Vasoconstrictor effect of cyclosporin on the mesenteric artery in the dog

To evaluate the effect of cyclosporin (CyA) on the mesenteric arterial bed, studies were performed on the isolated mesenteric artery perfused at a constant flow in 20 dogs. Changes in mesenteric perfusion pressure reflected variations in vascular resistance. Pure powder CyA was dissolved in autologous blood and injected at doses of 5, 10, 20 and 40 mg. Infusions of 5 and 10 mg CyA caused nonsignificant mean increases of 3±2 mm Hg [95% confidence interval (CI)-2 to +7; P>0.05] and 3±3 mm Hg (95% CI-3 to +9; P>0.05) in mesenteric perfusion pressure, with CyA blood levels in the mesenteric vein averaging 466±153 and 692±130 nmol/l, respectively, at the end of the injections. Infusions of 20 and 40 mg CyA caused significant increases in mesenteric perfusion pressure averaging 11±3 mm Hg (95% CI 3–18; P<0.05) and 26±4 mm Hg (95 % CI 16–34; P<0.05), respectively. CyA blood levels at the end of infusion averaged 806±85 and 1118±89 nmol/l, respectively, in the mesenteric vein. Blockade of alpha-adrenergic receptors with phentolamine abolished the CyA vasoconstriction of the mesenteric artery, with the increase in perfusion pressure averaging 16±4 mm Hg before and 3±3 mm Hg after phentolamine (P<0.05). Thus, in the dog, CyA causes an acute vasoconstriction of the mesenteric artery through stimulation of alpha-adrenergic receptors.     

Renal allograft immunosuppression

Serum lipid and lipoprotein profiles were performed in order to investigate lipid abnormalities 2 years post-transplantation in first cadaveric renal allograft recipients immunosuppressed with cyclosporin (CyA), azathioprine (Aza), and methylprednisolone (MP), or with any combination of two drugs. CyA was used in low doses. Total serum cholesterol, triglyceride, LDL cholesterol, HDL cholesterol, HDL2 cholesterol, HDL3 cholesterol, apolipoprotein A1, and apolipoprotein B were determined in 88 prospectively randomized patients with functioning grafts. When considering only the patients who remained on the original randomized treatment, there were no significant differences between the four groups in any of the measured variables. Mean total cholesterol was highest in the group receiving Aza and MP (6.8 mmol/l) and lowest in the group receiving triple therapy (5.8 mmol/l; NS). Mean triglyceride level was highest in the group receiving Aza and MP (2.3 mmol/l) versus 1.8–2.2 mmol/l in the groups receiving triple therapy, Aza+CyA, and CyA+MP. For all patients mean triglyceride level was highest in the group receiving Aza and MP (2.7 mmol/l) and lowest in the group receiving triple therapy (1.7 mmol/l; P<0.05). Mean HDL cholesterol ranged from 1.5 to 1.6 mmol/l in all groups. Neither CyA concentration nor CyA or MP dose correlated with cholesterol or triglyceride concentration. However, the average MP dose was twice as high in the group receiving Aza and MP as in the other two groups employing steroids. Serum cholesterol and triglyceride concentrations were related to body mass index (r=0.28, P=0.045 and r=0.30, P=0.029, respectively). Hyperlipidemia was most common in the group receiving Aza and MP. The frequency of hypercholesterolemia (serum cholesterol level >6.5 mmol/l) was 18%, 45%, 60%, and 35% for the patients continuing with the originally randomized treatment in the groups receiving triple therapy, Aza+CyA, Aza+MP, and CyA+MP, respectively. In a normal Finnish reference population, 35% of all males and 31% of all females have a serum cholesterollevel above 6.5 mmol/l. Thus, only patients receiving Aza and MP had a clearly higher frequency of hypercholesterolemia than that found in a normal population. Taken together, this study shows no lipid abnormalities associated with the use of low-dose CyA for 2 years after transplantation. Hyperlipidemia occurring after transplantation is probably multifactorial and more associated with other risk factors than with the immunosuppressive therapy.     

Impact of long-term immunosuppression with cyclosporin A on serum lipids in stable renal transplant recipients

To determine the impact of long-term immunosuppression on serum lipids in stable renal graft recipients we measured serum lipids and apolipoprotein B concentrations in 20 patients receiving therapy with cyclosporin (CsA) and low-dose prednisolone (CsA/P) and in 18 patients on therapy with azathioprine and maintenance steroids (Aza/P). The patients were matched for age, body mass index, primary renal disease and dose of prednisolone, but not for the duration in transplantation and serum creatinine concentration. Triglyceride concentrations were significantly higher in the CsA/P group than in Aza/P-treated patients: 2.62±0.35 vs 1.62±0.23 mmol/l (P<0.05). Similarly, total cholesterol (C) levels were significantly more elevated in the CsA/P recipients than in the other group: 7.44±0.32 vs 5.84±0.25 (P<0.02). CsA/P patients had higher serum levels of LDL-C (4.79±0.20 vs 3.43±0.19 mmol/l P<0.001) and apolipoprotein B concentrations (191±13 vs 128±9 mg/dl; P<0.001). CsA/P and Aza/P recipients had similar concentrations of HDL-C (1.73±0.13 vs 1.52±0.09 mmol/l; NS). We conclude that in stable renal graft recipients with good transplant function long-term immunosuppression with CsA/P is associated with a more atherogenic lipid status than therapy with Aza/P.     

Hypertension two years after renal transplantation: causes and consequences

The incidence of hypertension 2 years after renal transplantation and the possible causes of hypertension were studied retrospectively. A group of 93 patients treated with cyclosporin (CyA), azathioprine (Aza), and/or prednisolone (Pred) were compared to a group of 31 patients treated with Aza and Pred. There were more patients with hypertension in the CyA group (73%) than in the Aza group (58%). Hypertension before transplantation predisposed to hypertension after transplantation. After transplantation, hypertension was most common among patients with polycystic kidney disease (46%), chronic glomerulonephritis (67%), and diabetes (71%). The accumulated immunosuppressive medication (CyA/Pred) did not affect the occurrence of hypertension. Hypertensive patients had significantly poorer graft function than did normotensive patients (serum creatinine level 229 mol/l vs 162 mol/l, P<0.01). The 10-year graft survival was markedly impaired in the group with hypertension (42% vs 65% for normotensives, P<0.05). The 10-year patient survival was 59% vs 79% (P=NS). The study further confirms the frequent finding that hypertension has a negative effect on graft and patient survival rates.     

Renal allograft immunosuppression

We have investigated the impact of triple drug immunosuppression on the occurrence of early inflammatory episodes, as detected by fine needle aspiration biopsy, and of episodes of clinical rejection during the immediate postoperative period. The prospective component of this study includes 128 consecutive first cadaveric renal transplant recipients receiving triple drug treatment consisting of azathioprine (Aza), cyclosporin (CyA) and methylprednisolone (MP). For controls we have used three historical groups: one immunosuppressed with Aza and MP (group A), another with CyA monotherapy (group B), and the third with CyA together with MP (group C) in equivalent drug dosages. On the average, 0.8 episodes of inflammation per patient were recorded during the immediate postoperative period of 30 days with triple drug treatment. This was significantly less than the 1.3 episodes in patients receiving Aza and MP (P<0.01), the 1.7 episodes in patients on CyA monotherapy (P<0.001), or the 1.6 episodes in patients receiving CyA together with MP (P<0.001). Although the first episode of inflammation commenced concurrently in each group and the peak intensity of inflammation was the same, the mean duration of inflammation was significantly shorter-2.7 days-under triple drug treatment than the 7.8–11.7 days for controls (P<0.001). The frequency of rejection episodes under triple treatment was also significantly lower-0.2 per patient-than the 0.8 per patient in controls (P<0.001). The first rejection episode occurred later in the triple drug treatment group-on the average, on day 15.2-than in the historical controls (on days 7.7–11.7). There was, however, no difference in the duration of rejection. There were no differences in patient survival between the four groups. Graft survival was 97% at 10 weeks for triple drug-treated recipients and 79%, 68%, and 87% for first grafts in groups A, B, and C, respectively. Disregarding a minor demographic bias for the triple drugtreated group with respect to preformed antibodies and preoperative dialysis treatment, the study suggests that the triple drug protocol, in the short run, is superior to any conceivable double drug combination or CyA monotherapy.     

Rescue therapy with tacrolimus (FK 506) in renal transplant recipients —a Scandinavian multicenter analysis

All renal allograft recipients (n = 32) in Sweden and Norway who were converted from cyclosporin(CyA)-based immunosuppression to FK 506 (tacrolimus) between October 1992 and June 1995 were analyzed retrospectively. The reasons for conversion were acute refractory rejection (n = 21), chronic rejection (n = 4), and suspected CyA toxicity (n = 6); one patient was converted for psychological reasons. The mean time from transplantation to conversion was 29 (range 1–243) weeks and there was a mean follow-up of 46 (2–143) weeks. Overall graft survival was 59%, with graft survival 52% in patients converted because of acute rejection, 50% in patients converted because of chronic rejection, and 83% in patients converted because of CyA toxicity. There was no significant correlation between preconversion serum creatinine and outcome. Seventy-two percent of the patients had significant side effects during FK 506 treatment, the most frequent ones being neurological and gastrointestinal symptoms. These improved after dose reduction. Two patients became overimmunosuppressed and developed lymphoma. One patient died of the primary kidney disease, hemolytic uraemic syndrome. We conclude that FK 506 therapy is able to salvage kidneys with acute refractory rejection and that it is an alternative in patients with CyA toxicity. However, the risk of overimmunosuppression must be considered.     

Conversion to tacrolimus after liver transplantation

We have reviewed our experience with conversion to tacrolimus after 435 liver transplantations. Tacrolimus was administered as a rescue agent in 33 patients until October 1993. Indications for rescue therapy were: cholestatic forms of severe, steroid-resistant cellular rejection (n=8), OKT3-resistant cellular rejections (n=6), cellular rejections in patients suffering from cyclosporin malabsorption (n=4), late onset cellular rejections (n=4), early chronic rejections (n=3), and chronic vascular or ductopenic rejections (n=8). Response was evident in 29 of the 33 patients (88%), whereas 4 patients (12%) were nonresponsive. Patient and graft survival were 76% and 70%, respecitively. Graft loss with or without patient death occurred in three of eight patients suffering from severe, steroid-resistant cellular rejection, in two of six patients with OKT3-resistant cellular rejections, and in five of eight patients undergoing chronic rejection. In severe steroid-resistant cellular rejection, successful tacrolimus rescue therapy corresponded to a significantly lower total serum bilirubin than unsuccessful therapy (12.0±5.6 mg% vs 29.7±5.9 mg%, P(0.05). We conclude that tacrolimus rescue therapy is a safe and efficient alternative for high-risk cases that do not respond to conservative treatment. In severe, steroid-resistant cellular rejection and in chronic ductopenic rejection, conversion to tacrolimus is beneficial only in a limited number of cases. A predictive parameter, which total serum bilirubin may prove to be in severe, steroid-resistant cellular rejection, is needed to select those cases that might benefit more from retransplantation than from conversion to tacrolimus.     

Renal allograft immunosuppression: I. Early inflammatory and rejection episodes in triple drug treatment compared to double drug combinations or cyclosporin monotherapy

Abstract. We have investigated the impact of triple drug immunosuppression on the occurrence of early inflammatory episodes, as detected by fine needle aspiration biopsy, and of episodes of clinical rejection during the immediate postoperative period. The prospective component of this study includes 128 consecutive first cadaveric renal transplant recipients receiving triple drug treatment consisting of azathioprine (Aza), cyclosporin (CyA) and methylprednisolone (MP). For controls we have used three historical groups: one immunosuppressed with Aza and MP (group A), another with CyA monotherapy (group B), and the third with CyA together with MP (group C) in equivalent drug dosages. On the average, 0. 8 episodes of inflammation per patient were recorded during the immediate postoperative period of 30 days with triple drug treatment. This was significantly less than the 1. 3 episodes in patients receiving Aza and MP (P < 0. 01), the 1. 7 episodes in patients on CyA monotherapy (P < 0. 001), or the 1. 6 episodes in patients receiving CyA together with MP (P < 0. 001). Although the first episode of inflammation commenced concurrently in each group and the peak intensity of inflammation was the same, the mean duration of inflammation was significantly shorter-2. 7 days-under triple drug treatment than the 7. 8–11. 7 days for controls (P < 0. 001). The frequency of rejection episodes under triple treatment was also significantly lower-0. 2 per patient-than the 0. 8 per patient in controls (P < 0. 001). The first rejection episode occurred later in the triple drug treatment group-on the average, on day 15. 2-than in the historical controls (on days 7. 7–11. 7). There was, however, no difference in the duration of rejection. There were no differences in patient survival between the four groups. Graft survival was 97% at 10 weeks for triple drug-treated recipients and 79%, 68%, and 87% for first grafts in groups A, B, and C, respectively. Disregarding a minor demographic bias for the triple drug-treated group with respect to preformed antibodies and preoperative dialysis treatment, the study suggests that the triple drug protocol, in the short run, is superior to any conceivable double drug combination or CyA monotherapy.     

Renal allograft immunosuppression

A prospective randomized study was conducted to evaluate the impact of four different conversion protocols on graft outcome in long-term follow-up. Between January 1986 and May 1987, 128 patients with first cadaveric kidnery allografts were randomized at the time of transplantation to four treatment groups of 32 patients each, to be assigned 10 weeks post-transplantation. During the first 10 weeks, all patients received triple therapy with low-dose azathioprine (Aza), cyclosporin (CyA), and methylprednisolone (MP). After 10 weeks, one group continued with triple therapy (group A) while the three other groups received different combinations of two drugs, namely, Aza and CyA (group B), Aza and MP (group C), or CyA and MP (group D). Withdrawal of MP (group B) or especially of CyA (group C) was associated with 4/29 (14%) and 10/28 (36%) acute rejection episodes, respectively, for 60 days after conversion. All rejections were mild and reversible. There were no rejections after Aza withdrawal or in the group that continued on triple therapy during the corresponding time period. The most common reason for dropping out after withdrawal, for those patients who could not continue on the originally randomized medication, was azathioprine intolerance (n=12). Five patients were switched back to triple therapy after CyA withdrawal due to rejection. Steroid intolerance was rare and CyA in low doses was very well tolerated. At 1 year there were no statistically significant differences in graft survival between groups A, B, C, and D-81%, 88%, 88%, and 88%, respecively-or in patient survival-88%, 88%, 88%, and 97%, respectively. For those patients continuing with the originally randomized treatment protocol, there were no differences in patient or graft survival either, the means being 91% and 89%, respectively. The most common cause of death after withdrawal was cardiovascular in nature, and there were no more fatal infections under triple drug treatment than with double drug regimens. There were no statistically significant differences in mean serum creatinine values at 1 year. The median serum creatinine values for groups A, B, C, and D were 112, 132, 133, and 133 mol/l, respectively. At 1 year the mean CyA dose in the groups that continued with CyA was 3.5–4.2 mg/kg per day and CyA concentrations were equal.     

Cyclosporin A-induced transient rise in plasma alkaline phosphatase in kidney transplant patients

In 1981 cyclosporin A (CyA) became available and replaced azathioprine (Aza) as the immunosuppressive agent in kidney transplantation at the University Hospitals in Basel, Switzerland. Patients on CyA and prednisone (CyA/p) therapy frequently demonstrated an isolated rise in bone-derived serum alkaline phosphatase (aP) concentration, but patients on Aza and prednisone (Aza/p) therapy did not. On the basis of long-term aP concentration and using noninvasive means, the present retrospective study was designed to investigate biochemical markers and radiographic signs of bone disease after successful kidney transplantation in patients on Cya/p treatment. Similar investigations were performed in patients on Aza/p and the results were compared. Follow-up examinations included clinical examination, radiography of the hand, and biochemical analysis of serum and urine. In 139 renal transplant patients on CyA/p, aP increased transiently after successful grafting (at transplantation 84±43 U/l; on day 90, 112±82 U/l). In 50 patients aP levels were higher at the time of transplantation (120±80 U/l) and aP peaked after 8±6 months, at a mean concentration of 242±103 U/l. In these patients aP concentrations exceeded the normal range for 16±10 months. None of the patients on CyA/p showed symptoms of bone disease when aP was increased. Radiological surveys revealed more pronouced osteodystrophy in patients at the time of transplantation, which increased aP to above the normal range after transplantation. Despite this rise in aP, over the long term bone lesions improved radiographically while bone mass remained stable. In constrast, patients treated with Aza/p demonstrated a significant decrease in aP level after transplantation from 75±33 U/l to 54±29 U/l on day 90. In addition, radiographic bone changes persisted and bone mass decreased significantly. After a 2-year follow-up, serum parathyroid hormone, 1,25-(OH)₂-vitamin D₃, calcium, and phosphorus concentrations, urinary excretion of hydroxyproline, and tubular reabsorption of phosphate did not differ between patients on CyA/p and controls on Aza/p. We conclude that after successful kidney transplantation and initiation of CyA/p therapy, a transient increase in bone-derived aP frequently occurred. These patients more often demonstrated radiographic signs of pre-existing osteodystrophy. However, over the long term, these changes improved.     

Effect of adding Mycophenolate mofetil in paediatric renal transplant recipients with chronical cyclosporine nephrotoxicity

Cyclosporine (CyA) has made a great impact on 1-year allograft survival, however, after years, renal function deteriorates, possibly due to chronic toxicity. Recently, Mycophenolate mofetil (MMF) was introduced as a non-nephrotoxic immunosuppressant that might be effective in chronical transplant arteriolopathy. We therefore started MMF at a dose of 600 mg/m² b. i. d. in 18 pediatric renal transplant recipients (10.8 ± 3.9 (SD) years of age at transplantation, 11/18 with a history of rejections) with biopsy-proven chronic arteriolopathy and other signs of CyA toxicity at a mean follow up time of 6.2 ± 2.7 (range 2.3–11.8) years after transplantation. One month prior to conversion, mean serum creatinine was 171 ± 96 μmol/l, lower than at the time of conversion (188 ± 100 μmol/l, P = 0.003, paired t-test). At last follow-up (median 13.7 months, range 5.0 to 25.0 months) after conversion, mean serum creatinine decreased significantly to 127 ± 69 μmol/l (P = 0,0003, paired t-test). The CyA dosage was reduced from a mean of 150 ± 39 mg/m2 per day to 59 ± 13 mg/m² per day in 7 patients, and CyA was discontinued in 11 patients after a median period of nine months (range 1–18 months). After a median period of 21 days, a pharmacokinetic profile was performed in all patients. The mean MMF dose was 1117 ± 319 mg/m² per day (range 675–1774 mg/m² per day). The mean Mycophenolic acid (MPA) trough concentration was 4.0 ± 2.0 μg/ml, range 1.4–7.9 μg/ml. Mean 12 h MPA AUC was 70.6 ± 28.1 (range 31.9–127) μg × h/ml. Except for one patient with diarrhea associated with a high AUC, and for one patient with a steroid-sensitive rejection episode after 566 days, no other patient experienced side effects or a rejection episode. Prednisolone was left unaltered at 2–4 mg/m² per day. We conclude that MMF allows safe reduction of CyA with markedly better graft function, suggesting that chronical CyA-toxicity partially accounts for deteriorating allograft function. Received: 20 April 1999 Revised: 9 January 2000 Accepted: 15 March 2000     

Long-term renal allograft function under maintenance immunosuppression with cyclosporin A or azathioprine

In order to evaluate long-term renal graft function, 149 cyclosporin A and prednisolone (CyA/P)-treated renal transplant recipients were compared with 119 azathioprine and prednisolone (Aza/P)-treated patients. Only patients who had a functioning graft for at least 1 year and who were maintained on their initial immunosuppressive protocol were included. The minimum follow-up period was 4 years. Renal graft function was estimated by yearly determinations of serum creatinine and creatinine clearance. The CyA/P-treated patients had a significantly higher serum creatinine and a significantly lower creatinine clearance at every point in time posttransplantation than Aza/P-treated patients (P<0.001). The evolution of renal graft function, as reflected in the line of regression for serum creatinine and creatinine clearance versus time, was estimated for each individual patient. There was an almost stable renal function, as assessed by the median of the slopes of the regression line for serum creatinine versus time in both groups. The median increase in serum creatinine was only 1.4 mol/l per year for Aza/P-treated patients and 2.4 mol/l per year for CyA/P-treated patients (difference NS). The median decline in creatinine clearance was 2.18 ml/min per 1.73 m²/year in the Aza/P group and 1.07 ml/min per 1.73 m²/year in the CyA/P group (P=0.05). In patients with a functioning graft for at least 5 years, creatinine clearance remained unchanged in both groups during the study period. In conclusion, renal graft function, as assessed by measurements of serum creatinine and creatinine clearance, remained essentially unchanged for at least 5 years after transplantation, regardless of the immunosuppressive protocol used. Thus, these data do not indicate a progression with time of the nephrotoxicity observed in CyA-treated patients.     

Effects of growth hormone administration in pediatric renal allograft recipients

The efficacy of recombinant human growth hormone (rGH) was assessed in five pediatric allograft recipients with severe growth retardation despite successful renal transplants. rGH 0.05 mg/kg per dose was given six times weekly by subcutaneous injection to five prepubertal children (mean age 15.2±2.0 years) all of whom had bone ages less than or equal to 12 years (10.0±1.4 years), a height standard deviation score of less than –2.5 (–4.9±1.5), no evidence of catch-up growth, a calculated glomerular filtration rate (GFR) of more than 40ml/min per 1.73 m² (51±6.8 ml/min per 1.73 m²), and stable renal function on alternate-day prednisone (16.7±2.6 mg/m² per dose). Growth hormone profiles were abnormal in all children before treatment. rGH administration led to a significant increase in both growth rate (3.5±1.6 cm/year pre therapy, 8.5±1.4 cm/year post therapy,P<0.001) and percentage of expected growth velocity for bone age (67±31% pre therapy, 163±27% post therapy,P<0.001) with evidence of true catch-up growth. During the study period, three children had the appearance of secondary sexual characteristics, and one had premature advancement of his bone age. GFR decreased in three children, and in one rGH was discontinued due to a steady rise in serum creatinine. No significant changes were seen in serum calcium, phosphorus, cholesterol, triglycerides, glucose, or thyroid function, although a significant increase in alkaline phosphatase was found. In summary, growth-retarded pediatric renal allograft recipients may have abnormal endogenous GH production and respond favorably to rGH. The potential risk of deterioration in renal function due to rGH-induced hyperfiltration must be investigated.     

Acute effect of cyclosporin on renal function following the initial changeover to a microemulsion formulation in stable kidney transplant patients

Potential differences in the acute effect of cyclosporin on renal function when dosed orally as the current market formulation or following a milligram-to-milligram conversion to a new microemulsion formulation were investigated in 14 stable kidney transplant patients. The study consisted of three sequential periods of 2 weeks duration each. Patients entered (period I) and completed (period III) the investigation with the market formulation and received the microemulsion formulation in period II; individualized cyclosporin doses remained unchanged throughout the study. Over one steady-state dosing interval at the end of each study period, whole blood cyclosprin pharmacokinetic profiles were assessed in parallel with endogenous creatinine clearances over sequential 1-to 2-h intervals. The rate and extent of cyclosporin absorption were significantly greater (P<0.01) from the microemulsion formulation with average increases of 73% in peak concentration and 44% in area under the curve compared to the market formulation. Sequential creatinine clearances exhibited a transient decrease with the nadir occurring on average between 4 and 6h post dose followed by a rapid return to baseline. Specifically in period I on the market formulation, clearances decreased from a baseline of 71.7±20.6 to a minimum of 51.1±17.9 ml/min per 1.73 m² (similar values in period III) and from 76.8±24.8 to 53.5±17.5 ml/min per 1.73 m² in period II on the microemulsion. Neither the baseline nor minimum clearances were significantly different among the study periods. Hence, the pharmacokinetic differences between the formulations did not acutely influence the pattern of glomerular filtration rate following the initial milligramto-milligram changeover in stable renal transplant patients.     

Renal allograft immunosuppression: IV. Comparison of Iipid and lipoprotein profiles in blood using double and triple immunosuppressive drug combinations

Abstract. Serum lipid and lipoprotein profiles were performed in order to investigate lipid abnormalities 2 years post-transplantation in first cadaveric renal allograft recipients immunosuppressed with cyclosporin (CyA), azathioprine (Aza), and methylprednisolone (MP), or with any combination of two drugs. CyA was used in low doses. Total serum cholesterol, triglyceride, LDL cholesterol, HDL cholesterol, HDL2 cholesterol, HDL3 cholesterol, apolipoprotein A1, and apolipoprotein B were determined in 88 prospectively randomized patients with functioning grafts. When considering only the patients who remained on the original randomized treatment, there were no significant differences between the four groups in any of the measured variables. Mean total cholesterol was highest in the group receiving Aza and MP (6.8 mmol/l) and lowest in the group receiving triple therapy (5.8 mmol/l; NS). Mean triglyceride level was highest in the group receiving Aza and MP (2.3 mmol/1) versus 1.8–2.2 mmol/l in the groups receiving triple therapy, Aza + CyA, and CyA + MP. For all patients mean triglyceride level was highest in the group receiving Aza and MP (2.7 mmol/1) and lowest in the group receiving triple therapy (1.7 mmol/l; P<0.05). Mean HDL cholesterol ranged from 1.5 to 1.6 mmol/l in all groups. Neither CyA concentration nor CyA or MP dose correlated with cholesterol or triglyceride concentration. However, the average MP dose was twice as high in the group receiving Aza and MP as in the other two groups employing steroids. Serum cholesterol and triglyceride concentrations were related to body mass index (r= 0.28, P= 0.045 and r= 0.30, P= 0.029, respectively). Hyperlipidemia was most common in the group receiving Aza and MP, The frequency of hypercholesterolemia (serum cholesterol level > 6.5 mmol/1) was 18%, 45%, 60%, and 35% for the patients continuing with the originally randomized treatment in the groups receiving triple therapy, Aza + CyA, Aza + MP, and CyA + MP, respectively. In a normal Finnish reference population, 35% of all males and 31% of allfemaleshaveaserumcholesterollevel above 6.5 mmol/l. Thus, only patients receiving Aza and MP had a clearly higher frequency of hypercholesterolemia than that found in a normal population. Taken together, this study shows no lipid abnormalities associated with the use of low-dose CyA for 2 years after transplantation. Hyperlipidemia occurring after transplantation is probably multifactorial and more associated with other risk factors than with the immunosuppressive therapy.     

Randomised open clinical trial of conversion from mycophenolate mofetil to azathioprine in cadaveric renal transplantation

Abstract Mycophenolate mofetil (MMF) is a powerful immunosuppressive drug with established efficacy and safety. The search for a less expensive immunosuppressive protocol has led to an open randomised clinical trial of conversion from MMF to azathioprine (Aza). A total of 28 renal allograft recipients treated with prednisone, cyclosporine, and MMF was randomised into two groups: converted (early conversion) and control (late conversion). Conversion from MMF to Aza was conducted at the end of the 4th post‐transplant month in the converted group and after the 12th month in the control. During the 20‐month observation period, biopsy‐proven acute rejection occurred more frequently in the converted than in the control group, although the difference was not statistically significant. Early conversion from MMF to Aza increased the risk of subsequent rejection in those patients who underwent at least one episode of acute rejection prior to conversion.     

Cyclosporin A in fat emulsion carriers: studies on the immunosuppressive potential,using the heterotopic heart transplant model in rats

Cyclosporin A (CyA) is an extremely lipophilic drug that needs a solubilizing agent to become soluble in water. In the commercially available intravenous formulation-Sandimmun-Cremophor EL is used for this purpose. It is likely that Cremophor EL contributes to some of the side effects produced by i. v. Sandimmun. We have recently shown that if Cremophor EL is replaced by a soybean oil (SBO)-based fat emulsion carrier, the acute renal side effects following i. v. administration of CyA are avoided in a rat model. It is then important to ascertain whether the use of a fat emulsion carrier alters the immunosuppressive effect of CyA. Moreover, fatty acids can themselves influence the immune system, and both omega-3 and omega-6 fatty acids have been reported to possess immunosuppressive properties. In the present study, the effect on graft survival of i. v. CyA administered in five different formulations, using fat emulsions or liposomes as carriers, was compared to that of conventional Sandimmun infusion substance in the heterotopic heart transplant model in rats. The new formulations tested did not reduce the immunosuppressive effect of CyA. On the contrary, a small but significant increase in graft survival was noted in the groups given CyA in the SBO-based fat emulsion carrier (17.0±0.82 days) and CyA in liposomes (16.0±0.63 days) as compared to the results in the Sandimmun-treated group (15.0±0.58 days: P<0.01 and P<0.05, respectively).     

Renal allograft immunosuppression: II. A randomized trial of withdrawal of one drug in triple drug immunosuppression

Abstract. A prospective randomized study was conducted to evaluate the impact of four different conversion protocols on graft outcome in long-term follow-up. Between January 1986 and May 1987, 128 patients with first cadaveric kidney allografts were randomized at the time of transplantation to four treatment groups of 32 patients each, to be assigned 10 weeks post-transplantation. During the first 10 weeks, all patients received triple therapy with low-dose azathioprine (Aza), cyclosporin (CyA), and methylprednisolone (MP). After 10 weeks, one group continued with triple therapy (group A) while the three other groups received different combinations of two drugs, namely, Aza and CyA (group B), Aza and MP (group C), or CyA and MP (group D). Withdrawal of MP (group B) or especially of CyA (group C) was associated with 4/29 (14%) and 10/28 (36%) acute rejection episodes, respectively, for 60 days after conversion. All rejections were mild and reversible. There were no rejections after Aza withdrawal or in the group that continued on triple therapy during the corresponding time period. The most common reason for dropping out after withdrawal, for those patients who could not continue on the originally randomized medication, was azathioprine intolerance (n= 12). Five patients were switched back to triple therapy after CyA withdrawal due to rejection. Steroid intolerance was rare and CyA in low doses was very well tolerated. At 1 year there were no statistically significant differences in graft survival between groups A, B, C, and D-81 %, 88%, 88%, and 88%, respectively-or in patient survival-88%, 88%, 88%, and 97%, respectively. For those patients continuing with the originally randomized treatment protocol, there were no differences in patient or graft survival either, the means being 91% and 89%, respectively. The most common cause of death after withdrawal was cardiovascular in nature, and there were no more fatal infections under triple drug treatment than with double drug regimens. There were no statistically significant differences in mean serum creatinine values at 1 year. The median serum creatinine values for groups A, B, C, and D were 112, 132, 133, and 133 μmol/l, respectively. At 1 year the mean CyA dose in the groups that continued with CyA was 3. 5–4. 2 mg/kg per day and CyA concentrations were equal.     

The beneficial effects of oral nifedipine on cyclosporin-treated renal transplant recipients — a randomised prospective study

The aim of this study was to test the hypothesis that nifedipine will improve graft survival in cyclosporin A (CyA)-treated renal transplant recipients. One hundred and forty-seven patients were randomised to one of three regimens. Group A received CyA, 7 mg/kg per day, and prednisolone; group B followed the same regimen as group A plus oral nifedipine and group C received CyA, 4 mg/kg per day, prednisolone and azathioprine. Calcium channel blockers were avoided in groups A and C. The crude 2-year (P=0.0223) and 4-year (P=0.0181) graft survival was significantly better in group B (86% and 81%, respectively) than in group A (75% and 63%, respectively). Delayed initial function was seen least frequently in group B (10.2%) compared to groups A (31%) and C (28%; P<0.01). Group B also experienced fewer rejection episodes than groups A and C (P<0.05). We conclude that the combination of oral nifedipine and CyA significantly improves initial graft function, rejection frequency and long term graft survival.     

Impact of early cyclosporin average blood concentration on early kidney transplant failure

This retrospective study served to examine the correlation between the degree of cyclosporin (CyA) exposure, as estimated by a single pharmacokinetic (PK) profile performed at 1 week post-transplant, and the outcome of 290 consecutive renal transplants performed over a 6-year period. For this retrospective analysis patients were stratified into four historical groups based on 12- versus 24-h PK studies and on the use of radioimmunoassay versus fluorescence polarization immunoassay methods for estimates of CyA concentrations. Four PK measures – trough concentration (C₀), average concentration values (C_av; i. e., the dosing interval-corrected area under the concentration-time curve), maximum concentration (C_max), and time to maximum concentration (t_max) – were examined as predictors of patient, graft, and rejection-free survival rates for each of the four groups individually and for all groups combined. Patients with an initial C_av≥ 550 ng/ml had higher 1-year (88 %) and 6-year (66 %) graft survival rates than patients with C_av < 550 ng/ml, who had 1- and 6-year graft survival rates of 80 % and 59 %, respectively (P = NS). Statistically significant differences were observed in graft survival rates between patients with C_av < 550 versus C_av≥ 550 ng/ml at 30 (88 % vs 96 %; P < 0.02), 60 (85 % vs 94 %; P < 0.007), 90 (85 % vs 94 %; P < 0.02), and 180 (83 % vs 92 %; P < 0.05) days. Moreover, patients with C_av < 550 ng/ml displayed more severe rejection episodes, as judged by Banff classification, than patients who displayed C_av≥ 550 ng/ml (grades II and III; 71 % vs 50 %; P = 0.036). In contrast, the C₀, C_max, and t_max values did not correlate with patient, graft, or rejection-free survival rates. The pharmacokinetic parameter of C_av correlated strongly with early graft survival and may, therefore, be a useful predictor of those renal transplant patients who may require more intensive post-transplant monitoring of CyA concentrations by serial PK studies to improve graft survival. Received: 27 May 1997 Received after revision: 8 August 1997 Accepted: 21 August 1997