Fludarabine + Melphalan + Methotrexate + Tacrolimus regimen

This is a combination therapy used in allogeneic hematopoietic stem cell transplantation (HSCT). The regimen consists of:

1. Fludarabine and Melphalan: These form the backbone of a reduced-intensity conditioning (RIC) regimen that helps prepare the patient's body for transplantation by suppressing the immune system and creating space for donor cells.

2. Tacrolimus and Methotrexate: These medications are used together for graft-versus-host disease (GVHD) prophylaxis after transplantation.

This combination has demonstrated efficacy in patients with acute myelogenous leukemia (AML), myelodysplastic syndromes (MDS), and other advanced hematological malignancies. Studies have shown that this regimen is associated with:

• Low treatment-related mortality (TRM)
• Moderate control of GVHD
• Good disease control without excessive non-relapse mortality (NRM)
• Favorable long-term overall survival (OS)

The regimen is particularly valuable for reduced-intensity conditioning, which allows transplantation in patients who might not tolerate more intensive myeloablative regimens due to age, comorbidities, or prior treatments.