Early Sirolimus-Based Immunosuppression is Safe for Lung Transplantation Patients: Retrospective, Single Arm, Exploratory Study

BACKGROUND: Sirolimus, a mechanistic target of sirolimus inhibitor, is an immunosuppression medication for patients undergoing heart and abdominal transplantation. Sirolimus-based immunosuppression administered de novo post-lung transplantation is associated with bronchial anastomosis healing-related complications. We hypothesized that sirolimus administration within the first postoperative month in selected lung transplant recipients is safe and may be associated with favorable short-term and long-term outcomes due to its anti-proliferative properties and minimal adverse side effects. MATERIAL/METHODS: Thirteen patients (13.3%; mean age, 46.8±11.9 years) received early sirolimus-based immunosuppression along with cyclosporine and prednisone; 10 patients received single-lung transplantation, 3 received double-lung transplantation, and all received induction immunosuppressants. Patients received early sirolimus-based immunosuppression after an uncomplicated postoperative course and detailed bronchoscopic assessment. RESULTS: Sirolimus was begun on a mean of 20.6±4.7 days postoperatively (range, 14–32 days). The in-hospital and 30-day mortality rate was 0%. At long-term follow-up, 5 patients died (due to bacterial infection in 4 patients and pneumocystis jiroveci pneumonia in 1 patient). The mean overall survival was 4.4±2.53 (range, 0.8–10.0) years, 1-year survival was 92%, and 5-year survival was 62%. In 4 patients (30.8%), sirolimus was stopped due to infection in 3 patients and re-transplantation in 1 patient. Only one of the 13 patients developed bronchiolitis obliterans syndrome. In patients still taking sirolimus, renal function, systolic blood pressure, and lipid profile were within normal ranges; however, these patients required statin therapy. CONCLUSIONS: In selected lung transplant recipients, early sirolimus-based immunosuppression is safe and associated with beneficial short-term and long-term outcomes.