Antithymocyte globulin therapy in chronic lung allograft dysfunction.

Introduction: Lung transplantation has seen strides in survival over the past few decades, though long-term survival remains poor. Chronic lung allograft dysfunction (CLAD) is a leading cause of graft failure and mortality beyond the first year. Anti-thymocyte globulin (ATG) is commonly used for treating refractory CLAD, though its efficacy remains uncertain. Methods: This retrospective study evaluated the impact of ATG on lung function decline and mortality among lung transplant recipients diagnosed with CLAD, defined as a persistent >20% decline in forced expiratory volume (FEV1) from baseline. Patients treated with ATG were compared to those who did not receive ATG, using mixed effects modeling for FEV1 decline and Fine-Gray competing risk modeling for mortality. Results: Of the 124 patients with CLAD, 55 (44%) received ATG. Administration was not associated with a significant change in FEV1 decline when compared to rate of decline prior to ATG administration [-0.0881 L/year, 95% CI (-0.21, 0.034)] or compared to non-ATG recipients [0.0599 L/year, 95% CI (-0.057, 0.18)]. However, ATG was associated with a lower hazard of all-cause mortality [subhazard ratio 0.66, 95% CI (0.39-1.14)]. Discussion: While ATG improved survival, it did not alter lung function decline, affirming the need for prospective randomized studies.