Lung Transplant Outcomes Based on Immunosuppressive Regimen at Discharge: Data from the US Scientific Registry of Transplant Recipients (SRTR)

Abstract

<h3>Purpose</h3> There is currently no FDA approved immunosuppressive regimen for lung transplant (Tx) recipients; however, patients routinely receive a CNI-based regimen. The SRTR database was analyzed to provide real-world evidence of the efficacy and safety of tacrolimus-based immunosuppressive regimens post lung Tx. <h3>Methods</h3> Adult and pediatric recipients of a primary deceased donor lung Tx between January 1, 1999 and December 31, 2017 were followed for 3 years post-transplant based on immunosuppressive regimen at discharge: immediate-release tacrolimus (TAC IR)+mycophenolate mofetil (MMF), TAC IR+azathioprine (AZA), cyclosporine (CYA)+MMF, or CYA+AZA. The primary outcome was the composite endpoint of graft failure or death (all cause) at 1 year post-transplant. Cox proportional hazard models were used to test for baseline characteristics associated with a greater risk of graft failure or death in adults. <h3>Results</h3> Data were available for 26,080 lung Tx recipients (25,355 adults and 725 pediatric patients). The most common discharge immunosuppressive regimen was TAC IR+MMF in both groups. Post-transplant outcomes are shown in Tables 1 (adults) and 2 (pediatrics). Factors associated with a greater risk of graft failure or death in adults on TAC IR+MMF included: recipient age ≥65 years, single lung transplant, hospital stay >24 days, BMI <18.5 kg/m², serum creatinine ≥1.0 mg/dL, donor age ≥55 years, and donor race (Black). The risk of graft failure or death was significantly greater in adults receiving CYA+MMF or CYA+AZA compared to TAC IR+MMF. <h3>Conclusion</h3> Discharge immunosuppressive regimens in lung Tx recipients changed over the period from 1999-2017, with a substantial increase in the use of TAC IR+MMF. Adult and pediatric lung Tx recipients receiving TAC IR+MMF had a cumulative incidence of graft failure or death at 1 year post transplant less than 9% (graft survival >91%) and had the lowest rejection rates without increased risks of infection or malignancy.