Aplastic anemia is a relatively uncommon disease and conventional management options include immunosuppressive drugs and/or haematopoeitic stem cell transplantation. It is now known that the pathogenesis of aplastic anemia is immune mediated. Mycophenolate mofetil is a common immunosuppressive drug now used mainly in prophylaxis of graft rejection in organ transplant and also for prevention/treatment for graft versus host disease in haemtopoeitic stem cell transplantation. It is thought that mycophenolate mofetil may be useful in this group of patients. In this short report, mycophenolate mofetil was tried in 6 patients who had severe aplastic anemia with variable doses for a minimum duration of 9 months. The result has however not been encouraging.
A 20-year-old girl first notice bilateral ocular muscle weakness in 2001. Two months later, she developed acute muscle paralysis and respiratory failure which required ventilation. Serum anti-acetylcholine receptor antibodies and repetitive nerve stimulation test was positive and consistent with myasthenia gravis (MG). CT scan thorax revealed thymic enlargement and she underwent a video assisted thymectomy (VATS). However, over the next three years, despite maximal doses of various immunosuppressive agents with plasmapheresis and intravenous immunoglobulin, she was admitted with recurrent myasthenic crisis without any obvious precipitant. She was then commenced on mycophenolate mofetil and together with regular plasmapheresis, cyclosporine and prednisolone, her symptoms have finally improved and brought under control.
Drug-induced acute interstitial nephritis is a well-recognised and important reversible cause of acute renal failure. Peroxisome-proliferator activated receptor-gamma agonists, such as rosiglitazone, have been proven to be safe in chronic kidney disease patients. We describe a 65-year-old man with long-standing diabetes mellitus and hypertension, presenting with a five-day history of fluid overload and uraemic symptoms. There was no ingestion of analgesics, alternative medicine and other nephrotoxic drugs, the only new prescription being rosiglitazone, which was commenced during his last clinic follow-up two weeks prior to presentation. He required haemodialysis with minimal improvement in renal profile, despite cessation of the offending drug. Renal biopsy revealed findings consistent with acute interstitial nephritis. An episode of upper gastrointestinal bleeding with bleeding duodenal ulcer limited the use of steroids. He was treated with a course of mycophenolate mofetil which showed good gradual response and he remained stable with residual renal impairment.
Mycophenolate is an immunosuppressive agent which has been used in systemic lupus erythematosus (SLE) patients who have failed conventional therapy. However, the use of mycophenolate sodium in extra-renal SLE involvement has yet to be established. This study aimed to assess the efficacy of mycophenolate sodium in extra-renal SLE.
BACKGROUND: The aim of the present study was to evaluate the efficacy of mycophenolate mofetil in the induction therapy of proliferative lupus nephritis.
METHODS: Forty-four patients from eight centres with newly diagnosed lupus nephritis World Health Organization class III or IV were randomly assigned to either mycophenolate mofetil (MMF) 2 g/day for 6 months or intravenous cyclophosphamide (IVC) 0.75-1 g/m(2) monthly for 6 months in addition to corticosteroids.
RESULTS: Remission occurred in 13 out of 25 patients (52%) in the IVC group and 11 out of 19 patients (58%) in the MMF group (P = 0.70). There were 12% in the IVC group and 26% in the MMF group that achieved complete remission (P = 0.22). Improvements in haemoglobin, the erythrocyte sedimentation rate, serum albumin, serum complement, proteinuria, urinary activity, renal function and the Systemic Lupus Erythematosus Disease Activity Index score were similar in both groups. Twenty-four follow-up renal biopsies at the end of therapy showed a significant reduction in the activity score in both groups. The chronicity index increased in both groups but was only significant in the IVC group. Adverse events were similar. Major infections occurred in three patients in each group. There was no difference in gastrointestinal side-effects.
CONCLUSIONS: MMF in combination with corticosteroids is an effective induction therapy for moderately severe proliferative lupus nephritis.
BACKGROUND AND OBJECTIVE: Mycophenolic acid (MPA) provides effective treatment for lupus nephritis patients. Owing to its large pharmacokinetic variability, it is questionable whether standard fixed dose therapy can achieve optimal MPA exposure. The aim of this study was to develop a population pharmacokinetic model of MPA and its metabolite, 7-O-MPA-β-glucuronide (MPAG), to identify important covariate influences and better predict patient dosing requirements.
METHODS: MPA and MPAG concentration-time profiles were collected from 25 patients receiving mycophenolate mofetil (MMF) with or without cyclosporine (CsA) co-therapy. Samples were collected pre-dose and at 1, 2, 4, 6 and 8 h post-dose on one or two occasions.
RESULTS: A total of 225 and 226 concentration-time measurements of MPA and MPAG, respectively, were used to develop the model, utilizing NONMEM® software. A two-compartment model with first-order absorption and elimination for MPA and a one-compartment model with first-order elimination and enterohepatic circulation (EHC) for MPAG best described the data. Apparent clearance of MPAG (CL/F MPAG) significantly decreased with reducing renal function and extent of EHC was reduced with concomitant CsA use. Simulations using the final model showed that a 70-kg subject with a creatinine clearance of 90 mL/min receiving concomitant CsA would require 1.25 g of MMF twice daily while a similar subject who did not receive concomitant CsA would require 0.75 g twice daily to achieve a MPA area under the concentration-time curve from 0 to 12 h (AUC0-12) of 45 mg·h/L.
CONCLUSION: A 'tiered' dosing approach considering patient renal function and CsA co-therapy, rather than a 'one dose fits all' approach, would help individualize MMF therapy in adult lupus nephritis patients to ensure more patients have optimal MPA exposure.
Study site: Nephrology and Systemic Lupus Erythematosus (SLE) Clinics, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia