Kidney Res Clin Pract.  2020 Dec;39(4):479-486. 10.23876/j.krcp.20.059.

The impact of omeprazole on mycophenolate pharmacokinetics in kidney transplant recipients

• AbdElhalim MS
• Kenawy AS
• El Demellawy HH
• Azouz AA
• Alghanem SS
• Al-Otaibi T
• Gheith O
• ElMonem MA
• Afifi MK
• Hussein RRS

• KMID: 2509809
• DOI: http://doi.org/10.23876/j.krcp.20.059

Abstract

Background
The absorption rates of mycophenolate mofetil (MMF) and enteric-coated mycophenolate sodium (EC- MPS) may be influenced by the concomitant use of omeprazole.
Methods
One hundred kidney transplant patients were recruited during their outpatient visits, including 50 on MMF and 50 on EC-MPS. At the clinic, a predose mycophenolic acid (MPA) sample (C₀) was collected; subsequently, the participants received the proton-pump inhibitor omeprazole along with either MMF or EC-MPS. Two more blood samples were collected at 1.5 and 3.5 hours and used to estimate an area under the curve (AUC) from zero to 12 hours [AUC (0_-12)].
Results
The mean number of months after transplant was 92 months. The median AUC (0_-12) and C₀ results were 62.2 mg·h/L and 2.0 mg/L for the MMF group and 71.9 mg·h/L and 1.8 mg/L for the EC-MPS group (P = 0.160 and 0.225, respectively). Interestingly, 54% of the MMF group and 62% of the EC-MPS group showed AUCs above the target values. The correlation between MPA C₀ and the predicted AUC was poor in both groups.
Conclusion
Omeprazole can be safely co-administered with either MMF or EC-MPS, as it did not compromise the MPA exposure. Unexpectedly, however, a high percentage of patients presented MPA AUCs exceeding the target value, highlighting the importance of periodically assessing MPA level.

Keyword

Area under curve; Enteric-coated mycophenolate sodium; Kidney transplantation; Mycophenolate mofetil; Mycophenolic acid; Omeprazole