The objective of the present study was to determine the impact of proton pump inhibitors (PPIs) on the pharmacokinetics and pharmacodynamics of mycophenolic acid (MPA).

PubMed, Embase, Web of Sciences, and Scopus were systematically searched to identify relevant studies reporting pharmacokinetic parameters [including trough concentration (C0), maximum concentration (Cmax), time to maximum concentration (Tmax), the dose-adjusted area under the concentration-time curve from time 0-12 hours (AUC0-12 h/D), and half-life (t1/2)], and pharmacodynamic outcomes of MPA (eg, acute graft rejection and adverse drug reactions), with and without PPI administration. Pooled effect estimates were calculated using a random-effects model.

Twelve studies involving 473 participants were eligible for inclusion, 11 of which were included in the meta-analysis. PPI exposure was significantly associated with lower C0 [mean difference (MD) = -0.62 mg/L; P = 0.003] lower Cmax (MD = -4.71 mg/L; P = 0.01), and longer Tmax (MD = 0.30 hours; P = 0.0001) of MPA. However, no significant association was observed between PPI exposure and AUC0-12 h/D, t1/2, or any pharmacodynamic outcomes. Based on subgroup analysis, it can be suggested that a significant association between PPI exposure and altered MPA pharmacokinetics was mainly associated with mycophenolate mofetil but not enteric-coated mycophenolate sodium.

Coadministration of PPIs and mycophenolate mofetil significantly altered the pharmacokinetics of MPA, particularly by decreasing MPA absorption. However, PPI-MPA interactions did not impact pharmacodynamic outcomes of MPA.