Posttransplant cyclophosphamide: a universal graft versus host disease prophylaxis

Area of Science:

• Hematopoietic stem cell transplantation
• Immunosuppression strategies
• Graft-versus-host disease prophylaxis

Background:

• Posttransplant cyclophosphamide (PTCY) combined with calcineurin inhibitors and mycophenolate was initially developed for haploidentical (HAPLO) stem cell transplants.
• PTCY has demonstrated significant efficacy in preventing GvHD in HAPLO transplants globally over the past decade.

Purpose of the Study:

• To review current GvHD prophylaxis strategies utilizing PTCY in patients with hematologic disorders.
• To address key questions regarding PTCY use, including cardiac toxicity, optimal dosing, timing, and use with antithymocyte globulin (ATG).
• To explore the role of PTCY in human leukocyte antigen (HLA)-identical grafts and its impact on engraftment, infections, and leukemia relapse.

Main Methods:

• Review of current literature and clinical practices regarding PTCY in GvHD prophylaxis.
• Analysis of data addressing specific clinical questions related to PTCY efficacy and safety.
• Discussion of PTCY's application in various transplant settings, including HAPLO and HLA-identical grafts.

Main Results:

• PTCY is highly effective in preventing GvHD, particularly in mismatched grafts.
• PTCY is increasingly being investigated and used in HLA-identical stem cell transplants.
• Ongoing research focuses on optimizing PTCY protocols, including dose, timing, and combination with other agents.

Conclusions:

• PTCY is a cornerstone of GvHD prevention across different transplant platforms.
• Further prospective trials are needed to refine PTCY dosing and scheduling for improved outcomes.
• PTCY offers a customizable approach to GvHD prophylaxis, balancing efficacy with potential toxicities.