Omisirge

Omisirge (full biological name omidubicel-onlv) is an individualized infusion that may be given to adults and children aged 12 and older with blood cancer undergoing a stem cell transplant to quicken their neutrophil recovery rate and lessen their risk of infection. Omisirge is also used for severe aplastic anemia (SAA) after reduced intensity conditioning for patients aged 6 and older without a matched related donor.

• Omisirge is made from substantially modified donor cord blood.
• It is given following myeloablative conditioning (this is high-dose chemotherapy or radiation that kills cells in the bone marrow, including cancer cells, before the stem cell transplant).
• Myeloablative conditioning can weaken the immune system, increasing the risk of severe and potentially fatal infections.

Omisirge is made from the stem cells of donor umbilical cord blood, which have been specially treated with nicotinamide (NAM) to boost their number and functionality. This enhanced cord blood helps patients recover faster after a stem cell transplant and reduces the risk of infections compared to untreated cord blood. The correct technical term for Omisirge is nicotinamide (NAM) modified allogeneic hematopoietic progenitor cell therapy.

• Appropriate cord blood units are selected using the Omisirge search filter in MatchSource.
• A Gamida Cell Search Optimization Specialist can help your healthcare provider identify the appropriate CBU for Omisirge.
• Gamida Cell Assist provides support to patients, caregivers, and the hospital’s transplant team at each step of the process.

Omisirge gained FDA approval on April 17, 2023, for adults and children aged 12 and older with blood cancer undergoing a stem cell transplant. On December 5, 2025, FDA approval was extended to include the treatment of severe aplastic anemia (SAA).

Do not receive Omisirge if you are allergic to omidubicel-onlv, Omisirge, DMSO, gentamicin, Dextran 40, human serum albumin (HSA), or bovine material.

Tell your healthcare provider about all your medical conditions, including if you:

• have allergies to antibiotics
• have had infusion reactions before
• have experienced graft versus host disease before
• have an infection
• have a genetic disorder
• are pregnant or planning to become pregnant
• are breastfeeding.

Pregnancy and breastfeeding

There are no human or animal data regarding the use of Omisirge during pregnancy. It should only be used if the potential benefits outweigh the potential risks to the unborn child.

There are no data regarding the use of Omisirge during breastfeeding.

Most Common Side Effects

The most common side effects of Omisirge are:

• infections
• graft versus host disease
• infusion reactions.

Serious Side Effects and Warnings

Omisirge carries a Boxed Warning for infusion reactions, graft versus host disease (GvHD), engraftment syndrome, graft failure, and autoimmune cytopenias.

Infusion reactions (Boxed Warning)

Infusion reactions, some of which have been fatal, have occurred during or following an Omisirge infusion; 47% of patients in clinical trials experienced one. Your healthcare provider will consider premedicating you before your infusion with acetaminophen, antihistamines, and/or corticosteroids to reduce your risk of these reactions. Most reactions begin within minutes of the start of the infusion. Your healthcare provider will also monitor you throughout the infusion.

• You should not receive Omisirge if you are allergic to dimethyl sulfoxide (DMSO), Dextran 40, gentamicin, human serum albumin, or bovine material.
• Tell your healthcare provider right away if you experience any of the following signs or symptoms: your gums feel inflamed, you have difficulty swallowing, fever, chills, fatigue, fast heart rate, shortness of breath, severe nausea, severe vomiting, diarrhea, muscle pain, joint pain, low blood pressure, high blood pressure, or dizziness/lightheadedness.

Graft-versus-Host-Disease (Boxed Warning)

This is a serious complication that has been reported following Omisirge treatment, where the donor cells perceive the recipient's tissues as foreign and initiate an immune response against them. Tell your healthcare provider immediately if you experience any signs and symptoms suggestive of graft vs host disease, including rash, diarrhea, or yellowing of the eyes.

Engraftment Syndrome (Boxed Warning)

This is associated with neutrophil recovery after Omisirge administration because Omisirge is derived from umbilical cord blood. Tell your healthcare provider right away if you develop an unexplained fever, rash, headache, breathing problems, cough, or weight gain because corticosteroids may be needed.

Primary Graft Failure (Boxed Warning)

This is when the new stem cells do not make the white blood cells, red blood cells, or platelets that you need. This may be fatal.

Autoimmune Cytopenias (Boxed Warning)Autoimmune cytopenias have occurred following treatment of severe aplastic anemia. Tell your healthcare provider right away if you experience paleness, fatigue, fast heart rate, enlarged spleen, pinpoint round spots on the skin, easy bruising, prolonged bleeding from cuts, recurrent bacterial infections, persistent mouth ulcers, bleeding gums, or frequent fevers.

Allergic Reactions

These may occur with Omisirge administration. Serious hypersensitivity reactions, including anaphylaxis, may be due to DMSO, residual gentamicin, Dextran 40, human serum albumin (HSA), or bovine material contained in Omisirge.

Omisirge may also contain residual antibiotics if the cord blood donor was exposed to antibiotics while inside the mother. If you have a history of allergic reactions to antibiotics, your healthcare provider should monitor you during the infusion. Tell your healthcare provider right away if you develop any breathing difficulties, tightening of your airways, wheezing, itch, or hives.

Donor-Origin Cancers

Donor cell-derived cancers can occur, including post-transplant lymphoproliferative disorder (PTLD), a usually fatal lymphoma-like disease linked to the Epstein-Barr virus, and donor-derived myelodysplastic syndrome (MDS). Lifelong monitoring for secondary malignancies is required. After Omisirge treatment, patients must report any secondary cancer to Gamida Cell at (844) 477-7478.

Transmission of Serious Infections and Rare Genetic Diseases

Because Omisirge is made using stem cells from umbilical cord blood, there is a risk of transmission of infectious diseases or rare genetic diseases. Tell your healthcare provider if you develop a serious infection or a rare genetic disease.

This is not a full list of side effects. See the Omisirge Prescribing Information for a full list of side effects. To report side effects, contact Gamida Cell at (844) 477-7478 or the FDA at 1-800-FDA-1088.

Omisirge is administered via a one-off intravenous infusion.

• Omisirge is made especially for you. Each treatment course consists of one infusion and that infusion is tailor-made for you.
• Each patient-specific single dose consists of a Cultured Fraction (CF) and a Non-cultured Fraction (NF).
• The CF bag is administered first, followed by the NF bag within 1 hour after completion of the CF infusion.
• Patients receive premedication with an antihistamine, hydrocortisone, and acetaminophen approximately 30 to 60 minutes before receiving Omisirge.

Warning: There is an approximately 8% risk of a manufacturing failure. If this happens, a second manufacturing attempt may be considered.

• Additional chemotherapy may be required to cover the delay in making a new product which may increase the risks of adverse events during the preinfusion period.

There have been no drug interaction studies performed with Omisurge.

Omisirge is manufactured from umbilical cord blood using a laboratory process called proprietary nicotinamide (NAM) technology to enhance and expand the number of progenitor cells.

Omisirge is a cell suspension for intravenous infusion. A single dose of Omisirge consists of:

• A Cultured Fraction: At the time of cryopreservation, the CF contains a minimum of 8.0 × 108 total viable cells with a minimum of 8.7% CD34+ cells and a minimum of 9.2 × 107 CD34+ cells suspended in approximately 10% DMSO.
• A Non-cultured Fraction: At the time of cryopreservation, the NF contains a minimum of 4.0 × 108 total viable cells with a minimum of 2.4 × 107 CD3+ cells suspended in approximately 10% DMSO.

Each fraction is supplied separately in its own cryopreserved bag.

• Both bags diluted with their respective IS must be infused to achieve the dose of Omisirge.

Gamida Cell Inc. manufactures Omisirge.

• Omisirge is made in their fully licensed GMP manufacturing facility in Kiryat Gat, Israel.
• Time to delivery to U.S. transplant centers is within 30 days after the start of manufacturing.