Ossium's HOPE Program

Expanding Allogeneic HCT Access Through Organ Donor Bone Marrow

The gap between patients who need an allogeneic hematopoietic cell transplant (alloHCT) and those who actually receive one remains a persistent challenge in the field. Each year, approximately 18,500 patients in the US are diagnosed with life-threatening conditions where alloHCT is the optimal treatment, yet nearly half cannot access a transplant. Barriers include the rarity of certain HLA alleles, donor attrition and nonclearance, and prolonged procurement timelines that disadvantage patients with high-risk, rapidly progressing disease.

A novel graft source: Organ donor bone marrow

Ossium Health has developed the first centralized bank of cryopreserved bone marrow derived from deceased organ donors — a graft source that addresses several structural limitations of current living-donor and cord blood platforms simultaneously:

Donor pool: Ossium sources bone marrow from the hematopoietic cell-rich cancellous bone within the vertebral bodies of organ donors, through partnerships with Organ Procurement Organizations across the United States. This significantly expands the diversity and depth of the available donor pool.

CD34+ cell dose: Production of Ossium’s bone marrow yields more cells per donor than can be practically obtained from living donors, giving physicians the ability to select an optimal cell dose. The target cell dose in clinical use is 4-8 × 10⁶ CD34+ cells/kg, with a minimum of 3 × 10⁶ CD34+ cells/kg.

Time to transplant: Ossium’s cryopreserved product is available for on-demand shipment, allowing physicians to order and receive it within days rather than the weeks or months typically required to search and secure a living unrelated donor graft.

Published clinical data

Ossium is conducting PRESERVE I, a first-in-human study evaluating the safety and feasibility of cryopreserved deceased donor bone marrow in patients with hematologic malignancies who lack a suitable living donor.

To date, 23 patients have been treated with Ossium’s bone marrow across the PRESERVE I study and the HOPE expanded access program. Early clinical results are encouraging: data from the first four PRESERVE I patients showed rapid neutrophil engraftment, platelet recovery, and full donor chimerism. Acute GVHD in all cases was manageable with steroids, and no chronic GVHD was reported. By Day 180, all evaluable patients were alive and relapse-free. The first three patients treated under the HOPE program achieved neutrophil and platelet engraftment promptly, and full donor chimerism was confirmed for all three. Each case of acute GVHD was steroid-responsive and resolved, with no chronic GVHD. By Day 180, all evaluable patients were alive and relapse-free.

A peer-reviewed report published in Cytotherapy (January 2026) provides the most comprehensive description to date of Ossium’s GMP-manufactured cryopreservation platform, reporting strong early clinical data alongside evidence of production-scale consistency and long-term product stability.

Additional data reported at the 2026 Tandem Meetings included a graft rescue case in which off-the-shelf cryopreserved cadaveric marrow was used successfully in a myeloablative setting following the unexpected unavailability of a matched unrelated living donor — a scenario that will be recognizable to any high-volume transplant center.

Clinical use cases: where this graft source adds value

Growing experience with Ossium’s high-dose, off-the-shelf bone marrow has revealed several clinical scenarios where its on-demand availability and cell dose advantages are particularly meaningful:

• Primary graft failure — immediate availability makes it a viable rescue option without the delays inherent to re-engaging the living donor registry
• Secondary graft failure — may be considered on a case-by-case basis, particularly when DLI is not a practical option
• Donor attrition after conditioning — when a matched unrelated donor becomes unavailable after a patient has already begun myeloablative conditioning, off-the-shelf marrow can serve as timely rescue.
• High-risk MDS/AML requiring additional consolidation or salvage — for patients who cannot wait on a living donor’s schedule and need the flexibility to proceed to transplant when disease status allows
• Rare HLA types and poor match results — patients with 4/8 to 6/8 HLA matching for whom the unrelated donor pool offers limited or suboptimal options
• Severe aplastic anemia — where urgency and the need for adequate cell dose make the on-demand, high-dose characteristics of this graft particularly relevant

The HOPE Program: Expanded access outside the PRESERVE I study

For patients who cannot enroll in PRESERVE I due to eligibility criteria or logistical barriers, Ossium has established the HOPE Program (HPC Offered for PRESERVE Expansion), a structured expanded access program.

Patients aged 12–80 may be eligible if:

• Their treating physician has determined they are a candidate for allogeneic BMT, and
• The treating physician has determined that the potential benefit outweighs the potential risks.

To learn more, complete the form below or contact us at [email protected] or (628) 677-4863.

Request information about the HOPE Program:

Relevant publications and resources:

• Munjal S, et al. A First-in-Human Study of HLA-Partially to Fully Matched Allogeneic Cryopreserved Deceased Donor Bone Marrow Transplantation for Patients with Hematologic Malignancies. Transplantation and Cellular Therapy. 2026. DOI: 10.1016/j.jtct.2025.12.957
• Vasu S, et al. First Report of Successful, Lifesaving and Timely Graft Rescue Using an Off-the-Shelf Cryopreserved, Cadaveric Marrow in Myeloablative Transplant Following the Unexpected Unavailability of a Living Matched Unrelated Donor. Blood. 2025. DOI: 10.1182/blood-2025-7708
• Woods EJ, et al. Cryopreserved organ donor bone marrow achieves robust engraftment and chimerism in mismatched allogeneic transplantation. Cytotherapy. 2025. DOI: 10.1016/j.jcyt.2025.102006
• Munjal S, et al. High-dose cryopreserved bone marrow from deceased donors may reduce relapse in HLA-mismatched allogeneic transplantation: Day 180 post-transplant HOPE update. American Society of Hematology Annual Meeting. 2025. Abstract #5976
• Patel S, et al. Allogeneic Hematopoietic Cell Transplantation Using Deceased Donor Derived Cryopreserved Bone Marrow: A First-in-Human Report of Successful Engraftment in PRESERVE 1. European Hematology Association Annual Congress. 2025. Abstract PS2079
  

Ossium reserves the right to discontinue or change the terms of the Ossium HOPE Program (including the key patient criteria) at any time in its sole discretion. Ossium reserves the right to make the final determination regarding whether a patient meets the key patient criteria for the Ossium HOPE Program in its sole discretion.