Cost effectiveness of rituximab and mycophenolate mofetil for neuromyelitis optica spectrum disorder in Thailand: Economic evaluation and budget impact analysis

Neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory condition of the central nervous system. The extent of disability depends on the severity of the disease and the number of relapses. Although azathioprine is currently the main treatment for patients with NMOSD in Thailand, patients often relapse during its use. Hence, it is argued that there are other drugs that would be more effective. The purpose of this study is to evaluate, from a societal perspective and from the economic impact on Thailand’s healthcare system, the cost utility of treatment with mycophenolate mofetil (MMF) and rituximab in patients resistant to azathioprine. The Markov model with a one-year cycle length was applied to predict the health and cost outcomes in patients with NMOSD over a lifetime. The results showed that rituximab exhibited the highest quality-adjusted life year (QALY) gains among all the options. Among the rituximab-based treatments, the administration of a rituximab biosimilar with CD27⁺ memory B cell monitoring proved to be the most cost-effective option. At the willingness-to-pay threshold of 160,000 Thai baht (THB), or 5,289 US dollar (USD), per QALY gained, the treatment exhibited the highest probability of being cost effective (48%). A sensitivity analysis based on the adjusted price of a generic MMF determined that the treatment was cost effective, exhibiting an incremental cost-effectiveness ratio of -164,653 THB (-5,443 USD) and a 32% probability of being cost effective. The calculated budget impact of treating patients resistant to conventional therapy was 1–6 million THB (33,000–198,000 USD) for the first three years, while after the third year, the budget impact stabilized at 3–4 million THB (99,000–132,000 USD). These data indicate that, in Thailand, treatment of drug resistant NMOSD with a rituximab biosimilar with CD27⁺ memory B cell monitoring or treatment with a generic MMF would be cost effective and would result in a low budget impact. Therefore, the inclusion of both the rituximab biosimilar and a generic MMF in the National Drug List of Essential Medicine for the treatment of NMOSD may be appropriate.

Cost-effectiveness of modern mTOR inhibitor based immunosuppression compared to the standard of care after renal transplantation in Germany

OBJECTIVES

Standards of immunosuppression in renal transplantation have changed dynamically in recent years. We here provide a refined advanced pharmacoeconomic model which uses state-of-the-art methods including a mixed treatment comparison (MTC) analysis. The aim was to assess the cost-effectiveness of current immunosuppressive therapy regimens (TR): "sirolimus + early withdrawal of cyclosporine + steroids" (TR1), "sirolimus-early transition" (TR2), "everolimus-early transition" (TR3) and "tacrolimus low dose + mycophenolate mofetil (MMF) + steroids" (TR4).

METHODS

An up-to-date Markov model with current source data was employed to assess the cost-effectiveness of modern immunosuppressive regimens over 12-month and 10-year time periods. Transition probabilities for the occurrence of events for the first year were based on an MTC analysis. The robustness of the model was tested in extensive sensitivity analyses.

RESULTS

Within the 12-month time period TR2 yields the highest life years (0.987 LY), generating costs of 17,500 <euro>. In terms of years with functioning graft (FG), TR4 yields the best efficacy over the 12-month model duration (0.970 years with FG). For the 10-year time period, TR2 yields the lowest costs (107,246 <euro>) and dominates both TR3 and TR1, as it is simultaneously more effective. Within the 10-year model duration, TR4 reaches slightly higher effects compared with TR2 (6.493 vs. 6.474 LY) resulting in an incremental cost-effectiveness ratio of 387,684 <euro> per LY gained.

CONCLUSIONS

The early transition to sirolimus provides long-term efficiency results comparable with a tacrolimus-based regimen, which represents a common treatment standard after kidney transplantation. Both are superior to other investigated immunosuppressive regimens.

Low-dose RATG with or without basiliximab in renal transplantation: a matched-cohort observational study

BACKGROUND/AIMS

In renal transplantation, peri-operative low-dose rabbit-antithymocyte-globulin (RATG) plus basiliximab induction prevented acute allograft rejection more effectively than post-operative RATG plus basiliximab induction. We investigated the specific antirejection contribution of basiliximab in this context.

METHODS

This single-center, observational, matched-cohort study evaluated allograft rejections (primary outcome), steroid exposure and side effects, GFR (iohexol plasma clearance) and treatment costs in 16 deceased-donor renal transplant recipients induced with RATG (0.5 mg/kg/day) and 32 age-, gender- and treatment-matched reference-patients given RATG plus basiliximab (20 mg on days 0 and 4).

RESULTS

Induction was well tolerated. At 18 months, 8 patients (50%) vs. 3 reference-patients (9.4%) rejected the graft [HR (95% CI): 6.53 (1.73-24.70), p = 0.006]. Difference was significant (p < 0.01) even after adjusting for recipient/donor age and gender, cold ischemia time and HLA mismatches. There were 1 antibody-mediated rejection and 2 moderate cellular rejections in patients vs. none in reference-patients (p = 0.032). The median (interquartile range) prednisone cumulative dose was remarkably higher in patients than reference-patients [4.78 (1.12-6.10) vs. 0.19 (0.18-3.81) grams, p = 0.002]. Three patients vs. 24 reference-patients were off-steroid at study end (p < 0.001). Three patients vs. no reference-patient developed new-onset diabetes (p = 0.003). Both inductions similarly depleted B-cells. Outcomes of AZA- vs. MMF-treated participants were similar. GFR was similar in all groups. Compared to MMF, AZA therapy saved ≈ EUR 2,500/year and by month 14.3 post-transplant compensated basiliximab costs.

CONCLUSION

In renal transplantation, basiliximab plus peri-operative low-dose RATG more efficiently prevented allograft rejection than RATG monotherapy, and minimized steroid exposure and toxicity. AZA- vs MMF-based maintenance immunosuppression largely compensated the extra costs of basiliximab.

Economic impact and long-term graft outcomes of mycophenolate mofetil dosage modifications following gastrointestinal complications in renal transplant recipients

INTRODUCTION

Gastrointestinal (GI) complications are common following renal transplantation. Discontinuing or reducing the dosage of mycophenolate mofetil can improve GI tolerability but adversely affect graft outcomes. This analysis was undertaken to assess the 3-year economic and clinical impact of mycophenolate mofetil dosage modifications or discontinuation following post-transplant GI events compared with no dosage modification.

METHODS

Adult renal transplant recipients with a Medicare-covered mycophenolate mofetil prescription at the time of GI complication between 1995 and 2000 were drawn from the US Renal Data System (USRDS). The 3-year graft survival rates after first diagnosis of a GI complication were obtained in four cohorts of patients according to mycophenolate mofetil administration within 6 months of initial GI diagnosis: (i) no dosage change in mycophenolate mofetil (NC); (ii) one or more episodes of mycophenolate mofetil dosage reduction <50% of the initial dosage, lasting >30 days (DR <50%); (iii) one or more episodes of mycophenolate mofetil dosage reduction >or=50% of the initial dosage, lasting >30 days (DR >or=50%); and (iv) one or more episodes of mycophenolate mofetil discontinuation >30 days (DC).Two multivariate models were used to estimate the association between DR and DC and graft survival <6 months after GI diagnosis and 6-36 months after diagnosis. In each cohort, Medicare costs for maintaining a patient with stable function were calculated using regression and were augmented with cost of graft failure, resumed maintenance dialysis and death post-graft loss using Medicare data supplied by the USRDS. Survival and cost outcomes were integrated in a 3-year Markov model with 6-month cycles. The perspective was that of Medicare, and costs and outcomes were discounted by 3% per annum.

RESULTS

Adult patients (n = 3589) with a mycophenolate mofetil prescription at time of diagnosis of GI event were identified: NC = 2230 (62.1%); DR <50% = 247 (6.9%); DR >or=50% = 348 (9.7%); and DC = 764 (21.3%). In the first 6 months after GI diagnosis, DC was associated with increased risk of graft failure (hazard ratio [HR] 3.20; 95% CI 1.71, 5.99; p < 0.0001). During the period 6-36 months after GI diagnosis, the HR for graft loss was higher for the DR >or=50% group (HR 1.32; 95% CI 1.02, 1.70; p < 0.05) and DC group (HR 1.35; 95% CI 1.09, 1.69; p < 0.01) relative to the NC group.Expected 3-year cumulative Medicare costs per patient were USD 68,495 for the NC and DR <50% groups, USD 70,886 for the DR >or=50% group, USD 79,015 for the DC group and USD 70,967 overall. Respective QALYs were 2.32, 2.30, 2.27 and 2.31. In sensitivity analysis, reducing the rate of DR and DC by 25% would have lowered expected costs by USD 2.2 million in the study population and increased QALYs by 11.2. Monte Carlo simulation indicated a 93% probability that such reduction in the relative risk of mycophenolate mofetil DR/DC was cost saving or cost neutral.

CONCLUSION

Dosage reduction or discontinuation of mycophenolate mofetil in the first 6 months after diagnosis of GI complications is associated with significantly increased risk of graft failure and increased healthcare costs in adult renal transplant recipients.

Red blood cell anemia in a patient with pemphigus vulgaris induced by the use of mycophenolate mofetil and prednisone

Mycophenolate mofetil (MMF) is an immunosuppressive drug used in renal transplantation, lupus nephritis and pemphigus vulgaris patients. An apparent link is described between the use of MMF with prednisone to treat pemphigus vulgaris and the development of red blood cell anemia. Specifically, after initiation of 500 mg MMF twice a day given in conjunction with the long-standing use of prednisone, which had been tapered to a dose of 10 mg daily, the patient's red blood cell count dropped by 17% over 7 weeks. To put this into perspective, total aplasia of red blood cells for 40 days would result in a drop of 30-33% in the red blood cell count. In the transplantation literature, MMF has been noted to lower red blood cell counts. One previous study of four transplant patients whose immediate post-transplantation immunosuppression utilized corticosteroids, cyclosporine, MMF, and anti-T-lymphocyte globulin noted anemia in 13% of them. The dermatology literature heretofore has not noted that anemia is a side effect of patients taking MMF to treat pemphigus. This report suggests that anemia can occur due to MMF, in particular when it is given with prednisone, a side effect well documented in the transplantation literature when the triple combination of MMF, cyclosporine and prednisone is used. It would therefore seem prudent to monitor red and white blood cell counts in patients taking MMF. A review of the literature also reveals that MMF is a safe medication that appears to have a more favorable side effect profile than azathioprine, although it is more expensive than azathioprine.

The cost-effectiveness of mycophenolate mofetil as firstline therapy in active lupus nephritis

OBJECTIVES

Systemic lupus erythematosus (SLE) is an autoimmune disorder that can affect any system of the body. Involvement of the kidneys, lupus nephritis (LN), affects up to 50% of SLE patients during the course of their disease, and is characterized by periods of active disease (flares) and remission. For more severe nephritis, an induction course of immunosuppressive therapy is recommended. Options include intravenous cyclophosphamide (IVC) or mycophenolate mofetil (MMF), followed by a maintenance course, typically of azathioprine. The objective of this study is to determine which therapy results in better quality of life (QoL) for patients and which represents best value for money for finite health service resources.

METHODS

A patient-level simulation model is developed to estimate the costs and quality-adjusted life-years (QALYs) of a patient treated with IVC or MMF for an induction period of six months. Efficacy, QoL, resource use and cost data are extracted from the literature and standard databases and supplemented with expert opinion where necessary.

RESULTS

On average, the model predicts MMF to result in improved QoL compared with IVC. MMF is also less expensive than IVC, costing pound 1600 (euro 2400; US$ 3100) less over the period, based on 2005 NHS prices. The major determinant and cost driver of this result is the requirement for a day-case procedure to administer IVC. Sensitivity analysis shows an 81% probability that MMF will be cost-effective compared with IVC at a willingness to pay of pound 30,000 (euro 44,700; US$ 58,500) per QALY gained.

CONCLUSION

MMF is likely to result in better QoL and be less expensive than IVC as induction therapy for LN.

Does mycophenolate mofetil decrease the recurrent acute rejection in renal transplant recipients

PURPOSE

Mycophenolate mofetil (MMF) has emerged as a valuable immunosuppression in renal transplant patients. However, it is expensive and cannot be used routinely in our population.

MATERIAL AND METHODS

In a retrospective study, 60 renal transplant patients on MMF based triple immunosuppression were analysed. The indication for MMF was as rescue therapy after treatment of acute vascular rejection (Banff type-4, grade IIA, IIB and III) in all patients. However, 20 such patients also had associated chronic liver diseases. The patients were given 1.5-2.0 g MMF in two divided doses at least for 6 months, depending upon the tolerability, adverse effects and affordability, and followed-up at least for 1 year. The control group consisted of 60 cases of acute vascular rejection (Banff type-4, grade IIA, IIB and III) who were placed on cyclosporine, azathioprine and steroid based maintenance immunosuppressive regimen in same time frame.

RESULTS

The incidence recurrent acute rejections in MMF group was 18% and 42% in control group (P < 0.005). The serum transaminases in all patients of the liver diseases became normal in 3-6 months. The incidence of opportunistic infections in MMF and control group were 22% and 11% respectively (P < 0.05). The MMF based regimen was two times more expensive. The 1 year patient and graft survivals between two groups were not statistically significantly different.

CONCLUSION

The MMF based regimen significantly decreases the recurrent acute rejections. However, it is expensive and cannot be used routinely in all patients in Indian scenario.

Clinical and cost-effectiveness of newer immunosuppressive regimens in renal transplantation: a systematic review and modelling study

OBJECTIVES

To examine the clinical effectiveness and cost-effectiveness of the newer immunosuppressive drugs for renal transplantation: basiliximab, daclizumab, tacrolimus, mycophenolate (mofetil and sodium) and sirolimus.

DATA SOURCES

Electronic databases. Industry submissions. Current Clinical Trials register. Cochrane Collaboration Renal Disease Group.

REVIEW METHODS

The review followed the InterTASC standards. Each of the five company submissions to the National Institute for Clinical Excellence (NICE) contained cost-effectiveness models, which were evaluated by using a critique covering (1) model checking, (2) a detailed model description and (3) model rerunning.

RESULTS

For induction therapy, three randomised controlled trials (RCTs) found that daclizumab significantly reduced the incidence of biopsy-confirmed acute rejection and patient survival at 6 months/1 year compared with placebo, but not compared with the monoclonal antibody OKT3. There was no significant gain in patient survival or graft loss at 3 years. The incidence of side-effects with daclizumab reduced compared to OKT3. Eight RCTs found that basiliximab significantly improved 6-month/1-year biopsy-confirmed acute rejection compared to placebo, but not compared to either ATG or OKT3. There was no significant gain in either 1-year patient survival or graft loss. The incidence of side-effects with basiliximab was not significantly different compared to OKT3/ATG. For initial/maintenance therapy, 13 RCTs found that tacrolimus reduced the 6-month/1-year incidence of biopsy-proven acute rejection compared to ciclosporin. There was no significant improvement in either 1-year or long-term (up to 5 years) graft loss or patient survival. The acute rejection benefit of tacrolimus over ciclosporin appeared to be equivalent for Sandimmun and Neoral. There were important differences in the side-effect profile of tacrolimus and ciclosporin. Seven RCTs found that mycophenolate mofetil (MMF) reduced the incidence of acute rejection. There was no significant difference in patient survival or graft loss at 1-year or 3-year follow-up. There appeared to be differences in the side-effect profiles of MMF and azathioprine (AZA). No RCTs comparing MMF with AZA were identified. One RCT compared mycophenolate sodium (MPS) to MMF and reported no difference between the two drugs in 1-year acute rejection rate, graft survival, patient survival or side-effect profile. Two RCTs suggest that addition of sirolimus to a ciclosporin-based initial/maintenance therapy reduces 1-year acute rejections in comparison to a ciclosporin (Neoral) dual therapy alone and substituting azathioprine with sirolimus in initial/maintenance therapy reduces the incidence of acute rejection. Graft and patient survival were not significantly different with either sirolimus regimen. Adding sirolimus increases the incidence of side-effects. The side-effect profiles of azathioprine and sirolimus appear to be different. For the treatment of acute rejection, three RCTs suggested that both tacrolimus and MMF reduce the incidence of subsequent acute rejection and the need for additional drug therapy. Only one RCT and one subgroup analysis in children (<18 years) were identified comparing ciclosporin to tacrolimus and sirolimus, respectively.

CONCLUSIONS

The newer immunosuppressant drugs (basiliximab, daclizumab, tacrolimus and MMF) consistently reduced the incidence of short-term (1-year) acute rejection compared with conventional immunosuppressive therapy. The independent use of basiliximab, daclizumab, tacrolimus and MMF was associated with a similar absolute reduction in 1-year acute rejection rate (approximately 15%). However, the effects of these drugs did not appear to be additive (e.g. benefit of tacrolimus with adjuvant MMF was 5% reduction in acute rejection rate compared with 15% reduction with adjuvant AZA). Thus, the addition of one of these drugs to a baseline immunosuppressant regimen was likely to affect adversely the incremental cost-effectiveness of the addition of another. The trials did not assess how the improvement in short-term outcomes (e.g. acute rejection rate or measures of graft function), together with the side-effect profile associated with each drug, translated into changes in patient-related quality of life. Moreover, given the relatively short duration of trials, the impact of the newer immunosuppressants on long-term graft loss and patient survival remains uncertain. The absence of both long-term outcome and quality of life from trial data makes assessment of the clinical and cost-effectiveness on the newer immunosuppressants contingent on modelling based on extrapolations from short-term trial outcomes. The choice of the most appropriate short-term outcome (e.g. acute rejection rate or measures of graft function) for such modelling remains a matter of clinical and scientific debate. The decision to use acute rejection in the meta-model in this report was based on the findings of a systematic review of the literature of predictors of long-term graft outcome. Only a very small proportion of the RCTs identified in this review assessed patient-focused outcomes such as quality of life. Since immunosuppressive drugs have both clinical benefits and specific side-effects, the balance of these harms and benefits could best be quantified through future trials using quality of life measures. The design of future trials should be considered with a view to the impact of drugs on particular renal transplant groups, particularly higher risk individuals and children. Finally, there is a need for improved reporting of methodological details of future trials, such as the method of randomisation and allocation concealment. A number of issues exist around registry data, for example the use of multiple drug regimens and the need to assess the long-term outcomes. An option is the use of observational registry data including, if possible, prospective data on all consecutive UK renal transplant patients. Data capture for each patient should include immunosuppressant regimens, clinical and patient-related outcomes and patient demographics.

Effect of New Immunosuppressive Regimens on Cost of Renal Transplant Maintenance Immunosuppression

Although newer immunosuppressive drugs control acute rejection better and have short-term economic advantages, their long-term cost-effectiveness is unknown. We studied the frequency with which different maintenance immunosuppression regimens were used in 3 renal transplantation cohorts treated in 1990, 1994, and 1998 (total number, 3279). We calculated the mean annual immunosuppressive costs based on the true costs in a medium-sized hospital. Cyclosporine, with or without azathioprine, was used almost exclusively as the initial maintenance immunosuppressive therapy in 1990-1994. In 1998, 65% of patients received mycophenolate mofetil (MMF), and 20% received tacrolimus (Tac). A growing number of patients from 1990-1994 were converted to MMF (12%-17%) and Tac (4%-8%), while treatment of those from the 1998 cohort remained stable. According to year 2000 costs, the mean immunosuppressive cost at 1 year in 1998 (5380 euros) was almost twice that of 1994 (2902 euros) or 1990 (2855 euros). In these 2 groups the mean cost was stable until 1996, then increased faster in the 1994 cohort (24.8%) than in the 1990 cohort (17.3%), although it remained significantly lower than that in 1998. Correction of the evolution of drug prices and the purchasing value of the peseta greatly absorbed these changes. The MMF and Tac regimens showed greater mean graft life, but without reaching statistical significance in a multivariate study. The introduction of new immunosuppressive drugs has had an important economic effect since 1996; its cost-effectiveness is still pending confirmation in Spain.

The use of mycophenolate mofetil in liver transplant recipients

Mycophenolate mofetil is an important drug in the modern immunosuppressive arsenal. Mycophenolate mofetil is the semisynthetic morpholinoethyl ester of mycophenolate acid. Mycophenolate acid prevents T and B cell proliferation by specifically inhibiting a purine pathway required for lymphocyte division. This paper extensively reviews the experience of mycophenolate mofetil use in liver transplant recipients. In randomised trials, mycophenolate mofetil decreased the rate of acute rejection after liver transplantation, without a significant increase of septic complications. However, so far, there are no data indicating that mycophenolate mofetil increases liver transplant patient or graft survivals. Mycophenolate mofetil is interesting because of its particular side effects profile, which is very different from the other immunosuppressants. The absence of mycophenolate mofetil nephrotoxicity is of specific interest in liver recipients with impairment of renal function. The monitoring of mycophenolate acid area under the concentration time curve might be interesting to limit side effects and provide better clinical efficacy but the exact role of mycophenolate acid monitoring in liver recipients has yet to be further evaluated in large series.

Economic evaluation of everolimus versus mycophenolate mofetil in combination with cyclosporine and prednisolone in de novo renal transplant recipients

An economic evaluation was undertaken alongside a multicentre, international, trial of everolimus (Certican). Resource usage within the trial was assessed, and the cost implications of the use of everolimus were evaluated. Recipients of a primary cadaveric kidney transplant were recruited into a double-blind trial and received either everolimus 1.5 mg (n=194); everolimus 3 mg (n=198) or mycophenolate mofetil (MMF) 2 g (n=196). Clinical outcomes and resource usage were monitored for 12 months following transplantation. Local costs were obtained, and global analysis using health sector PPP rates was undertaken. The mean overall cost of treatment was 33,715 dollars (95%CI 30,013 dollars-37,417 dollars) with everolimus 1.5 mg, 38,519 dollars (95%CI 34,094 dollars-42,943 dollars) with everolimus 3 mg and 36,509 dollars (95%CI 32,430 dollars-40,587 dollars) with MMF. Differences between the three groups did not reach statistical significance. In conclusion, the economic analysis showed statistical equivalence over the three arms of the trial. Further work is required to demonstrate the cost consequences of the use of everolimus compared with MMF in renal transplantation patients.

Enteric-coated mycophenolate sodium: safe conversion from mycophenolate mofetil in maintenance renal transplant recipients

Mycophenolate mofetil (MMF), in combination with cyclosporine and corticosteroids, improves long-term graft function and survival in renal transplant recipients. However, optimal MMF therapy may be limited by gastrointestinal (GI) intolerance, which may result in the need for MMF dose reduction, interruption, or discontinuation, leading to increased risk of acute rejection. Enteric-coated mycophenolate sodium (EC-MPS) is an advanced formulation delivering mycophenolic acid (MPA), developed with the objective of improving MPA-related upper GI adverse events. A pivotal, 12-month, phase III, randomized, multicenter, double-blind, double-dummy, parallel group study investigated whether stable renal transplant patients can be converted from MMF to EC-MPS therapy without compromising tolerability or efficacy. Stable renal transplant recipients received either MMF, 1000 mg b.i.d. (n=159), or EC-MPS, 720 mg b.i.d. (n=163), for 12 months. The incidence of GI adverse events was comparable between both treatment groups at 3 and 6 months, but there was a trend toward reduced severity of GI side effects in the EC-MPS group. There were fewer serious adverse events with EC-MPS and significantly fewer serious infections (P<.05). This comparable safety profile for EC-MPS and MMF also extended to elderly patients and patients with diabetes at baseline. For the composite efficacy variable of biopsy-proven acute rejection, graft loss, death, or loss to follow-up, EC-MPS had a lower 12-month efficacy failure rate (EC-MPS: 7.5% vs MMF: 12.3%; P=ns). These data demonstrate that stable renal transplant recipients receiving MMF can be converted to EC-MPS with no efficacy or tolerability compromise.

Mycophenolate mofetil: a pharmacoeconomic review of its use in solid organ transplantation

Most pharmacoeconomic studies of mycophenolate mofetil have focused on its use as part of maintenance immunosuppression for renal transplantation, involving short-term (3 to 12 months) time frames. In general, mycophenolate mofetil reduced the treatment costs for rejection episodes and graft failure which offset its higher drug acquisition cost compared with azathioprine. Several cost analyses have been modelled on the large multicentre trials of adult renal transplant recipients. The use of mycophenolate mofetil was associated with either cost savings or no additional costs after 6 or 12 months in French, US and Canadian analyses of triple or quadruple immunosuppressant therapy. A further cost analysis utilising a registry database of renal transplant recipients in the US found mycophenolate mofetil to be cost saving compared with azathioprine after 6.4 years when evaluating costs due to graft loss only. Of the limited cost-effectiveness analyses with the drug, one US study modelled the 1- and 10-year cost effectiveness of mycophenolate mofetil and various other immunosuppressants used in combined regimens. Long-term use of mycophenolate mofetil was less cost effective than other regimens, but the use of long-term mycophenolate mofetil in high-risk patients was shown to be a relatively cost-effective strategy. In another US analysis comparing mycophenolate mofetil with azathioprine as part of quadruple therapy, mycophenolate mofetil was associated with slightly lower costs during the first year after renal transplantation as well as improved clinical outcomes.

CONCLUSION

Pharmacoeconomic studies support the use of mycophenolate mofetil as part of immunosuppressant therapy in renal transplantation, at least in the short term. Although the cost effectiveness of mycophenolate mofetil in the long term is less clear, limited pharmacoeconomic data available appear promising. Among issues to be examined in future economic analyses in renal transplantation are the calcineurin-sparing potential of mycophenolate mofetil and the feasibility of using more efficient mycophenolate mofetil dosage regimens when using the drug on a long-term basis. Additional pharmacoeconomic analyses of mycophenolate mofetil are also needed in other types of solid organ transplantation.

Mycophenolate mofetil: suggested guidelines for use in kidney transplantation

Mycophenolate mofetil (MMF) is an immunosuppressive drug designed to inhibit inosine monophosphate dehydrogenase (IMPDH). IMPDH is a key enzyme in the de novo purine synthesis of lymphocytes. It is crucially important for proliferative responses of human T and B lymphocytes. The inhibition of IMPDH thus leads to selective lymphocyte suppression. After successful use in various in vitro and animal models, MMF was brought to clinical trial in patients undergoing transplantation. The drug is rapidly and completely absorbed following oral administration. Pilot studies of administration with cyclosporin and corticosteroids suggested a significant reduction in the incidence of organ rejection at dosages of 1 to 3 g/day. As a result of these studies, 3 pivotal randomised double-blind multicentre trials, involving nearly 1500 patients, were designed to investigate the effects of addition of MMF to different standard immunosuppressive protocols on the prevention of acute renal allograft rejection. After 6 months, the rates of biopsy-proven rejection were significantly reduced in patients receiving MMF. In combination with cyclosporin and corticosteroids, the adverse effect profile resembled that of azathioprine. Most adverse effects were associated with the gastrointestinal tract, the blood system and opportunistic infections. MMF offers improved immunosuppressive therapy following renal and probably other solid organ transplantation. MMF has been licensed since 1995 for the prevention of acute renal allograft rejection in most countries. It has been used in different combinations of immunosuppressive drugs and in various dosages and regimens.

Mycophenolate mofetil--is it worth the cost? The in-favor opinion

Since its introduction, mycophenolate mofetil (MMF) has rapidly gained acceptance among renal transplant physicians. Three large multicenter studies have shown that MMF decreased the incidence of acute rejection episodes by 50%. While clinical data supporting the long-term benefits of MMF are not available, there is some experimental evidence which demonstrates that MMF may play a role in the prevention of chronic allograft rejection. Furthermore, MM F is a potent immunosuppressive agent, which could result in a reduction of the dose of cyclosporin A (CsA) required and subsequently reduce its associated toxicity. Despite the fact that MMF is six to seven times more expensive than azathioprine (AZA), its introduction into maintenance immunosuppressive protocols may not increase renal transplant charges during the first year after renal transplant as its cost can be offset by the reduced number of acute rejection episodes (ARE). The long-term societal impact of MMF will need to be evaluated as the data related to graft and patient survival, as well as chronic rejection, become available.

Reduced kidney transplant rejection rate and pharmacoeconomic advantage of mycophenolate mofetil

BACKGROUND

Several multinational controlled clinical trials have shown that triple therapy immunosuppressive regimens which include mycophenolate mofetil (MMF), cyclosporin A (CSA) and steroids (S) are superior compared with conventional regimens which include azathioprine (AZA), CSA and S, mainly because MMF reduces the rate of acute rejection episodes in the first 6 months after kidney transplantation. Post-marketing studies are useful to evaluate the general applicability and costs of MMF-based immunosuppressive regimens.

METHODS

Based on the excellent results of the published controlled clinical trials, we have changed the standard triple therapy immunosuppressive protocol (AZA+CSA+S) to an MMF-based regimen (MMF+CSA+S) at our centre. To analyse the impact of this change in regimen, we have monitored 6-month patient and graft survival, rejection rate, serum creatinine and CSA levels, as well as the costs of the immunosuppressive and anti-rejection treatments, in 40 consecutive renal transplant recipients (MMF group) and have compared the data with 40 consecutive patients transplanted immediately prior to the change in regimen (AZA group).

RESULTS

Recipient and donor characteristics were similar in the AZA and MMF groups. Patient survival (37/40; 92.5% in the AZA group vs 38/40; 95% in the MMF group), graft survival (36/40 vs 36/40; both 90%) and serum creatinine (137+/-56 vs 139+/-44 micromol/l) after 6 months were not significantly different. However, the rate of acute rejection episodes (defined as a rise in creatinine without other obvious cause and treated at least with pulse steroids) was significantly reduced with MMF from 60 to 20% (P=0.0005). The resulting cost for rejection treatment was lowered 8-fold (from sFr. 2113 to 259 averaged per patient) and the number of transplant biopsies was lowered > 3-fold in the MMF group. The cost for the immunosuppressive therapy was increased 1.5-fold with MMF (from sFr. 5906 to 9231 per patient for the first 6 months).

CONCLUSIONS

The change from AZA to MMF resulted in a significant reduction in early rejection episodes, resulting in fewer diagnostic procedures and rehospitalizations. The optimal long-term regimen in terms of patient and pharmacoeconomic benefits remains to be defined.

The cost effectiveness of mycophenolate mofetil in the first year after primary cadaveric transplant. U.S. Renal Transplant Mycophenolate Mofetil Study Group

Mycophenolate mofetil (MMF) has been shown to reduce the incidence of acute graft rejection in three controlled trials of cadaveric renal transplantation. In a U.S. trial using quadruple sequential induction therapy as control, the MMF 2-g treatment group had an acute rejection rate 40.6% lower than control in the first posttransplant year (27.9% MMF-treated versus 47.0% control). The purpose of this analysis is to evaluate the economic implications of these clinical differences. The analysis relies on resource use data from the trial and other sources. Medical costs were estimated using a societal perspective and excluded the cost of the transplant procedure and organ acquisition. The two groups were compared in terms of treatment for acute rejection and opportunistic infection, graft survival, dialysis use, and maintenance immunosuppression. The results suggest that, on average, when compared with standard therapy, patients treated with MMF are likely to have lower rejection-related treatment costs because of a lower incidence of rejection ($6237 versus $3702), lower dialysis and graft failure costs because of improved graft survival ($20,104 versus $16,972), no difference in opportunistic infection treatment costs ($1962 versus $1962), and higher additional immunosuppression costs ($855 versus $5170). Taken together, these results suggest that patients treated with MMF are, on average, likely to have slightly lower first-year costs ($29,158 versus $27,807) compared with control, indicating that MMF treatment is cost-effective in the first year. These results remained stable under sensitivity analyses, with plausible variation in the rates of acute rejection, graft survival, and infection.

[Economic contribution of mofetil mycofenolate as preventive immunosuppressive treatment after renal transplantation from cadaver]

OBJECTIVES

The economic impact resulting from the clinical consequences of immunosuppressive strategy using mycophenolate mofetil in new renal transplant recipients was conducted considering the viewpoint of the health insurance system.

METHODS

The analysis was based on the results of three controlled randomized double-blind clinical trials comparing mycophenolate mofetil with placebo or azathioprine in 1003 out of 1493 included patients respectively. Health care costs associated with each event were determined by 7 French experts in renal transplantation working in six different hospitals. Direct cumulative costs for each strategy were compared.

RESULTS

The studies demonstrated a difference in the incidence of acute rejection and treatment failures whatever the cause. The three trials showed that, compared with current strategies, use of mycophynolate mofetil in the immunosuppression protocol generated a 19 to 38% cost reduction during the 6 months after transplantation. Cost reduction resulted from lower incidence of acute rejection and the subsequent nephrectomics and dialysis sessions. The sensitivity analysis on the most important cost factors-cost of hospitalization per day and number of hospitalization days-confirmed strength of the results.

CONCLUSION

Use of mycophenolate mofetil in the immunosuppressive prophylaxis protocol after renal transplantation allows a reduction in the direct costs during the 6 months following transplantation.

Mycophenolate mofetil in kidney transplantation

Mycophenolate mofetil is a new immunosuppressive agent recently released for clinical use, in conjunction with steroids and cyclosporine, for the prevention of acute rejection in renal transplant patients. It inhibits the enzyme inosine monophosphate dehydrogenase, which is essential for de-novo synthesis of guanine nucleotides. The result is lymphocyte-selective arrest of cell division, with little effect on other tissues. In clinical trials in renal transplant, its efficacy and safety have been established: mycophenolate mofetil reduces acute rejection episodes by approximately 50%, with the principal toxicity being gastrointestinal, and perhaps some increase in cytomegalovirus infection. Overall, mycophenolate mofetil (plus cyclosporine and steroids) has a toxicity profile similar to that of azathioprine but with considerably increased efficacy. Despite its cost, mycophenolate mofetil is likely to be used in many renal transplant centres to reduce acute rejection, especially in the first year. Future trials are necessary to establish its long-term role in renal transplantation and its usefulness in the transplantation of other organs.