Immunosuppression minimization is safe and associated with good long-term success in pediatric recipients of liver transplant

Immunosuppression reduction after liver transplant is an important strategy to mitigate long-term medication side effects. We describe our center's experience with immunosuppression minimization to once-daily calcineurin inhibitor dosing. Success was defined as continuing daily calcineurin inhibitor monotherapy with normal transaminases and no rejection. We performed a retrospective review of eligible children who received a liver transplant between 2009 and 2016, had a surveillance biopsy, and were on twice-daily calcineurin inhibitor monotherapy. Twenty-eight of 51 eligible patients were minimized to daily calcineurin inhibitor with goal 12-hour trough detectable. Nineteen patients (68%) had 1-year success, and 17 (61%) had long-term success at a median follow-up of 5.0 years (interquartile range (IQR): 2.9-6.6). Minimization failure occurred at a median of 0.6 years (IQR: 0.3-1.0) after dose reduction. Patients with long-term success had lower aspartate aminotransferase levels prior to minimization compared to those who failed with a median of 28.0 IU/L (IQR: 20.5-32.0) versus 32.0 IU/L (IQR: 30.0-37.0), p = 0.047. The long-term success group demonstrated a trend toward greater recipients of liver transplant from living donors (53% vs. 18%, p = 0.07). At the time of the last follow-up at a median of 5.0 years (IQR: 2.9-6.1) after surveillance biopsy, most (73%) patients who failed had returned to twice-daily calcineurin inhibitor monotherapy, all had liver enzymes <2 times the upper limit of normal, and there were no patient deaths or graft losses. In conclusion, immunosuppression minimization is safe in pediatric recipients of liver transplant and should be considered to reduce long-term medication side effects and improve patient quality of life. Future studies are necessary to follow long-term outcomes and develop biomarkers to predict minimization success.