Prednisone withdrawal late after adult liver transplantation reduces diabetes, hypertension, and hypercholesterolemia without causing graft loss

Single-agent immunosuppression after liver transplantation: what is possible?

Orthotopic liver transplantation is a life saving and life enhancing procedure. The development of immunosuppressive drugs has contributed to the high rate of success in terms of both patient and graft survival. However, the considerable adverse effects of these therapies are affecting long-term outcomes of transplant recipients. Complications related to immunosuppression are responsible for the majority of deaths in patients surviving more than 1 year. Therefore, the search for an optimal immunosuppressive regimen has become of paramount importance. The liver has proved to be an 'immunologically privileged' organ, capable in several animal models to be accepted as an allograft without any intervention on the immune system of the recipient. In some human liver allografts acceptance of the new organ is recognised after withdrawal of immunosuppressants, but prior identification of such individuals is not yet possible, thus negating this management option. Graft-recipient interaction is peculiar in liver transplantation: acute cellular rejection does not always need to be treated, and if it is not severe, appears to be associated with a better survival of both patient and graft. In the last decade there has been an evolution of immunosuppressive protocols, driven by empirical observation and a deeper understanding of immunological events after transplant. However, most modifications have been made because of the necessity to reduce long-term drug related morbidity and mortality. Withdrawal of corticosteroids has proven to be safely achievable in most patients, with no deleterious effects on patient or graft survival but with a great benefit in terms of reduction of incidence of metabolic and cardiovascular complications. Long-term 'steroid-free' regimens are therefore now widely used. Patients with stable graft function can be easily maintained using a single drug usually after 6 or 12 months and usually with a calcineurin inhibitor. The more evolved step of using monotherapy ab initio has also proven to be effective in a few studies and needs to be explored further. In the future new strategies will be designed to help the development of tolerance of the allograft, selectively stimulating instead of suppressing the immune reaction of the recipient.

Can the potential benefits of statins in general medical practice be extrapolated to liver transplantation?

Hypercholesterolemia is a common complication of liver transplantation and is a risk factor for cardiovascular disease after renal and heart transplant. The effect of hyperlipidemia after liver transplantation is less certain, but a less favorable outcome is to be expected. 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors or statins have proven efficacy in reducing serum cholesterol and mortality from cardiovascular disease in the general population. Early evidence shows that statins are safe and effective in treating hypercholesterolemia after liver transplantation. Studies in cardiovascular disease have shown that statins exhibit beneficial properties independent of lipid-lowering. These include anti-inflammatory effects and improvement in endothelial function. Recently, statins were shown to repress induction of major histocompatibility complex class II complexes by interferon-gamma, which in turn suppresses activation of T lymphocytes. Such effects may assume significance when using statins after solid-organ transplants. Pravastatin has been shown to reduce acute rejection after cardiac and renal transplantation and to also reduce natural killer cell cytotoxicity in these populations. It remains to be seen whether statins will demonstrate similar benefits after liver transplantation.

Long-term management of the liver transplant patient: diabetes, hyperlipidemia, and obesity

1. As long-term survival improves after liver transplantation, cardiovascular complications are emerging as a major cause of late morbidity and mortality. It seems reasonable to correct the potentially reversible cardiovascular risk factors of diabetes, hyperlipidemia, and obesity, in addition to hypertension. 2. The results of liver transplantation in diabetics are acceptable in terms of morbidity, mortality, and prevalence of posttransplant diabetes, but the poor outcomes described in some series suggest that more extensive testing for macro- and microvascular disease may become necessary. 3. The management of diabetes in liver transplant recipients is not substantially different from its management in non-transplant patients, except that steroid reduction or withdrawal and minimizing doses of calcineurin inhibitors are beneficial. 4. Hyperlipidemia occurs in all solid-organ transplantation, with prevalence rates the lowest for liver transplant recipients. Following liver transplantation, between 15% and 40% of recipients on average have increased plasma cholesterol levels and about 40% have hypertriglyceridemia. Dietary changes, weight reduction, exercise and statins are the mainstays of therapy. 5. Retrospective studies suggest that long-term survival of obese recipients after liver transplantation does not differ from nonobese recipients. Posttransplant weight gain occurs in most recipients, and approximately two thirds become overweight. The management of posttransplant obesity is similar to that in non-transplant settings.

Steroid withdrawal in liver transplant recipients

Because of troublesome side effects associated with steroid use, many transplant centers have tried to withdraw steroids from stable, solid organ transplant recipients. The objective of this study was to evaluate the ability to wean liver transplant recipients off steroids, depending on both their primary immunosuppressive regimen and their primary disease state. This was a retrospective, single-center review of steroid weaning in adult orthotopic liver transplant recipients. Based on primary immunosuppression, patients could be weaned off steroids similarly if they were taking cyclosporine or tacrolimus (53.9% vs 61.4%). When triple immunosuppressive regimens were compared with dual regimens, a difference was found in ability to wean patients off steroids (52.4% vs 74.5%, P = .001). When steroid weaning was stratified for primary immunosuppression and primary disease state, patients with autoimmune-mediated diseases (autoimmune hepatitis, sclerosing cholangitis, and primary biliary cirrhosis) were less likely to be weaned if they were receiving cyclosporine-based immunosuppressants (36.8% vs 62.2%, P = .03). In conclusion, it appears that a large number of liver transplant recipients can safely be tapered off steroids.

Blood pressure, endothelial function and circulating endothelin concentrations in liver transplant recipients

OBJECTIVES

To study candidates for liver transplant before and 6 weeks after transplant, and to elucidate the role of endothelial dysfunction and plasma endothelin concentrations in the development of hypertension. DESIGN PROSPECTIVE: follow-up study.

SETTING

Institutional, outpatient.

PATIENTS

and controls Fifteen patients (11 men, four women, mean age 46.7+/-13.2 years) with end-stage liver disease (ESLD) and healthy volunteers of comparable age and sex.

METHODS

We performed office blood pressure readings and 24 h ambulatory blood pressure monitoring (ABPM), measurements of endothelial-dependent vasodilatation using high-resolution ultrasound in the brachial artery at rest and during reactive hyperemia, and plasma endothelin-1 assays 3 months before and 6 weeks after the transplant.

RESULTS

Office systolic and diastolic blood pressures increased significantly 6 weeks after liver transplantation (from 116.6+/-14.1 to 139.9+/-19.5 mmHg and from 68.6+/-9.5 to 84.1+/-9.8 mmHg, respectively; both P < 0.001). Hypertension based on office blood pressure readings increased from 6.7 to 40% (P < 0.05). Mean 24 h systolic blood pressure increased from 118.7+/-10.3 to 140.0+/-19.0 mmHg (P < 0.001), mean 24 h diastolic blood pressure increased from 86.0+/-7.7 to 104.8+/-13.9 mmHg (P < 0.001) and heart rate increased from 74.8+/-10.2 to 80.2+/-8.2 beats/min (P < 0.05). Brachial artery flow-mediated dilatation did not change throughout the study (before transplant: 4.2+/-4.0%; after transplant: 6.3+/-5.4%; NS) and did not differ from that in controls (5.2+/-3.8%). Plasma endothelin-1 was increased in patients with ESLD (15.3+/-2.6 pg/ml) compared with controls (5.6+/-0.4 pg/ ml; P < 0.001) and remained unchanged 6 weeks after liver transplantation (14.1+/-3.7 pg/ml).

CONCLUSION

Our results show increased blood pressure with suppressed circadian blood pressure variability in liver graft recipients 6 weeks after transplant and no change in endothelial function and plasma endothelin concentrations. Therefore, the blood pressure increase documented in our study cannot be explained by endothelial dysfunction. Twenty-four hour ABPM should be performed routinely in patients who have undergone liver transplant.

Promising early outcomes with a novel, complete steroid avoidance immunosuppression protocol in pediatric renal transplantation

BACKGROUND

Corticosteroids have been a cornerstone of immunosuppression for four decades despite their adverse side effects. Past attempts at steroid withdrawal in pediatric renal transplantation have had little success. This study tests the hypothesis that a complete steroid-free immunosuppressive protocol avoids steroid dependency for suppression of the immune response with its accompanying risk of acute rejection on steroid withdrawal.

METHODS

An open labeled prospective study of complete steroid avoidance immunosuppressive protocol was undertaken in 10 unsensitized pediatric recipients (ages 5-21 years; mean 14.4 years) of first renal allografts. Steroids were substituted with extended daclizumab use, in combination with tacrolimus and mycophenolate mofetil. Protocol biopsies were performed in the steroid-free group at 0, 1, 3, 6, and 12 months posttransplantation. Clinical outcomes were compared to a steroid-based group of 37 matched historical controls.

RESULTS

Graft and patient survival was 100% in both groups. Clinical acute rejection was absent in the steroid-free group at a mean follow-up time of 9 months (range 3-13.7 months). Protocol biopsies in the steroid-free group (includes 10 patients at 3 months, 7 at 6 months, and 4 at 12 months) revealed only two instances of mild (Banff 1A) subclinical rejection (reversed by only a nominal increase in immunosuppression) and no chronic rejection. At 6 months the steroid-free group had no hypertension requiring treatment (P=0.003), no hypercholesterolemia (P=0.007), and essentially no body disfigurement (P=0.0001). Serum creatinines, Schwartz GFR, and mean delta height Z scores trended better in the steroid-free group. In the steroid-free group, one patient had cytomegalovirus disease at 1 month and three had easily treated herpes simplex stomatitis, but with no significant increase in bacterial infections or rehospitalizations over the steroid-based group. The steroid-free group was more anemic early posttransplantation (P=0.004), suggesting an early role of steroids in erythrogenesis; erythropoietin use normalized hematocrits by 6 months.

CONCLUSIONS

Complete steroid-free immunosuppression is efficacious and safe in this selected group of children with no early clinical acute rejection episodes. This protocol avoids the morbid side effects of steroids without increasing infection, and may play a future critical role in avoiding noncompliance, although optimizing renal function and growth.

Liver transplantation using sirolimus and minimal corticosteroids (3-day taper)

At our center, we have performed liver transplantation since 1995 with a rapid-taper steroid protocol (weaning steroids by day 14 posttransplantation). Beginning in 2000, we further reduced the use of corticosteroids to 3 days and added sirolimus to our immunosuppressive regimen. We report our experience with 39 patients who underwent liver transplantation with either tacrolimus or cyclosporin A (Neoral; Novartis Pharmaceuticals Corp., Summit, NJ) and sirolimus, with a 3-day tapered dose of corticosteroids. Thirty-two patients received a cadaveric graft and 7 patients received a right hepatic lobe from a living donor. All patients initially were administered either tacrolimus (0.1 mg/kg/d) or cyclosporin A (10 mg/kg/d) and sirolimus (6 mg/d for 1 day, followed by 2 mg/d), in addition to methylprednisolone on the first 3 days (1, 0.5, and 0.5 g/d) after transplantation. Patients were administered corticosteroids for presumptive or biopsy-proven evidence of acute cellular rejection (methylprednisolone, 1, 0.5, and 0.5 g on 3 successive days). Seventeen patients were administered tacrolimus and 22 patients were administered cyclosporin A. Six patients were excluded from analysis because they were administered sirolimus for less than 2 weeks. Mean duration of follow-up was 124 days. Patient survival was 36 of 39 patients (92%), and graft survival was 35 of 39 grafts (89%). Ten of 33 patients (30%) experienced 12 episodes of rejection (7 biopsy proven, 5 presumptive) compared with 70% in historical controls (P <.01). OKT3 was required in 1 of 33 patients (3%) compared with 37% in controls (P <.01). Twenty-six of 33 patients (79%) were not administered prednisone, and 7 of 33 patients (21%) were administered prednisone for reasons other than rejection. Posttransplantation, there was no significant change in values for creatinine, glucose, aspartate aminotransferase, bilirubin, cholesterol, and white blood cell counts. Platelet counts were significantly reduced, and hematocrits were significantly elevated (P <.05). Liver transplantation may be successfully performed with minimal use of corticosteroids by using sirolimus and either tacrolimus or cyclosporin A. Despite the absence of prednisone from our immunosuppressive protocol, the incidence of rejection and OKT3 use was lower than in historical controls. Patient and graft survival rates were identical to those of historical controls. The findings in this report will serve as the basis for a formal trial evaluating the efficacy of sirolimus in liver transplantation.

Tacrolimus conversion improves hyperlipidemic states in stable liver transplant recipients

With improvements in surgical technique and the advent of new and more effective immunosuppressive agents, survival rates in liver transplant recipients have dramatically improved. However, hyperlipidemia frequently develops in patients administered cyclosporine-based immunosuppression long-term, although it appears to occur less often with newer, tacrolimus-based regimens. We sought to determine whether an isolated change in the baseline immunosuppressive regimen (cyclosporine to tacrolimus) would improve hyperlipidemic states in these patients. Twenty-one long-term stable liver transplant recipients with hyperlipidemia, manifested by elevated cholesterol and/or triglyceride levels, were offered conversion to tacrolimus from cyclosporine A therapy. Lipid profiles were monitored at baseline (while on cyclosporine therapy) and at 1 and 3 months after conversion to tacrolimus therapy. There were no other medication manipulations. After conversion to tacrolimus therapy, mean cholesterol levels decreased from 251 to 202 mg/dL at 1 month (P <.001) and 194 mg/dL at 3 months (P <.001). Similarly, triglyceride levels decreased from 300 to 207 mg/dL by 1 month (P =.011) and 203 mg/dL by 3 months (P <.001). There was also a statistically significant decrease for very low-density lipoprotein levels at 3 months (P =.005) and low-density lipoprotein levels at 1 and 3 months (P =.013 and P =.014, respectively). High-density lipoprotein levels did not significantly change after conversion to tacrolimus therapy. Conversion was not accompanied by adverse side effects, and patients tolerated the change well. In conclusion, simple conversion from cyclosporine to tacrolimus-based immunosuppression therapy is safe and improves posttransplantation hyperlipidemia in a subgroup of liver transplant recipients.

Current treatment practice in immunosuppression

New drugs have recently been added that may eventually replace the two-decade dominance of cyclosporin in solid organ transplantation. This cornerstone of immunosuppression was introduced by Borel [1] and Calne [2] in the mid-70s. In 1989, Starzl et al., after 2 years of preclinical experimentation, introduced tacrolimus (originally designated as FK506 by the Fujisawa Pharmaceutical Company of Japan) as a potent immunosuppressant for liver transplants [3]. Also, in recent years, a variety of novel purine and pyrimidine biosynthesis inhibitors have been tested for transplantation therapy. The leading agent which appears to be replacing the 35-year position occupied by azathioprine is the semi-synthetic morpholinoethyl ester of mycophenolic acid (MPA), mycophenolate mofetil (MMF), introduced by Allison [4] and Sollinger [5], and developed by the Syntex Corporation (now Roche Pharmaceuticals). Others, affecting different intra- or intercellular messages amplifying immunity, are in the pipeline.

Steroid withdrawal in liver transplantation: benefits, risks, and unanswered questions

Since the early days of clinical liver transplantation, steroid therapy has constituted the mainstay of maintenance immunosuppression and is still currently combined with cyclosporine or tacrolimus worldwide. Nevertheless, the side effects of long-term steroid administration, particularly diabetes, hypercholesterolemia, arterial hypertension, infections, and bone diseases, including growth retardation in children, have focused the interest on the feasibility of steroid-free immunosuppression. The benefits and the risks of steroid withdrawal (SW) after liver transplantation are overviewed. In adults, early (3 months after transplantation) SW has been validated by several studies, whereas in pediatric recipients, the timing and selection criteria to optimize the risk/benefit ratio of SW still constitute a matter of debate. The identification of the unanswered questions in this field may serve as a framework for future studies to better assess steroid-free immunosuppression after liver transplantation.

Modern immunosuppression

The current treatment of posttransplant lymphoproliferative disease (PTLD) includes prophylaxis at the time of transplant, decreasing or stopping immunosuppresion and initiation of antiviral therapy in patients with polymerase chain reaction or clinical evidence of PTLD, and judicial reintroduction of immunosuppression in patients who have cleared their PTLD and have begun to have rejection. The pharmacology, pharmacokinetics, notable side effects, and toxicities of the immunosuppressive agents are described in this article. At the conclusion of each section the author's current practice with these agents and treatment strategies are described.

The metabolic effects of cyclosporin and tacrolimus

The introduction of cyclosporin and, more recently, tacrolimus in the immunosuppression of transplanted patients has lead to prolonged graft survival and increased patients' life expectancy. It has been therefore possible to evaluate the effects of long-term treatment with these drugs and metabolic alterations in patients on cyclosporin or tacrolimus have been reported by several authors. In particular, the use of these drugs is associated with abnormalities of glucose and lipid metabolism. Post-transplant diabetes is more common with tacrolimus, probably due to more marked effects on the pancreatic beta-cells, whereas increased levels of cholesterol and triglycerides are more frequently associated with cyclosporin treatment, even though, in this latter case, steroid treatment seems to play a major role. Comparison and intervention studies must be planned to evaluate the best therapeutical approaches to control these abnormalities and to assess the possibility to further increase graft and patient survival by appropriate treatment of diabetes and hyperlipidemia.

Towards a specific immunosuppression for pancreas and islet grafts

This brief article is a summary of the presentations at a meeting organized in Lyon, France, to discuss strategies of reducing post-transplant diabetes mellitus and to suggest an ideal immunosuppressive therapy for pancreatic and islet allografts.

Immunologic Aspects of Transplant Management: Pharmacotherapy and Rejection

The intensivist caring for the critically ill transplant patient must be knowledgeable in the management of immunosuppression or have expert help. Critical illness often has a major impact on the absorption and metabolism of immunosuppressive drugs, increasing or decreasing net immunosuppression. Too little immunosuppression brings the risk of graft loss, while too much increases the morbidity and mortality of serious infection. Optimum management often requires the skillful manipulation of dosage and/or routes of drug delivery. In many cases of life-threatening infection, immunosuppression must be discontinued altogether and restarted prior to significant graft injury. The cost of miscalculation is very high. Loss of a renal, pancreas, or small bowel transplant is tragic, while loss of a heart, lung, or liver is usually fatal. Unfortunately the management of immunosuppression is becoming more complex. As the field of transplantation matures, new immunosuppressants are being introduced. Also, more experience and growing numbers of clinical trials are making the required knowledge base ever larger. Each type of transplant has its own set of evolving immunosuppression strategies. This review presents the basic mechanisms of the most widely used drugs and the dangers of immunosuppression. The drugs are then discussed in the context of liver, small bowel, kidney, pancreas, heart, and lung transplantation. Finally, a brief section on the practical pharmacokinetics of the drugs is presented.

Long-term medical complications in patients surviving > or = 5 years after liver transplant

BACKGROUND

Short-term outcomes of liver transplantation are well reported. Little is known, however, about long-term results in liver recipients surviving > or =5 years. We sought to analyze long-term complications in liver recipients surviving > or =5 years after transplant, to assess their medical condition and to compare findings to the general population.

METHODS

We analyzed the chart and database records of all patients (n=139) who underwent liver transplantation at a major transplant center before January 1, 1991. Outcome measures included the presence of diabetes, hypertension, heart, renal or neurological disease, osteoporosis, incidence of de novo malignancy or fracture, or other pathology, body mass index, serum cholesterol and glucose, liver function, blood pressure, frequency of laboratory and clinic follow-up, current pharmacological regimen, and late rejection episodes.

RESULTS

Ninety-six patients (70%) survived > or =5 years. Compared to numbers expected based on U.S. population rates, transplant recipients had significantly higher overall prevalences of hypertension (standardized prevalence ratio [SPR]=3.07, 95% confidence interval [CI], 2.35-3.93) and diabetes (SPR=5.99, 95% CI, 4.15-8.38), and higher incidences of de novo malignancy (standardized incidence ratio [SIR]=3.94, 95% CI, 2.09-6.73), non-Hodgkin's lymphoma (SIR=28.56, 95% CI, 7.68-73.11), non-melanoma skin cancer (estimated SIR> or =3.16) and fractures in women (SIR=2.05, 95% CI, 1.12-3.43). Forty-one of 87 (47.1%) patients were obese, and 23 patients (27.4%) had elevated serum cholesterol levels (> or =240 mg/dl, 6.22 mmol/L), compared to 33% and 19.5% of U.S. adults, respectively. Prevalences of heart or peptic ulcer disease were not significantly higher.

CONCLUSIONS

Liver transplantation is being performed with excellent 5-year survival. Significant comorbidities exist, however, which appear to be related to long-term immunosuppression.

Evidence for impaired glucose effectiveness in cirrhotic patients after liver transplantation

To evaluate the impact of acute and chronic liver disease and single immunosuppression (cyclosporine A [CSA] or FK506) on insulin sensitivity and glucose effectiveness in liver-grafted patients, we performed a frequently sampled intravenous glucose tolerance test (FSIGTT) in nondiabetic patients after orthotopic liver transplantation (OLT) with acute liver failure ([ALF] group, n = 9, with CSA therapy), in patients after OLT with chronic liver disease (CSA group, n = 8; FK506 group, n = 8), and in 9 healthy control subjects. Insulin sensitivity and glucose effectiveness were determined by analyzing glucose and insulin data from the FSIGTT with Bergman's minimal model technique for glucose. The intravenous glucose tolerance index ([KG] ie, the slope of the regression of the logarithm of blood glucose concentration) was not different between the ALF group (2.17 +/- 0.16 min(-1)) and controls (2.29 +/- 0.13 min(-1)), but was lower (P < .05) in both groups with chronic liver disease (CSA group, 1.46 +/- 0.1; FK506 group, 1.61 +/- 0.11 min(-1)) compared with the ALF group (P < .05). A positive relation for the KG and glucose effectiveness was found in all liver-grafted patients and controls. Insulin sensitivity was not different between all liver-grafted patients and controls. The body mass index (BMI) was the overall determinant of insulin sensitivity in all groups. Single immunosuppressive therapy does not impair insulin sensitivity in liver-grafted patients. The lower glucose effectiveness in liver-grafted patients with chronic liver disease but not in patients after ALF points to a defect in the regulation of glucose-mediated glucose uptake in peripheral tissue.

Successful withdrawal of prednisone after adult liver transplantation for autoimmune hepatitis

Corticosteroid withdrawal after orthotopic liver transplantation (OLT) represents an attractive therapeutic option for ameliorating post-OLT metabolic complications, although several reports suggest patients who undergo transplantation for autoimmune hepatitis (AIH) may have a greater incidence of acute and chronic rejection when withdrawn from corticosteroid therapy. The aim of this study is to evaluate the success of corticosteroid withdrawal in patients with AIH after OLT. Twenty-six patients underwent successful OLT for AIH. In 21 of these patients, stable maintenance immunosuppression consisted of cyclosporine (CSA) and prednisone (n = 20) or tacrolimus (TAC) and prednisone (n = 1). In this group, a trial of prednisone withdrawal was initiated when patients were 6 months or more post-OLT, with normal liver function, and receiving an average prednisone dosage of 10 mg/d. Five additional patients treated with either TAC (n = 4) or CSA (n = 1) plus mycophenolate mofetil underwent a 14-day taper of prednisone. Overall, 17 of 25 patients (68%) were successfully withdrawn from corticosteroids, with a mean follow-up of 22 months (range, 1 to 34 months). Of the remaining 8 patients, 5 patients received a lower dosage of prednisone or required prednisone to control inflammatory bowel disease. Only 3 patients remained dependent on prednisone to maintain stable liver allograft function. Withdrawal from 10 to 5 mg of prednisone (n = 21) resulted in four episodes of steroid-responsive and two episodes of steroid-resistant rejection in 3 patients, and 18 of 21 patients (86%) were rejection free. Withdrawal from 5 to 0 mg prednisone (n = 17) resulted in eight episodes of steroid-responsive and no episodes of steroid-resistant rejection in 4 patients; 13 of 17 patients (76%) were rejection free. Of the 5 patients in the 14-day prednisone-taper group, 3 patients had steroid-responsive rejection and 1 patient required OKT3. Seventeen of 21 patients (81%) with AIH were successfully withdrawn from corticosteroids. It is notable that corticosteroid withdrawal was associated with a reduction in serum cholesterol levels, decreased use of antihypertensive agents, and reduced need for insulin or oral hypoglycemic agents. We propose corticosteroid withdrawal should be attempted in patients with underlying AIH who undergo OLT because most will benefit without significantly jeopardizing the liver allograft.

Cyclosporine and tacrolimus (FK506): a comparison of efficacy and safety profiles

Multicenter clinical trials conducted in the United States and Europe to compare the efficacy and safety of cyclosporine with tacrolimus (FK506) have demonstrated comparable long-term patient survival and graft survival in liver and renal transplant recipients. Importantly, treatment with tacrolimus was associated with reductions in the incidence and severity of acute rejection episodes. However, tacrolimus-based therapy was also associated with increased toxicities in comparison to conventional cyclosporine-based therapy. It is becoming increasingly accepted that earlier trials may have employed high or supratherapeutic doses of tacrolimus and may have been unbalanced with respect to study design. In addition, these pivotal comparative trials were performed with the original formulation of cyclosporine, and not the cyclosporine microemulsion preparation. This critical review of the literature focuses on the United States and European tacrolimus multicenter clinical trials and examines the efficacy and safety of the two primary immunosuppressants, cyclosporine and tacrolimus, obtained in these and other studies. The preliminary findings of ongoing studies comparing the efficacy and safety of the improved formulation, cyclosporine microemulsion, with tacrolimus are also discussed. The overall efficacy of the two agents appears to be similar. The safety profile shows differing toxicities of the two medications. The availability of these two immunosuppressants allows the clinician improved options when choosing an immunosuppressive regimen in solid organ transplantation.

A pilot study on the safety and effectiveness of immunosuppression without prednisone after liver transplantation

BACKGROUND

Corticosteroids are commonly used in the immunosuppression therapy after liver transplantation, yet are associated with considerable side effects. Retrospective studies have shown that corticosteroids can be safely withdrawn from months to years after transplant. We prospectively investigated the effects of early immunosuppression without the use of corticosteroids on graft outcome and transplant complications.

METHODS

Forty-five patients undergoing liver transplantation were randomized to receive immunosuppression composed of cyclosporine microemulsion and azathioprine with (n=22) or without prednisone (n=23), in conventional doses. In those patients who received prednisone, this was withdrawn within 3 months after transplant. The median follow-up of survivors was 14 months (range: 6-24). The study end points were to determine graft survival and function, infectious complications, including hepatitis C virus (HCV)-RNA levels in HCV-infected recipients, acute rejection, kidney function, and metabolic complications.

RESULTS

Eleven deaths occurred, 6 of which were in the prednisone group. Two-year survival did not differ between patients treated with or without prednisone (70.2% vs. 78.3%, P=0.83), nor did the causes of death. No differences were observed with regard to graft function, renal function, and infectious complications. In the subset of patients who received transplants for HCV-related cirrhosis, the dynamics of virus replication HCV-RNA was faster among those treated with prednisone. The incidence and severity of acute rejection was similar in the two groups. More than 80% of acute rejections in both groups were classified as mild or moderate and underwent spontaneous resolution. Only two patients in each group had severe acute rejection requiring additional treatment with high-dose steroids. Patients receiving prednisone tended to have greater biochemical signs of cholestasis, higher serum cholesterol and glucose levels, and more frequent insulin requirement than those treated without corticosteroids.

CONCLUSIONS

Liver transplantation can be performed safely without using corticosteroids in the early postoperative course, and there is no need for routine aggressive steroid treatment of established acute rejections.

Serum cholesterol changes in long-term survivors of liver transplantation: a comparison between cyclosporine and tacrolimus therapy

The aim of this study was to compare the long-term effect of tacrolimus and cyclosporine therapies on serum cholesterol levels in liver transplant recipients. We retrospectively studied 127 consecutive adult liver transplant recipients who survived for at least 1 year after transplantation. Basal immunosuppression consisted of cyclosporine plus prednisone in 100 patients and tacrolimus plus prednisone in 27 patients. Hypercholesterolemia was defined as a fasting serum cholesterol level greater than 220 mg/dL. Mean follow-up was 39 months. No statistical significance was found between cyclosporine- and tacrolimus-treated patients regarding age, sex, diagnosis, and previous cholesterol levels; both groups were similar. Significantly more tacrolimus-treated patients were steroid free in the first and second year of follow-up (tacrolimus, 37% and 63%; cyclosporine, 13% and 32%, respectively; P <.01). In the third year of follow-up, this difference was not significant (77% v 56%). The overall incidence of hypercholesterolemia was 34.6% (44 patients). At the end of the study, hypercholesterolemia was found in 24 of 51 and 14 of 70 patients with and without steroids, respectively (P <.002). Also, mean cholesterol levels were 224 +/- 70 and 191 +/- 48 mg/dL before and after steroid withdrawal, respectively, P <.001. Hypercholesterolemia was found in 43.7% of the patients during cyclosporine plus prednisone therapy compared with 46.1% of the patients during tacrolimus plus prednisone therapy (P <.9). Greater mean cholesterol levels were found in the cyclosporine group, particularly in the second and third years of follow-up (P <.01). Hypercholesterolemia was found in 22% of the patients during cyclosporine monotherapy compared with 15% during tacrolimus monotherapy (P <.5). No differences were found in mean cholesterol levels during follow-up when both monotherapy groups were compared. In conclusion, a lower incidence of hypercholesterolemia was achieved in tacrolimus-treated patients, mainly when steroids were still part of the immunosuppressive treatment.

Metabolism and drug interactions of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors in transplant patients: are the statins mechanistically similar?

3-Hydroxy-3-methylglutaryl coenzyme A reductase (EC 1.1.1.88) inhibitors are the most effective drugs to lower cholesterol in transplant patients. However, immunosuppressants and several other drugs used after organ transplantation are cytochrome P4503A (CYP3A, EC 1.14.14.1) substrates. Pharmacokinetic interaction with some of the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, specifically lovastatin and simvastatin, leads to an increased incidence of muscle skeletal toxicity in transplant patients. It is our objective to review the role of drug metabolism and drug interactions of lovastatin, simvastatin, pravastatin, fluvastatin, atorvastatin, and cerivastatin. In the treatment of transplant patients, from a drug interaction perspective, pravastatin, which is not significantly metabolized by CYP enzymes, and fluvastatin, presumably a CYP2C9 substrate, compare favorably with the other statins for which the major metabolic pathways are catalyzed by CYP3A.

Early cyclosporine monotherapy in liver transplantation: a 5-year follow-up of a prospective, randomized trial

Maintenance of adequate immunosuppression and avoidance of side-effects are the goals of long-term management of all organ-transplanted patients. We here report the final results of a prospective, randomized trial comparing early cyclosporine monotherapy versus double-drug therapy (cyclosporine and steroids) in adult liver transplantation patients. One hundred four patients were randomized 3 months after transplantation either to continue (Group I = 50 patients) or to stop steroids (Group II = 54 patients). Patients on a double-drug regimen were maintained long term on methylprednisolone at a dose of 0.1 mg/kg/d. Target cyclosporine trough levels were between 150 and 250 ng/mL in both groups. Our main points of interest were the prevalence of acute and chronic rejections and steroid-related side-effects in the two groups of patients. Mean follow-up was 41 +/- 16 months (range, 4-68 months). Patient actuarial survival 2 and 5 years after randomization was similar in the two groups (82% vs. 83% and 82% vs. 77%). The prevalence of acute rejections after randomization was, respectively, 8% and 4%. A single episode of chronic rejection was observed only in a patient on long-term steroid therapy. Side-effects of steroid therapy were less frequent in patients weaned off steroids, and when considering hypertension and diabetes, the differences between the two groups were statistically significant. Early cyclosporine monotherapy is a safe undertaking in liver transplantation because it allows a significant reduction of steroid-related side-effects without increasing the risk of acute and chronic rejection. After 5 years, patient survival was similar in patients with or without steroids.