Mycophenolate mofetil administered every 8 hours in combination with tacrolimus is efficacious in the prophylaxis of acute graft versus host disease in childhood, adolescent, and young adult allogeneic stem cell transplantation recipients.

BackgroundThe optimal dose and schedule of mycophenolate mofetil (MMF) in pediatric allogeneic stem cell transplant recipients remains to be determined. We previously reported safety and pharmacokinetics of MMF at 900mg/m(2) q6h dosing. This study was conducted to investigate the efficacy of tacrolimus plus q8h MMF dosing for acute graft versus host disease (GVHD) prophylaxis in a heterogeneous population of children, adolescent, young adult allogeneic stem cell transplant recipients, utilizing multiple allogeneic donor sources. ProcedureGVHD prophylaxis consisted of tacrolimus 0.03-0.04mg/kg/day intravenous continuous infusion or 0.12-0.16mg/kg/day orally divided q8-12h and MMF 900mg/m(2)/dose (max. 1.5g) or 15mg/kg/dose intravenous/orally (age 18 years) q8h starting on Day +1. MMF was discontinued on Day +30 or Day +60 in the absence of acute GVHD. Thirty-five children, adolescents, and young adult allogeneic stem cell transplant recipients with malignant and nonmalignant disorders were enrolled. ResultsKaplan-Meier probability of grade II-IV and grade III-IV acute GVHD was 22.8% (CI95: 5.2-47.9 [where CI stands for confidence interval]) and 5.7% (CI95: 0-48.9), respectively. Probability of extensive and limited chronic GVHD was 22.6% (CI95: 3.4-52.2) and 12.2% (CI95: 0.3-45.7), respectively. Probability of 1 year overall survival was 82% (CI95: 64.1-99.8). Myeloablative conditioning was predictive of higher risk of acute GVHD in the univariate analysis (P=0.01, hazard ratio = 6.6, CI95: 0.91-48). ConclusionThis study demonstrated a low probability of acute and chronic GVHD in a diverse cohort of childhood, adolescent, and young adult allogeneic stem cell transplant recipients following MMF q8h plus tacrolimus prophylaxis.