Rabbit anti-thymocyte globulin induction therapy does not prolong survival after lung transplantation

Background: Lung transplant survival is limited by the development of bronchiolitis obliterans syndrome (BOS). The strongest risk factor for BOS is acute rejection (AR). We have previously shown that rabbit anti-thymocyte globulin (RATG) induction therapy is associated with a decrease in early AR. Thus, we hypothesized that RATG induction would translate to reduced BOS and improved long-term graft survival. Methods: Forty-four lung recipients were prospectively randomized to receive conventional immunosuppression with RATG induction (RATG group) or conventional immunosuppression alone (control group). End-points included graft survival, early and total acute rejection, BOS and treatment complications. Results: There was no difference in graft survival between the groups at 8 years (RATG: 36%; control: 23%; P = 0.48). The RATG group had fewer early rejections compared with the control group (5% vs 41%; p = 0.01). However, the overall rejection incidence did not differ (RATG: 62%; control: 68%; p = 0.52). There was a trend toward a delay in BOS onset among RATG subjects compared with control subjects ( 2,376 days vs 1, 108 days; log rank, p = 0.15). There was no difference in the incidence of infections, but the RATG group had a higher rate of malignancies. Conclusions: Our results suggest that alternative approaches to anti-thymocyte induction should be pursued to reduce BOS and prolong allograft survival.