-T cell therapy has been well tolerated in an ongoing Phase 1 clinical trial in AML and myelodysplastic syndrome, or MDS, conducted by our strategic partner Baylor College of Medicine, or BCM.

● As reported in a 2021 publication by Lulla et al., 11 of the 17 patients in the adjuvant disease setting dosed with the MAR-T cell therapy after receiving an allogeneic HSCT were relapse free [median leukemia-free survival, or LFS, not reached at a median follow-up of 1.9 years], with 11 of 15 patients (two patients were each treated during two different remissions) remaining alive (estimated two-year overall survival of 77%) at a median follow-up of 1.9 years post-infusion, which compares favorably with HSCT outcomes for risk-matched AML/MDS patients post-HSCT [median LFS of nine to 15 months and two-year survival probability of 42%].

● Additionally, eight patients were treated for active disease that was resistant to salvage therapy post-HSCT with a median of five prior lines of therapy (range:

o One of the eight patients crossed over from the adjuvant group, while two patients enrolled twice, but all three patients had active AML that failed another line of salvage therapy after their first MAR-T cell infusion.

o Two of the eight patients achieved objective responses, with one complete response and one partial response, with six patients continuing with stable disease.

o We have observed evidence of a patient’s natural immune system participating in cancer killing (epitope spreading) after infusion of our MAR-T cell therapy.

In 2021, the ARTEMIS trial conducted by Marker has completed the safety lead-in portion, which tested the comparability of MT-401 or zedenoleucel, the MAR-T cell product manufactured using peptides from two different vendors and enrolled six patients with active disease:

one measurable residual disease (MRD) positive patient and five frank relapse patients.

● Consistent with the results of the BCM Phase 1 trial, there were no dose-limiting toxicities, cytokine release syndrome or neurotoxicity observed in this stage of the trial.

Correlative studies showed that the patient saw significant expansion of infused MAR-T cells.

There were no objective responses from the frank relapse patients.

By November 2022, all six patients had completed dose-limiting toxicity (DLT) periods with no DLTs reported.

● In the fourth quarter of 2021, the manufacturing of MT-401 for the Phase 2 trial started at the Marker Cell Therapy cGMP manufacturing facility, named MCTF01.

We transitioned to treating patients using MT-401 manufactured with Marker’s new T cell manufacturing process.

The improved manufacturing process greatly reduced the manufacturing time and increased both the antigen specificity and diversity.

Specifically, the new process involves an improved T cell manufacturing process for MT-401 that reduces production time to 9 days (compared to the original process of >30 days).

This allows a 90% decrease in the number of interventions during production and an improved final T cell product compared to the original product used in previous clinical trials on MAR-T cells.

● After completing the safety lead-in portion, we initiated the remainder of the Phase 2 trial in July 2021.

Group 1 comprised adjuvant (disease-free) patients, with the primary endpoint of relapse-free survival of patients randomized to receive MT-401 versus a control group.

Group 2 comprised active disease patients in 2 single arm cohorts (MRD+ only and active disease), with primary endpoints of complete remission and duration of complete remission.

We were previously awarded grants from the FDA Orphan Products Grant program ($2 million), NIH Small Business Innovation Research (SBIR) program ($2 million) and the Cancer Prevention and Research Institute of Texas (CPRIT, $13 million), to support the Phase 2 clinical trial of MT-401.

All funding agencies have agreed to continue their financial support and to shift funds to the MT-401-OTS program.

Off- the-Shelf MT-401 (MT-401-OTS) for the Treatment of AML and MDS:

Marker previously announced that it intends to focus on the advancement of the MT-401-OTS program in patients with Acute Myeloid Leukemia (AML) and Myelodysplastic Syndromes (MDS).

MT-401-OTS has the potential to provide treatment to patients in as little as 72 hours.

Marker believes that this fast turnaround time would be beneficial for treating patients with rapid cancer progression, such as patients with measurable residual disease (MRD) in the AML setting.

In the OTS program, we intend to dose patients using “banked” products based on partially human leukocyte antigen (HLA) matching.

FDA has cleared our clinical protocol to investigate MT-401-OTS as a treatment in patients with AML.

We already established a cellular inventory manufactured from healthy donors, with ongoing efforts to further expand the inventory.

At full scale production, we estimate a single donor could provide treatment for approximately 40 patients, and the current stability program indicates that OTS MAR-T cell products are stable for more than a year in liquid nitrogen, which we expect will permit future on-demand availability for broad-scale implementation.

We expect to dose the first patient in the second half of 2025, and, if our OTS program shows promising results in the clinic, we intend to expand the OTS platform to other hematological malignancies and solid tumors.

With the grant support from the FDA Orphan Products Grant program, NIH Small Business Innovation Research (SBIR) program and the Cancer Prevention and Research Institute of Texas (CPRIT), the Company will be able to advance MT-401-OTS without affecting the investigation of its lead asset, MT-601, in patients with lymphoma.

MT-401-OTS Program

Since January 2024, Marker has been advancing MT-401 in an OTS program in patients with AML or MDS in the Phase 1 RAPID study.

MT-401-OTS has the potential to provide a fast treatment option for patients with rapidly progressing diseases.

The Company believes that using commercially available leukapheresis material from heathy donors can facilitate large-scale manufacturing and expedite treatment as fast as 72 hours, while also enabling broader scalability and accessibility of cell therapies at a lower per-dose cost.

We have established a cellular inventory manufactured from heathy donors, and anticipate that a single donor could provide treatment for approximately 40 patients.

In October 2025, the Company announced that the first patient has been treated in the OTS program, with encouraging preliminary safety data.

This observation is consistent with the favorable safety profile and tolerability previously reported for MAR-T cells.

The OTS product will be initially investigated in patients with AML or MDS, with the potential to be expanded to other indications.

With the grant support from the FDA Orphan Products Grant program, NIH Small Business Innovation Research (“SBIR”) program and the Cancer Prevention and Research Institute of Texas (“CPRIT”), the Company will be able to advance the OTS program without affecting the investigation of its lead asset, MT-601, in patients with relapsed lymphoma.

Our clinical-stage pipeline is set forth below:

Our MAR-T cells are designed to enhance the capacity of non-engineered T cells to find and kill cancer by increasing the diversity and quantity of naturally occurring cancer killing T cells within the patient.

Our goal is to be the leader in the development and commercialization of transformative immunotherapies for the treatment of hematological malignancies and solid tumors.

Our MAR-T cells are designed to enhance the capacity of non-engineered T cells to identify and kill cancer by increasing the diversity and quantity of naturally occurring cancer killing T cells within the patient.

Our goal is to become a leader in the development and commercialization of transformative immunotherapies for the treatment of hematological malignancies and solid tumors.

We are developing a portfolio of highly differentiated T cell therapies utilizing the MAR-T cell platform that we believe has the potential to significantly disrupt the current cell therapy landscape, while substantially improving survival and quality of life for patients with cancers.

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● Expedite clinical development, regulatory approval, and commercialization of our lead product candidates.

Based on the results of the Phase 1 clinical trials of the MAR-T cell therapies conducted at BCM and the positive clinical data from the Phase 1 APOLLO study, we plan to prioritize the advancement of MT-601 in patients with lymphoma and to advance the MT-401-OTS program in patients with AML and MDS.

Based on the encouraging clinical data from the Phase 1 APOLLO study, we are prioritizing the advancement of MT-601 in patients with relapsed lymphoma and plan to advance the OTS program initially in patients with AML or MDS, with the potential to be expanded to other indications.

We intend to initiate future additional clinical trials in other tumor types based on emerging data.

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● Invest in our platform to maximize the beneficial outcomes for cancer patients.

We plan to explore new product opportunities by increasing and/or customizing the antigens we target to expand the indications in which the MAR-T cell products will be efficacious, including solid tumors or other hematologic malignancies.

Additionally, our research and development efforts may include the exploration of different doses and/or frequency of dosing and the relationship of these factors with potential therapeutic benefit.

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T Cell Therapy Overview

The field of adoptive cell transfer is currently comprised primarily of CAR and TCR engineered T cells and has emerged from principles of basic immunology to become a paradigm-shifting clinical immunotherapy.

T cell therapy, we believe has evolved as one of the most promising branches of immunotherapy.

The field of adoptive cell transfer is currently comprised primarily of chimeric antigen receptor (“CAR”) and T cell receptor (“TCR”) engineered T cells and has emerged from principles of basic immunology to become a paradigm-shifting clinical immunotherapy.

T cell therapy, which we believe has evolved as one of the most promising branches of immunotherapy.

T cell immunotherapy involves the infusion of T cells into a patient.

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TCRs and CARs have distinct signaling properties and antigen sensitivities.

TCRs recognize peptide fragments from proteins expressed either inside the cell or on the cell surface, which are presented to T cells via major histocompatibility complex molecules.

TCRs recognize peptide fragments from proteins expressed either inside the cell or on the cell surface, which are presented to T cells via major histocompatibility complex (“MHC”) molecules.

CARs are programmed to recognize a specific cell surface protein.

Because CARs are specific for a single antigen, or more precisely a single epitope within the single antigen, they are very narrowly focused and have limitations.

When a CAR-T cell product is applied to a

specific antigen of a heterogeneous disease, CAR-T cells may leave behind tumor cells that do not express the target antigen, which can lead to tumor relapse due to immune escape.

When a CAR-T cell product is applied to a specific antigen of a heterogeneous disease, CAR-T cells may leave behind tumor cells that do not express the target antigen, which can lead to tumor relapse due to immune escape.

Our approach is to avoid genetic engineering by relying upon the native T cell receptor, which has evolved over millions of years to provide T cells with an exquisite capacity to recognize and kill cancer cells.

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In addition, we received an Investigational New Drug (IND) cleared by the U.S.

FDA to investigate MT-601 in a Phase 1 trial in patients with pancreatic cancer in combination with first-line chemotherapy.

Off- the-Shelf (OTS) MAR-T cell therapies – The MT-401-OTS product targets WT1, NY-ESO-1, PRAME, and Survivin antigens (MT-401-OTS).

We plan to enroll patients that will be matched to the pre-manufactured inventory of MT-401-OTS products based on their human leukocyte antigen, or HLA.

FDA to investigate MT-601 in a Phase 1 trial in patients with pancreatic cancer in combination with frontline chemotherapy.

Off-the-Shelf (“OTS”) MAR-T cell therapies – The OTS product targets WT1, NY-ESO-1, PRAME, and Surviving antigens (MT-401-OTS).

Enrolled patients are matched to the pre-manufactured inventory of MT-401-OTS products based on their human leukocyte antigen (“HLA”).

Because the MT-401-OTS product inventory is pre-manufactured, the T cell product is delivered to the patient in a significantly shorter amount of time than a patient-specific T cell product.

While the blood source and the antigens for stimulation differ between the autologous and OTS therapies, the manufacturing process for each product is identical.

While the blood source and the antigens for stimulation differ between our autologous and OTS products, the manufacturing process for each product is identical.

Cancers are heterogeneous in their expression of antigens.

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Based on our observations in clinical trials in AML, pancreatic cancer, lymphoma, ALL and MM, we believe that the MAR-T cell therapies have the potential to mediate a meaningful anti-tumor effect, as well as significant in vivo expansion of T cells.

For example, in BCM’s Phase 1 clinical trial in lymphoma, there were complete responses, or CRs, in six of the fifteen evaluable patients with both Hodgkin lymphoma and non-Hodgkin lymphoma with active disease.

Significantly, no patient with a CR has subsequently relapsed with disease, whereas typically 30% or more of patients with CR in reported CAR-T studies relapse within one year.

In patient results

to date in this trial, observed therapeutic responses appear to be highly durable, with some patients being relapse-free beyond five years.

For example, in BCM’s Phase 1 clinical trial in lymphoma (TACTAL), there were complete responses, or CRs, in six of the fifteen evaluable patients with both Hodgkin lymphoma and non-Hodgkin lymphoma with active disease.

Significantly, no patient with a CR has subsequently relapsed with disease, whereas typically 30% or more of patients with CR in reported CAR-T studies relapse within one year (Vasileiou et al., J Clin Oncol, 2021).

In patient results to date in this trial, observed therapeutic responses appear to be highly durable, with some patients being relapse-free beyond five years.

In 2023, Marker treated the first patient in the Phase 1 APOLLO trial investigating the safety and efficacy of MT-601 in patients with lymphoma.

Marker recently reported that the first patient treated in this Phase 1 study achieved a complete response 8 weeks after the second dose of MT-601 and that the patient maintained complete response to treatment 6 months after initial infusion with MT-601.

Marker recently provided an update on the progress and clinical observations from the study highlighting durable objective responses and a favorable safety profile in relapsed lymphoma.

● Non-genetically modified T cells.

Unlike CAR and TCR-based approaches, the MAR-T cell therapy does not require genetic modification of T cells, a costly and complex process that significantly complicates the manufacturing of a patient product.

We believe our MAR-T cell therapy represent a safe alternative to CAR-T cells and can be manufactured at a fraction of the cost of a gene-modified T cell product, with substantially reduced complexity of manufacturing.

We believe our MAR-T cell therapy represents a safe alternative to CAR-T cells and can be manufactured at a fraction of the cost of a gene-modified T cell product, with substantially reduced complexity of manufacturing.

● Low incidence rate of adverse events.

As of January 2025, the MAR-T cell therapy was generally well tolerated by the patients across clinical trials in hematological and solid tumor indications, and no treatment-related adverse events, including neurotoxicity, were attributed to the use of MAR-T cell therapies to date.

This appears to compare favorably with published CD19 CAR-T studies that have been associated with substantial tolerability concerns, including a Phase 1 trial in which 95% of patients had Grade 3 or higher adverse events during treatment and current investigations by the FDA regarding the risk of CAR-T cell therapies to potentially induce secondary cancers.

As of February 2026, the infusion of MAR-T cells was generally well tolerated by the patients across clinical trials in hematological and solid tumor indications, and no dose limiting toxicities or neurotoxicity were attributed to the use of MAR-T cells to date.

This appears to compare favorably with published CD19 CAR-T studies that have been associated with substantial tolerability and safety concerns, and investigations by the FDA regarding the risk of CAR-T cell therapies to potentially induce secondary cancers.

● Capable of addressing a broad repertoire of cancer cells.

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The following clinical trials were conducted by BCM pursuant to our strategic alliance.

In each trial, correlative studies showed significant expansion of MAR-T cells, as well as evidence of epitope spreading against tumor-associated antigens that were not targeted by the MAR-T cell therapy.

Acute Myeloid Leukemia

To date, available treatments for post-transplant AML patients are limited and include donor lymphocyte infusion, which has an approximately 15% overall response rate but a 30% to 50% risk of severe and debilitating graft-versus-host disease.

The five-year mortality rate for patients who receive an allogeneic HSCT exceeds 50%, and patients who relapse after a transplant have a survival expectation of approximately 4.5 months.

BCM recently completed a Phase 1 AML/MDS clinical trial of the MAR-T cell therapy for the treatment of patients with post-transplant AML.

In this trial, patients in remission with high risk for relapse, as well as patients with active disease post-transplant were treated.

As reported in a 2021 publication by Lulla et al., 11 of the 17 patients in the adjuvant disease setting dosed with the MAR-T cell therapy after receiving an allogeneic HSCT did not relapse during the follow-up period of the study [median LFS not reached at a median follow-up of 1.9 years], with 11 of 15 patients (two patients were each treated during two different remissions) remaining alive (estimated two-year overall survival of 77%) at a median follow-up of 1.9 years post-infusion which compares favorably with HSCT outcomes for risk-matched AML/MDS patients post-HSCT [median LFS of nine to 15 months and two-year survival probability of 42%].

Additionally, eight patients were treated for active disease that was resistant to salvage therapy post-HSCT with a median of five prior lines of therapy (range:

four to ten).

One of the eight patients crossed over from the adjuvant group while two patients enrolled twice, but all three patients had active AML that failed another line of salvage therapy after their first MAR-T cell infusion.

Two of the eight patients achieved objective responses with one complete response and one partial response, with six patients continuing with stable disease.

In this trial, the MAR-T cell therapy was well tolerated, with no drug-related serious adverse events and no instances of greater than Grade 2 acute graft-versus-host disease or moderate-severe chronic GVHD.

The maximum grade treatment-related adverse event was seen in one patient in the adjuvant disease group who had a possibly drug-related Grade 3 elevation of liver enzymes but was treated with prednisone with complete resolution.

After discontinuing treatment and receiving decitabine, the patient relapsed and later re-enrolled in the trial in the active disease group and entered CR for 13 months and survived for 2.5 years.

In each trial, correlative studies showed significant expansion of MAR-T cells in vivo.

BCM evaluated MAR-T cells (5 TAA product) in a Phase 1 clinical trial for the treatment of patients with lymphoma.

A total of 32 patients received two protocol-specified infusions of MAR-T cells, 14 with Hodgkin lymphoma, or HL, and 18 with aggressive non-Hodgkin lymphoma, or NHL.

As reported in a publication by Vasileiou et al., BCM had treated 15 patients with active disease (active lymphoma group), all of whom had completed a follow-up period beyond three months post-infusion.

These patients were heavily pre-treated and had failed a median of five prior lines of therapy (range four to eight) for the HL patients and a median of three prior lines of therapy (range three to four) for the NHL patients.

As illustrated below, in the active lymphoma group, six patients achieved CR and nine patients had experienced stable disease.

None of the patients in CR had relapsed, and the range for the duration of CR in these patients was between two and over five years after being infused with MAR-T cells with the exception of one patient who died of an unrelated pneumonia while in a CR.

Responses in all six patients who entered CR were associated with an expansion of infused T cells, as well as induction of broad-based antigen spreading across many tumor-associated antigens.

BCM also treated 17 patients, including one patient who was treated a second time after a relapse, in remission (adjuvant lymphoma group).

Like the active lymphoma group, these patients were heavily pre-treated with seven patients with HL treated with a median of 4 prior lines of therapy (range:

three to five) and 10 patients with NHL with a median of three prior lines of therapy (range:

one to five).

As illustrated below, in the adjuvant lymphoma group, all 17 patients had entered CR, with 14 patients in continued complete remission, or CCR, without relapsing.

The duration of responses ranged from approximately nine months to over five years.

In both treatment groups, the MAR-T cells were well tolerated, with no drug-related serious adverse events.

Pancreatic Cancer

In May 2020, we reported interim data from an ongoing Phase 1/2 clinical trial of the MAR-T cell therapy for the treatment of pancreatic adenocarcinoma being conducted by BCM.

In May 2020, we reported interim data from an ongoing Phase 1/2 clinical trial investigating MAR-T cells for the treatment of pancreatic adenocarcinoma being conducted by BCM.

In 2020, we reported that in this trial, BCM administered MAR-T cells to a total of 31 patients with advanced or borderline resectable pancreatic adenocarcinoma in three arms:

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In patients responding to therapy, significant expansion of the infused MAR-T cell therapy was observed.

BCM evaluated the MAR-T cell therapy (5 TAA product) in a Phase 1 clinical trial for the treatment of patients with lymphoma.

A total of 32 patients received two protocol-specified infusions of MAR-T cells, 14 with Hodgkin lymphoma, or HL, and 18 with aggressive

non-Hodgkin lymphoma, or NHL, [diffuse large B-cell lymphoma, or DLBCL, (n=12), mantle cell lymphoma, or MCL, (n=2), T-cell lymphoma (n=3) and composite lymphoma (HL and DLBCL, n=1)].

As reported in a recent publication by Vasileiou et al., BCM had treated 15 patients with active disease (active lymphoma group), all of whom had completed a follow-up period beyond three months post-infusion.

As illustrated below, in the active lymphoma group, six patients entered CR and nine patients had experienced stable disease.

None of the patients in CR had relapsed, and the range for the duration of CR in these patients was between two and over five years after being infused with the MAR-T cell therapy with the exception of one patient who died of an unrelated pneumonia while in a CR.

Responses in all six patients who entered CR were associated with an expansion of infused T cells, as well as induction of broad-based antigen spreading across many tumor-associated antigens.

BCM also treated 17 patients, including one patient who was treated a second time after a relapse, in remission (adjuvant lymphoma group).

Like the active lymphoma group, these patients were heavily pre-treated with seven patients with HL treated with a median of 4 prior lines of therapy (range three to five) and 10 patients with NHL with a median of three prior lines of therapy (range one to five).

As illustrated below, in the adjuvant lymphoma group, all 17 patients had entered CR, with 14 patients in continued complete remission, or CCR, without relapsing.

The duration of response ranged from approximately nine months to over five years.

In both treatment groups, the MAR-T cells were well tolerated, with no drug-related serious adverse events.

Acute Myeloid Leukemia

The five-year mortality rate for patients who receive an allogeneic HSCT exceeds 50%, and patients who relapse after a transplant have a survival expectation of approximately 4.5 months.

BCM conducted a Phase 1 AML/MDS clinical trial investigating MAR-T cells for the treatment of patients with post-transplant AML.

In this trial, patients in remission with high risk for relapse, as well as patients with active disease post-transplant were treated.

As reported in a 2021 publication by Lulla et al., 11 of the 17 patients in the adjuvant disease setting dosed with the MAR-T cell therapy after receiving an allogeneic HSCT did not relapse during the follow-up period of the study, with 11 of 15 patients (two patients were each treated during two different remissions) remaining alive (estimated two-year overall survival of 77%) at a median follow-up of 1.9 years post-infusion which compares favorably with HSCT outcomes for risk-matched AML/MDS patients post-HSCT.

Additionally, eight patients were treated for active disease that was resistant to salvage therapy post-HSCT with a median of five prior lines of therapy (range:

four to ten).

Two of the eight patients achieved objective responses with one complete response and one partial response, with six patients continuing with stable disease.

In this trial, the infusion of MAR-T cells was well tolerated, with no drug-related serious adverse events and no instances of greater than Grade 2 acute graft-versus-host disease or moderate-severe chronic GVHD.

The maximum grade treatment-related adverse event was seen in one patient in the adjuvant disease group who had a possibly drug-related Grade 3 elevation of liver enzymes but was treated

with prednisone with complete resolution.

After discontinuing treatment and receiving decitabine, the patient relapsed and later re-enrolled in the trial in the active disease group and entered CR for 13 months and survived for 2.5 years.

Process Development and Manufacturing of the MAR-T Cell Therapies

In the manufacturing process, blood is drawn from either the individual patient (in the case of the autologous T cells) or from a healthy donors/commercially available leukapheresis material (in the case of the OTS program).

In the manufacturing process, blood is drawn from either the individual patient (in the case of the autologous T cells) or from healthy donors/commercially available leukapheresis material (in the case of the OTS program).

Although the T cells that are selected and expanded by our process exist in a patient’s circulating blood, these T cells are often present at very low frequencies.

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Upon release of the final patient product, the cells are frozen and transported to the site where the cells will be administered.

The standard dose for patients with lymphoma ranges from 100 to 400 million cells per adult patient.

Manufacturing

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We continue to contract and collaborate with BCM and others to perform a wide variety of services to ensure the continuation of our research and development efforts, with the goal of optimizing our manufacturing process, product quality and commercial scalability.

In July 2021, we opened an in-house cGMP manufacturing facility in Houston, Texas, where we manufactured the clinical supply of our product candidates.

Subsequently, on June 26, 2023, we completed a transaction with Cell Ready, LLC, or Cell Ready, pursuant to a Purchase Agreement, or the Cell Ready Purchase Agreement, dated May 1, 2023, by and between us and Cell Ready, pursuant to which we (i) assigned to Cell Ready the leases for our two manufacturing facilities in Houston, Texas, or the Manufacturing Facilities, (ii) sold to Cell Ready all of the equipment and leasehold improvements at the Manufacturing Facilities and (iii) assigned to Cell Ready our rights, title and interest in any contracts related to the equipment and Manufacturing Facilities (collectively referred to as the “Purchased Assets”).

Following the closing of the Cell Ready Purchase Agreement, we no longer operate our own cGMP manufacturing facility and instead rely on third parties for the clinical and, once approved, commercial manufacture of our product candidates.

As such, on February 22, 2024, we entered into a Master Services Agreement for Product Supply (the “MSA”) with Cell Ready for the provision of various products and services by Cell Ready pursuant to work orders that may be entered into from time to time.

Cell Ready, which is owned by one of our former directors and current shareholders, Mr.

On February 22, 2024, we entered into a Master Services Agreement for Product Supply (the “MSA”) with Cell Ready for the provision of various products and services by Cell Ready.

Cell Ready, which is owned by one of our former directors, Mr.

John Wilson, is a contract development and manufacturing organization (CDMO).

The MSA contains customary representations, warranties and indemnification provisions.

The initial term of the MSA is three years and may be extended upon the mutual written agreement of the parties.

On March 27, 2025, we mutually agreed with Cell Ready to terminate the MSA.

In connection therewith, we entered into a settlement and release agreement with Cell Ready pursuant to which we paid Cell Ready approximately $453,000 and we provided one another with mutual releases of all claims associated with any and all agreements between Marker and Cell Ready.

Additionally, BCM continues to supply us with products as we continue our clinical trials.

Furthermore, in anticipation of the commencement of our larger pivotal trial for Lymphoma in 2026, as well as the eventual need for commercial scale production, we intend to evaluate and qualify additional potential third-party manufacturing partners to provide potential multiple sources of clinical and commercial supply.

We currently are in discussions with a number of CDMO candidates and anticipate that we will select a partner organization and commence the qualification and technology transfer process later this year.

However, there is no guarantee that we will or have properly estimated our required manufacturing capacities or that the third parties on which we rely to manufacture our products will be able or willing to perform on our proposed timelines or to meet our manufacturing demands, if at all.

While BCM continues to supply us with products as we continue our clinical trials, in anticipation of the commencement of our larger pivotal trial for lymphoma in 2026, as well as the eventual need for commercial scale production, on June 16, 2025, the Company entered into a Statement of Work (the “SOW”) with Cellipont Bioservices (“Cellipont”), a leading cell therapy Contract Development and Manufacturing Organization (“CDMO”), for the manufacturing of MT-601, the Company’s lead MAR-T cell product.

Pursuant to the SOW, Cellipont will provide technology transfer and cGMP manufacturing services to support the scale-up and production of MT-601 for Marker’s APOLLO study.

demands, if at all.

If any of our third-party vendors experience disruptions, or otherwise cease or substantially reduce the amount of products they are willing to supply us, our business and operations could be adversely affected.

See “Risk Factors”.

During the years ended December 31, 2024 and 2023, the Company incurred $5.8 million and $1.3 million in expenses related to the services and manufacturing costs, and paid $5.5 million and nil related to invoices received, respectively.

During the years ended December 31, 2025 and 2024, we incurred $0.8 million and $5.8 million, respectively, in expenses related to Cell Ready services and manufacturing costs, as well as $0.5 million during the year ended December 31, 2025 in connection with the termination of the MSA as noted above.

During the years ended December 31, 2025 and 2024, we paid $2.6 million and $5.5 million, respectively related to Cell Ready invoices received.

During the years ended December 31, 2025 and 2024, we incurred $3.2 million and approximately $7,000, respectively, in expenses related to BCM services and manufacturing costs.

During the years ended December 31, 2025 and 2024, we paid approximately $3.0 million and $0.1 million related to BCM invoices received, respectively.

During the years ended December 31, 2025 and 2024, we incurred $0.7 million and nil, respectively, in expenses related to Cellipont services and manufacturing costs.

During the years ended December 31, 2025 and 2024, we paid $0.6 million and nil related to Cellipont invoices received, respectively.

We face competition from numerous pharmaceutical and biotechnology companies, as well as from academic institutions, private and public research institutions, and government agencies.

Treatment of relapsed patients with lymphoma remains a challenge with relatively low overall survival rates.

To date, there are four CD19-directed CAR-T cell therapies (Yescarta, Kymriah, Tecartus, and Bryanzi)

approved for patients with relapsed lymphoma.

To date, there are four CD19-directed CAR-T cell therapies (Yescarta, Kymriah, Tecartus, and Bryanzi) approved for patients with relapsed lymphoma.

However, up to 60% of CD19 CAR-T cell treated patients will relapse, particularly in the third line setting (Chong EA et al, N Engl J Med, 2021).

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(1) less than $500 million, (2) $500 million to $1.0 billion, (3) $1.0 billion and over, and (4) $2.0 billion and over.

The corresponding royalty percentages range from 0.65% to 5.0% - increasing in proportion to the aggregate net sales.

corresponding royalty percentages range from 0.65% to 5.0% - increasing in proportion to the aggregate net sales.

The royalty fee may be reduced in the event that we must pay additional royalties with respect to third-party owned patent rights or technology necessary for the use, manufacture or sale of a licensed product.

We also agreed to pay BCM up to an aggregate of $64.85 million in milestone payments upon the occurrence of nine particular milestones relating to completion of the first dosing in clinical trials for a first and second distinct product, receipt of approval from the FDA and the achievement of certain net sales goals.

We also agreed to pay BCM up to an aggregate of $64.85 million in milestone payments upon the occurrence of nine particular milestones relating to completion of the first dosing in the first Phase 3 clinical trial for a first and second distinct product, receipt of approval from the FDA and the achievement of certain net sales goals.

We are also responsible for sublicensing fees.

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Cancer Prevention and Research Institute of Texas

In August 2021, we received notice of a Product Development Research award totaling approximately $13.1 million from CPRIT to support our clinical investigation of MT-401.

In December 2024, we received notice of an additional $9.5 million grant from CPRIT to support the clinical investigation of MT-601 in patients with pancreatic cancer.

In August 2021, we received notice of a Product Development Research award totaling approximately $13.1 million from CPRIT to support our clinical investigation of MT-401 (the “CPRIT AML Grant”).

In December 2024, we received notice of an additional $9.5 million grant from CPRIT to support the clinical investigation of MT-601 in patients with pancreatic cancer (the “CPRIT Pancreatic Grant”).

Both CPRIT grants contain identical terms surrounding intellectual property and revenue sharing.

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If we are required to obtain a license from a third party to sell any such product, the revenue sharing percentages may be reduced.

once we have paid CPRIT 400% of the monies received under the grant agreements, we will continue to pay CPRIT a revenue-sharing percentage of 0.5% for the remainder of the Revenue Term as specified in the grant agreement.

In addition, once we have paid CPRIT 400% of the monies received under the grant agreements, we will continue to pay CPRIT a revenue-sharing percentage of 0.5% for the remainder of the Revenue Term as specified in the grant agreement.

Intellectual Property

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and (2) claims directed to therapeutic uses of such multi-antigen specific T cell products.

With regard to Cell Ready, the MSA provides that each party will solely and exclusively own all right, title and interest in and to their Background IP and all inventions derived from such Background IP (such invention being referred to as Foreground IP).

Background IP means all intellectual property either (a) owned or controlled by a party prior to the effective date of the MSA or (b) developed or acquired by a party independently from performance under the MSA without the use of, reliance on, or access to the other party’s confidential information.

Furthermore, pursuant to the MSA, Cell Ready grants to the Company a non-exclusive, perpetual, irrevocable, transferable, assignable, fully-paid up, royalty-free, worldwide license to and under any of Cell Ready’s Background IP and Foreground IP to the extent they are incorporated or embedded in any deliverables provided to the Company or in the process of generating or manufacturing such deliverables and reasonably necessary or useful for the Company to make, have made, manufacture, have manufactured, use, have used, offer for sale, sell, import, and otherwise exploit such deliverables.

The Company grants to Cell Ready until the termination or expiry of any applicable Work Order and for a period not exceeding the term of the MSA, a non-exclusive, fully paid-up, non-transferable, non-sublicensable limited license under and to the Company’s Background IP made available to Cell Ready pursuant to a Work Order solely to the extent required for Cell Ready to provide the services under such Work Order.

We believe our patent portfolio, together with our efforts to develop and patent next-generation technologies, provides us with a substantial intellectual property position.

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An enforceable patent with appropriate claim coverage can provide an advantage over competitors who may seek to employ similar approaches to develop therapeutics, and so the future commercial success of products, and therefore our future success, will be in part dependent on our intellectual property strategy.

We reassess the value of each patent at the time maintenance fees are due, and in cases where maintaining the patent is judged to be of no significant strategic value, we decline to pay the maintenance fee.

We reassess the

value of each patent at the time maintenance fees are due, and in cases where maintaining the patent is judged to be of no significant strategic value, we decline to pay the maintenance fee.

There can be no assurance that our patents, and any patents that may be issued, assigned, or licensed to us in the future, will afford protection against competitors with similar technology.

In addition, no assurances can be given that any patents issued, assigned, or licensed to us will not be infringed upon or designed around by others or that others will not obtain patents that we would need to license or design around.

If existing or future patents held by third parties and containing broad claims over technology used by us were upheld

by a court or other authority of competent jurisdiction, the holders of such patents could require us to obtain licenses to use such technology.

If existing or future patents held by third parties and containing broad claims over technology used by us were upheld by a court or other authority of competent jurisdiction, the holders of such patents could require us to obtain licenses to use such technology.

Patent coverage may also vary from country to country based on the scope of available patent protection.

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In the case of employees, the agreements provide that all inventions conceived by an employee shall be our exclusive property.

We currently have pending with the USPTO applications for registration of the trademarks “Marker Therapeutics.” We also have rights to use other names essential to our business.

In 2024, the USPTO has accepted the Statement of Use filed for the trademark application “Marker Therapeutics.” We also have rights to use other names essential to our business.

Federally registered trademarks have a perpetual life if they are maintained and renewed on a timely basis and used properly as trademarks, subject to the rights of third parties to seek cancellation of the trademarks if they claim priority or confusion of usage.

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● submission to the FDA of an IND, which must become effective before clinical trials may begin and must be updated annually or when significant changes are made;

● approval by an independent Institutional Review Board, or IRB, or ethics committee at each clinical site before the trial is commenced;

● approval by an independent Institutional Review Board, or IRB, or ethics committee at each clinical site before the trial may commence;

● performance of adequate and well-controlled human clinical trials to establish the safety, purity and potency of the proposed biologic product candidate for its intended purpose;

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At the state level, legislatures have increasingly passed legislation and implemented regulations designed to control pharmaceutical product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing.

Further, it is possible that additional governmental action is taken in response to the COVID-19 pandemic.

Product Liability and Insurance

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Corporate Information

We were incorporated under the laws of the State of Nevada in 1991 under the name “TapImmune, Inc.” and reincorporated in Delaware in October 2018 under the name “Marker Therapeutics, Inc.” Our principal executive offices are located at 2450 Holcombe Blvd, Suite BCM-A, MS:

BCM251, Houston, Texas, and our telephone number is (713) 400-6400.

Our common stock is listed for trading on the Nasdaq Capital Market under the symbol “MRKR”.

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Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 1. Business