Supplementary Material for: A Multi-national Survey on Immunosuppressive Regimens and Mycophenolate Monitoring Practices After Kidney Transplantation

Abstract:
Background: Kidney transplantation (KT) offers substantial improvements in both survival and quality of life compared to dialysis in patients with end-stage kidney disease. However, the success of KT is critically dependent on effective immunosuppression. There has been improvement in short-term graft survival outcomes, but chronic rejection and cumulative drug toxicities continue to present significant challenges. Regarding immunosuppression monitoring strategies, calcineurin inhibitor trough concentrations is a standard practice, but for the mycophenolate mofetil (MMF), fixed dosing remains widespread despite considerable evidence supporting for dose optimization based on mycophenolic acid (MPA) area under the curve (AUC) monitoring. To elucidate current immunosuppressive practices and mycophenolate dosing strategies, we conducted a survey of multiple transplant centers in India, Australia, and New Zealand.
Methods: An internet-based questionnaire was sent via professional societies and direct correspondence to practitioners across Australia, New Zealand and India.
Results: We received responses from 142 centers across the three regions. Most respondents (90%) reported use of antibody induction therapy in standard risk recipients. Maintenance immunosuppression overwhelmingly involved “triple therapy” with tacrolimus (98%), mycophenolate (78% as mycophenolate mofetil), long-term corticosteroid continuation (96%). Overall, 78% reported never using MPA concentrations to guide management, though with geographic differences: 90% of respondents from India reported never measuring MPA, compared to only 32% from Australia and New Zealand (p<0.001). Major reasons for not measuring MPA given were difficulty in attaining MPA concentrations (56%), cost (33%), and uncertainty around techniques to assess exposure and concentration targets (36%). Only a minority (11%) of respondents questioned the clinical value of monitoring in clinical care.
Conclusion: Across distinct geographic regions, immunosuppression regimen including tacrolimus, MMF and long-term corticosteroids in standard risk kidney transplant recipients was homogenous. MPA concentration measurement to guide therapy is rarely used in India, though not uncommon across Australia and New Zealand at least in specific circumstances. Overcoming practical barriers and ensuring accessible clinical guidance may provide opportunities to improve the uptake of MPA monitoring