Reduced-intensity conditioning for allogeneic transplantation in classical Hodgkin lymphoma

Hodgkin lymphoma (HL) is a curable disease; however, 10-20% of patients experience relapsed/refractory disease. While autologous hematopoietic cell transplantation (auto-HCT) remains standard, a substantial proportion relapse, necessitating alternative strategies. Allogeneic HCT (allo-HCT) remains a potentially curative option and here we emphasize the role of reduced-intensity conditioning (RIC) in HL.

In this review, we compare the feasibility, efficacy, and safety of myeloablative conditioning (MAC) and RIC allo-HCT in relapsed/refractory HL. Additionally, we describe the evolving landscape of transplantation in HL with the use of novel agents, especially immune checkpoint inhibitors, the role of alternative donors especially for ethnic minorities, and the evolving literature on the role of post-transplant Cyclophosphamide (PTC) in improving outcomes.

Allo-HCT remains a potentially curative option for patients with relapsed/refractory HL. RIC allo-HCT has emerged as the preferred platform for most patients, offering a favorable balance between efficacy and tolerability by leveraging graft-versus-malignancy (GVM) effects while minimizing non-relapse mortality over myeloablative conditioning. The use of ICI in the first line has significantly altered post-transplant outcomes by enhancing GVM effects but also increasing the risk of graft-versus-host disease (GVHD). PTCy-based prophylaxis and optimized donor selection now enable the safer use of alternative donors without compromising outcomes.