MC0518 is a treatment being tested in this trial. It consists of mesenchymal stromal cells, which are a type of cell that can help reduce inflammation and support healing. This therapy is being studied to see if it can improve outcomes for patients who have not responded to steroid treatments for acute graft-versus-host disease, a condition that can occur after a stem cell transplant.

Best Available Therapy (BAT) refers to the standard treatments currently used for managing acute graft-versus-host disease when steroids are not effective. This can include a variety of medications and approaches that are considered the most effective options available based on current medical knowledge and practice. The trial is comparing the new treatment, MC0518, to these existing therapies to see which is more effective.

Steroid Refractory Acute Graft Versus Host Disease – This condition occurs when the body of a transplant recipient attacks the donated cells, tissues, or organs, and does not respond to standard steroid treatments. It typically arises after a bone marrow or stem cell transplant. The disease primarily affects the skin, liver, and gastrointestinal tract, leading to symptoms such as rash, jaundice, and diarrhea. The progression of the disease can vary, with some patients experiencing mild symptoms while others may have severe organ involvement. The condition is considered acute when it develops within the first 100 days post-transplant. Management of this disease focuses on controlling the immune response to prevent further damage to the recipient’s body.