Morbidity Rates With Reduced Mycophenolate Mofetil Dosage: A Single-Center Experience

Impact of Mycophenolate Mofetil Dose Reduction on Allograft Outcomes in Kidney Transplant Recipients on Tacrolimus-Based Regimens: A Systematic Review

OBJECTIVE

To systematically evaluate the clinical consequences of mycophenolate dose reduction in renal transplant recipients on tacrolimus-based regimens.

DATA SOURCES

PubMed (1949-July 2010), EMBASE (1980-July 2010), Cochrane Database of Systematic Reviews, International Pharmaceutical Abstracts, and Web of Science were searched using the terms mycophenolate mofetil, tacrolimus, dose reduction, and kidney and/or renal transplant. References from publications identified were reviewed.

STUDY SELECTION AND DATA EXTRACTION

Studies reporting on rejection rate, allograft survival, or renal function were included and ranked according to the US Preventive Services Task Force classification; excluded were studies that were dose-finding or used cyclosporine only, involved patients on enteric-coated mycophenolate sodium or those with multiorgan transplant, or provided no information on concomitant immunosuppressants. Data extracted were study design, sample size, immunosuppression regimen, type of transplant, and allograft outcomes.

DATA SYNTHESIS

Of 13 studies included, 1 was level I evidence, 3 were level II-2, 6 were level II-3, and 3 were level III evidence. Three focused on tacrolimus-based regimens, whereas 7 included either cyclosporine or tacrolimus. The only prospective, randomized, multicenter trial demonstrated that early taper of mycophenolate dosage to 1 g/day can be utilized without increased risk of rejection, compared with late tapering, but the rejection rate was high (30-40%). Overall, we found conflicting evidence regarding the impact of mycophenolate dose reduction on rejection rate and allograft loss and that discontinuing mycophenolate led to an increased risk of graft loss as high as 8 fold. Allograft survival was lowest in patients with gastrointestinal complications and those in whom mycophenolate was discontinued, compared with patients with neither gastrointestinal complications nor mycophenolate discontinuation.

CONCLUSIONS

Weak evidence suggests that mycophenolate dose modifications, either reduction or discontinuation, may increase rejection rate and graft loss; however, this is more apparent in cyclosporine-based regimens. Prospective, well-designed trials are necessary to definitively determine the impact of dose reduction in renal transplant recipients on tacrolimus-based regimens.

Combination of low-dose mycophenolate mofetil with cyclosporine and methotrexate as GVHD prophylaxis in unrelated donor allogeneic stem cell transplantation

We report the results of HLA-matched unrelated donor allogeneic stem cell transplantation with new GVHD prophylaxis regimen consisted of cyclosporine, methotrexate and low-dose mycophenolate mofetil in 139 patients with hematologic malignancies. The incidence of grades II-IV and III-IV acute GVHD were 43.0% and 17.3%, respectively. The incidence of chronic GVHD was 42.1%, with 16.5% extensive grade. The cumulative incidence of transplant-related mortality at 100 days and 3 years were 7.9% and 29.7%, respectively. Three-year overall survival, disease-free survival and relapse incidence were 58.7%, 55.3% and 19.6%, respectively. These results suggest the new regime may be effective for the prophylaxis of acute and chronic GVHD in unrelated donor transplantation.

Reasons for dose reduction of mycophenolate mofetil during the first year after renal transplantation and its impact on graft outcome

Mycophenolate mofetil (MMF) decreases the risk of acute rejection and is associated with improved graft survival in renal transplant recipients. However, MMF-related side effects often necessitate dose reduction, which may expose patients to a higher risk of acute rejection and graft loss. This study's aim was to examine the reasons for MMF dose reduction during the first post-transplant year and its impact on acute rejection, overall and death-censored graft loss.

METHODS

Single-center retrospective analysis of 749 renal transplant recipients treated with MMF in their initial maintenance immunosuppressive protocol.

RESULTS

In 365 patients (48.7%) a total of 530 MMF dose reductions were done. Reasons for reduction were hematologic toxicity (46.5%), infection (16.1%), gastrointestinal side effects (12.3%), malignancy (2.1%), study protocol (14.6%), and unknown (13.5%). MMF dose reduction as such was not an independent predictor of acute rejection or graft survival, although reductions in ≥ 50% of initial dose were significantly associated with acute rejection.

CONCLUSIONS

In this retrospective cohort, by far the most important reason for MMF dose reduction during the first post-transplantation year was hematologic. MMF dose reductions in ≥ 50% increased the risk of acute rejection but did not compromise graft survival.

Combination of CsA, MTX and low-dose, short-course mycophenolate mofetil for GVHD prophylaxis

In an effort to reduce the incidence and severity of acute GVHD (aGVHD), we have developed a new prophylaxis regimen combining cyclosporine and MTX with a short 30-day course of low-dose (500 mg per day) mycophenolate mofetil. This regimen was studied prospectively 100 patients undergoing HLA-matched and 1-antigen-mismatched allogeneic peripheral blood SCT from related donors. The cumulative incidence of aGVHD was 16% (grades II-IV (9.5%) and grades III-IV (1%)). The cumulative incidence of chronic GVHD (cGVHD) was 53% with 28% extensive cGVHD. The cumulative incidence of transplant-related mortality at 100 days and 3 years were 6 and 13%. The estimated probabilities of disease-free survival at 3 years in standard- and high-risk patients were 77 and 30%, respectively (P<0.0001). The estimated probabilities of overall survival at 3 years in standard- and high-risk patients were 77 and 37%, respectively (P<0.0001). These data show a substantial decrease in the risk of developing aGVHD without an increase in relapse or any adverse impact on survival in standard-risk patients.