Drug monitoring for mycophenolic acid in graft‐<i>vs</i>‐host disease prophylaxis in cord blood transplantation

Abstract

Aims We performed the retrospective analysis to clarify the significance of drug monitoring for mycophenolic acid (MPA), the active form of mycophenolate mofetil (MMF), in prophylaxis for graft‐ vs ‐host disease (GVHD) in cord blood transplantation. Methods We retrospectively analysed the data of 46 patients who underwent first cord blood transplantation and received GVHD prophylaxis with tacrolimus plus MMF. MPA levels were measured on days 7 and 21, and 24‐hour areas under the curve (AUC 0–24 ) were estimated. Results The engraftment and 3‐year overall survival rates of all patients were 94% and 78%, respectively. The cumulative incidence of sepsis before engraftment was higher in patients with AUC 0–24 on day 7 of &gt;60 μg h/mL than in other patients (33 vs 6%, P = .02). The cumulative incidence of grade II–IV acute GVHD was higher in patients with AUC 0–24 on day 21 of ≤30 μg h/mL than in other patients (80 vs 50%, P = .04). The cumulative incidence of human herpesvirus 6 reactivation was higher in patients with AUC 0–24 on day 21 of ≤48 μg h/mL (median) than in other patients (50 vs 19%, P = .03). Conclusion Blood level of MPA was associated with risk of acute GVHD and infection. A prospective trial evaluating the benefit of personalized MMF dosing using MPA levels is needed.