Corticosteroids and concomitant medication in the European multicentre study of FK 506 and cyclosporin in primary liver transplantation

The steroid-sparing effect and the use of concomitant medication during the treatment of liver transplant patients with the novel immunosuppressant FK 506 were evaluated within the European multicentre, randomized, parallel-group study in liver transplantation. Patients undergoing primary liver transplantation were randomized to treatment with FK 506 (n = 267) or with a cyclosporin-based immunosuppressive regimen (n = 273). The total cumulative steroid usage was significantly reduced in the FK 506 treatment group, which is likely to have resulted from the lower incidence of acute rejection in these patients. The number of patients receiving antidiabetic, diuretic and antihypertensive therapy did not differ between the two treatment groups, even though the incidence of diabetes mellitus and oliguria was significantly higher in the FK 506 group. It can, therefore, be assumed that in a number of such cases the severity of these events was very mild necessitating no specific therapy.

Glucose metabolism in liver transplant recipients treated with FK 506 or cyclosporin in the European multicentre study

From September 1990 to January 1992, 545 liver transplant patients were randomised to treatment with either FK506 and prednisolone or a conventional cyclosporin-based immunosuppressive regimen (CBIR). Eight European centres participated in the study. Adverse events were reported as defined by each centre. Hyperglycaemia was reported as an adverse event in 30.7% of patients receiving FK 506 compared with 20.5% in the CBIR group (P < 0.01). Diabetes mellitus was reported in 17.2% of patients treated with FK 506 and 9.5% of CBIR-treated patients (P < 0.05). Treatment with insulin was required in 12.0% of patients in the DK 506 treatment group and in 5% in the CBIR group at 6 months. Initially, higher doses of FK 506 were used. During the study, the protocol was changed to allow a lower dose of FK 506. When the early and late cohorts of patients were compared, the incidence of diabetes mellitus fell from 23.9% to 10.5% in FK 506-treated patients but remained relatively constant in the CBIR group (10.4% to 8.7%). The median cumulative doses of i.v. and p.o. corticosteroids were significantly greater in the CBIR group. Thus, in the overall series, the incidence of diabetes mellitus was significantly greater in the FK 506 group as compared with the CBIR group. However, when a lower FK 506 dose was used during the second half of the study, the difference in the incidence of diabetes mellitus disappeared.

Renal complications and development of hypertension in the European study of FK 506 and cyclosporin in primary liver transplant recipients

We examined the occurrence of renal complications and hypertension in 540 primary liver recipients entered into the European liver trial comparing primary FK 506 to a cyclosporin A based immunosuppression regimen (CBIR). No difference in serious renal impairment or mean creatinine levels was observed with similar rates of "kidney failure" (FK 506 9.4% vs. CBIR 7.3%) and dialysis requirements (FK 506 12% vs. CBIR 11%). "Abnormal kidney function", a less serious parameter of renal impairment, was reported in 89 recipients (33%) in the FK 506 group versus 58 (21%) in the CBIR group (P < 0.01). Development of this complication was associated with elevated intravenous FK 506 dosing schedules, with the mean cumulative dose 43% higher than treated patients with unaffected kidney function. In a later cohort of patients where intravenous dosing was lower, no significant difference in renal complications was detectable. The 6-month prevalence rate of systemic arterial hypertension was noted to be lower in the FK 506-treated patients compared to the CBIR group [33 (17.2%) vs. 47 (25.7%)].

Optimal FK 506 dosage in patients under primary immunosuppression following liver transplantation

In a retrospective study, we analysed the FK 506 dosage used in primary liver graft recipients enrolled in the European FK 506 multicenter trial conducted from September 1990 to January 1992. In addition, a second cohort of patients treated more recently in a single centre was investigated. The impact of different dosing strategies on the clinical course of the patients was analysed with special emphasis on the incidence of rejection episodes and FK 506 side-effects. Among the patients enrolled in the European FK 506 multicenter trial, those patients enrolled during the "early" phase of the study received a higher oral FK 506 dose [mean oral dosage on day 7 = 0.19 mg/kg body weight (bw) per day, n = 134] compared to patients enrolled during the "late" period of the study (mean oral dosage on day 7 = 0.14 mg/kg bw per day, n = 133). This lower dosage was the result of several protocol amendments performed to reduce the incidence of FK 506 side-effects. Lowering of the FK 506 dosage was accompanied by a reduction in the long-term prevalence of side-effects such as diabetes (n. s.) or hypertension (P < 0.05), while patient survival and rejection frequency remained constant. Patients treated in centres with online FK 506 blood level monitoring experienced significantly less hypertension, less episodes of diabetes and less rejection episodes compared to patients treated in centres without. The clinical course of those patients enrolled in the multicentre trial was compared with the course of a cohort of liver-grafted patients treated with FK 506 more recently in a single centre. These patients had a further reduction in the FK 506 dosage (0.10 mg/kg bw per day p.o. or less according to whole blood levels, with no intravenous FK 506 administration). When compared to patients enrolled in the multicentre trial, these patients experienced less side-effects (nephrotoxicity, hypertension, serious early neurotoxicity) while adaequate immunosuppression was maintained.

FK 506 primary immunosuppression following emergency liver transplantation for fulminant hepatic failure. European FK 506 Study Liver Group

The efficacy and safety of an FK 506-compared to a cyclosporin A based immunosuppression regimen was examined in liver recipients who underwent transplantation for fulminant hepatic failure in the European FK 506 liver study. A consistent trend towards improved patient and graft survival noted in the FK 506-treated patients was apparent from the first postoperative week (e. g. patient survival: day 7, 95.5% vs. 82.1% and month 6, 72.7% vs. 60.7%). Acute (in particular intractable) rejection was less frequent in the FK 506 group (e. g. cumulative intractable rejection rate at 6 months, 6.2% vs. 22.6%). In a single centre (Kings College Hospital), 17 patients were studied in more detail. The FK 506 treatment group had improved graft function, lower steroid requirements and episodes of infection. Accompanying these benefits, apache 111 and TISS scores were lower in this group in the early posttransplant period. Intensive care discharge was earlier and both treatment groups experienced similar toxicity.

Focus on intractable rejection: 6-month results of the European multicentre liver study of FK 506 and cyclosporin A

The incidence of intractable rejection was evaluated during the course of a multicentre, randomised, parallel-group study comparing the efficacy and safety of FK 506 and conventional cyclosporin A-based immunosuppressive regimens in patients undergoing primary liver transplantation. A diagnosis of intractable rejection was made if there was histological evidence of unchanged or worsening acute rejection, or chronic rejection after two discrete courses of antirejection therapy. Antirejection regimens were specific to each centre. Patients who experienced intractable rejection could be withdrawn from the study. Patients who were withdrawn from the cyclosporin A treatment group could subsequently receive FK 506 therapy and vice-versa. Intractable rejection was diagnosed in 32/540 patients (5.9%): 7/267 patients (2.6%) in the FK 506 treatment group and 25/273 patients (9.2%) receiving cyclosporin A therapy (P < 0.01). Of these 32 patients, 25 were withdrawn from the study: 3 and 22, from the FK 506 and cyclosporin A treatment groups, respectively. All three patients withdrawn from the FK 506 treatment group are alive: two having undergone retransplantation. Of the 22 patients withdrawn from the cyclosporin A group and converted to FK 506 therapy, 6 were retransplanted, 4 of whom subsequently died. A further two patients died without retransplantation. Thus, in 14 of the 16 patients who were still alive at 6 months, the liver graft was saved after conversion to FK 506 treatment. The reduced incidence of intractable rejection in patients receiving treatment with FK 506, together with the successful rescue of patients developing intractable rejection while receiving cyclosporin A, suggests that FK 506 is an effective immunosuppressive agent following orthotopic liver transplantation.

Neurological complications in the European multicentre study of FK 506 and cyclosporin in primary liver transplantation

Neurological complications were examined in a multicentre, randomized, parallel-group study of 545 patients undergoing primary liver transplantation to compare the efficacy and safety of FK 506- and cyclosporin A-based immunosuppressive regimens (CBIR). In an additional analysis, patients were divided into early and late randomized cohorts to detect the influence of protocol amendements that allowed for FK 506 dose reductions. Initial follow-up was for 6 months. Tremor, headache and insomnia were the most frequently reported adverse events involving the neurological system. Whereas these neurological symptoms were observed significantly more often in FK 506-treated patients (P < 0.05 vs. CsA for the overall population), this was no longer the case for the late FK 506 and CBIR cohorts. The risk of FK 506-treated patients developing tremor was related to the initial i.v. dose, the rate of administration of the i.v. dose and the daily dose (P < 0.01). Headache was significantly correlated with the FK 506 dose (P < 0.05), and insomnia was not related to any dosing variable. Major neurological symptoms, including psychosis, convulsion, coma, aphasia and intracranial haemorrhage, were reported with a low frequency (0.4-5.2%), and differences between both treatment groups were neither significant for the overall population nor for the early and late cohorts of FK 506 and CBIR. Data from the late cohorts showed no differences in the overall incidence of neurological adverse events between FK 506- and CBIR-treated patients.

Diversity in organization and the origin of gene orders in the mitochondrial DNA molecules of the genus Saccharomyces

Sequencing of the Saccharomyces cerevisiae nuclear and mitochondrial genomes provided a new background for studies on the evolution of the genomes. In this study, mitochondrial genomes of a number of Saccharomyces yeasts were mapped by restriction enzyme analysis, the orders of the genes were determined, and two of the genes were sequenced. The genome organization, i.e., the size, presence of intergenic sequences, and gene order, as well as polymorphism within the coding regions, indicate that Saccharomyces mtDNA molecules are dynamic structures and have undergone numerous changes during their evolution. Since the separation and sexual isolation of different yeast lineages, the coding parts have been accumulating point mutations, presumably in a linear manner with the passage of time. However, the accumulation of other changes may not have been a simple function of time. Larger mtDNA molecules belonging to Saccharomyces sensu stricto yeasts have acquired extensive intergenic sequences, including guanosine-cytosine-rich clusters, and apparently have rearranged the gene order at higher rates than smaller mtDNAs belonging to the Saccharomyces sensu lato yeasts. While within the sensu stricto group transposition has been a predominant mechanism for the creation of novel gene orders, the sensu lato yeasts could have used both transposition- and inversion-based mechanisms.

A natural chimeric yeast containing genetic material from three species

The Saccharomyces sp. CID1 isolate (CBS 8614) and several other Saccharomyces sensu stricto yeasts were analysed for their mitochondrial and nuclear genes. The data show that Saccharomyces sp. CID1, found so far only in one location in Europe, is a natural hybrid between three different Saccharomyces yeast species. Two of them, Saccharomyces cerevisiae-like and Saccharomyces bayanus-like, are ubiquitous and contributed parts of the nuclear genome; the third, Saccharomyces sp. IFO 1802-like, which has been found only in Japan, contributed the mitochondrial DNA molecule. These data suggest that the yeast cell is able to accommodate, express and propagate genetic material that originates from different species, and the very existence of the resulting natural hybrids indicates that such hybrids are well adapted to their habitats.

New hybrids between Saccharomyces sensu stricto yeast species found among wine and cider production strains

Two yeast isolates, a wine-making yeast first identified as a Mel+ strain (ex. S. uvarum) and a cider-making yeast, were characterized for their nuclear and mitochondrial genomes. Electrophoretic karyotyping analyses, restriction fragment length polymorphism maps of PCR-amplified MET2 gene fragments, and the sequence analysis of a part of the two MET2 gene alleles found support the notion that these two strains constitute hybrids between Saccharomyces cerevisiae and Saccharomyces bayanus. The two hybrid strains had completely different restriction patterns of mitochondrial DNA as well as different sequences of the OLI1 gene. The sequence of the OLI1 gene from the wine hybrid strain appeared to be the same as that of the S. cerevisiae gene, whereas the OLI1 gene of the cider hybrid strain is equally divergent from both putative parents, S. bayanus and S. cerevisiae. Some fermentative properties were also examined, and one phenotype was found to reflect the hybrid nature of these two strains. The origin and nature of such hybridization events are discussed.

Structure and genetic stability of mitochondrial genomes vary among yeasts of the genus Saccharomyces

Several yeast species/isolates belonging to the genus Saccharomyces were examined for the organization of their mtDNAs and ability to generate petite mutants. A general characteristic for all of the mtDNAs tested was that they were very A+T-rich. However, restriction patterns and inducibility of petite mutations revealed a great diversity in the organization and genetic behaviour of mtDNAs. One group of yeasts, Saccharomyces sensu stricto, contains mtDNA ranging in size from 64 to 85 kb. mtDNAs form these yeasts contain a high number of restriction sites that are recognized by the enzymes Haelll and Mspl, which cut specifically in G+C clusters. There are three to nine ori/rep sequences per genome. These yeasts spontaneously generate respiration deficient mutants. Ethidium bromide (Et-Br), at low concentrations, induces a majority of cells to give rise to petites. A second group of yeasts, Saccharomyces sensu lato, contains smaller mtDNAs, ranging in size from 23 to 48 kb, and probably only a few intergenic G+C clusters and no ori/rep sequences. These yeasts also generate petite clones spontaneously. but Et-Br, even when present at high concentrations, does not substantially increase the frequency of petites. In most petite clones from these yeasts only a small fragment of the wild-type molecule is retained and apparently multiplied. A third group, represented by Saccharomyces kluyveri, does not give rise to petite mutants either spontaneously or after induction.

[Intraoperative cholangiography as a routine method? A prospective, controlled, randomized study]

A prospective, controlled, randomized trial was conducted in 275 patients with symptomatic gall stone disease, whose history, laboratory data or sonographical findings did not suggest common bile duct stones. Of these patients, 137 did not undergo intraoperative fluoroscopic cholangiography (IOC), but in the remaining 138 patients IOC was attempted. In 111 cases (80.4%) the biliary system was sufficiently visualized. In 3 patients (2.7%) calculi in the cystic or common bile duct were diagnosed, which would have been overlooked without IOC. IOC was false-positive in one case. One year after the operation the patients were asked to return for a follow-up examination. Three patients in the group without IOC had had symptomatic passage of a stone, and one had a common bile duct stone removed by endoscopic papillotomy. A retained stone was discussed as etiology for a pancreatitis in a fifth patient in this group. No patient sustained long-term sequelae from the retained common bile duct stones. None of the patients in the IOC group had evidence of cholangiolithiasis at follow-up. There was no difference between the study groups concerning the incidence of post-operative complications. The operations with IOC lasted significantly longer (92 +/- 31 min vs 77 +/- 28 min). According to our data and those published earlier, the additional financial and logistic expenditure associated with routine IOC is not justified. Patients with the preoperative suspicion of a common bile duct stone should have endoscopic bile duct clearance (ERCP and EPT) prior to cholecystectomy.

Two-year data from the European multicentre tacrolimus (FK506) liver study

To provide a more definitive assessment of the efficacy and safety of tacrolimus therapy in comparison with cyclosporin, the extended follow-up of the European multicentre study is reported. Two-year Kaplan-Meier estimates indicated significant reductions in acute (tacrolimus 45.4%, cyclosporin 55.8%; P = 0.006), refractory (1.2% versus 6.4%; P = 0.003) and chronic rejection (2.0% versus 6.9%; P = 0.015) despite significantly lower steroid usage in patients receiving tacrolimus therapy. Patient and graft survival rates (80.6% versus 74.8% and 74.5% versus 70.0%, respectively) were also superior, although these failed to reach statistical significance. Safety profiles were comparable for most major categories (including renal, neurological and glucose metabolic disorders) and in certain aspects were more favourable for tacrolimus. Hypertension (28.0% versus 39.6%, P < 0.01) and cytomegalovirus infection (14.8% versus 22.3%, P < 0.01), two events with important long-term clinical consequences, were reported significantly less frequently. Hirsutism (0.0% versus 8.7%, P < 0.01) and gum hyperplasia (0.0% versus 2.3%, P < 0.05) were absent in patients receiving tacrolimus. Tacrolimus appears to provide effective and safe long-term immunosuppression.

Mycophenolate mofetil in renal allograft recipients: a pooled efficacy analysis of three randomized, double-blind, clinical studies in prevention of rejection. The International Mycophenolate Mofetil Renal Transplant Study Groups

BACKGROUND

The search for more effective and less toxic immunosuppressive agents to control transplant rejection has led to the extensive testing of mycophenolate mofetil (MMF) in clinical renal transplantation.

METHODS

A pooled analysis of three phase III, randomized, double-blind, multicenter clinical trials conducted in the United States, Canada, Europe, and Australia was performed to further characterize the efficacy of MMF in renal allograft recipients. The three studies enrolled a total of 1493 patients. Triple- and quadruple-therapy regimens of cyclosporine, corticosteroids, and standardized MMF dosages with and without antilymphocyte induction were used: MMF in twice-daily doses of 1.0 g or 1.5 g (MMF 2 g or 3 g) was compared with placebo (PLA) or azathioprine (AZA). The primary efficacy endpoint in the individual trials was biopsy-proven rejection or treatment failure at 6 months. This pooled analysis focused on graft loss, patient death, incidence and treatment of rejection episodes, and graft function (serum creatinine) at 1 year.

RESULTS

At 1 year, the graft survival rate was 90.4% and 89.2% in the MMF 2 g and 3 g groups, respectively, compared with 87.6% in the PLA/AZA group. This difference was not statistically significant. MMF significantly reduced the incidence of rejection episodes: 40.8% for PLA/AZA patients versus 19.8% and 16.5% for the MMF 2 g and MMF 3 g groups, respectively. Renal function was consistently better for both MMF treatment groups at 3, 6, and 12 months.

CONCLUSIONS

MMF proved superior to AZA as a posttransplant immunosuppressant in conjunction with cyclosporine and corticosteroids. MMF-treated groups showed reduced incidence and severity of rejection episodes, similar graft survival, and better graft function over 12 months.

Two-year data from the European multicentre tacrolimus (FK506) liver study

To provide a more definitive assessment of the efficacy and safety of tacrolimus therapy in comparison with cyclosporin, the extended follow-up of the European multicentre study is reported. Two-year Kaplan-Meier estimates indicated significant reductions in acute (tacrolimus 45.4%, cyclosporin 55.8%; P = 0.006), refractory (1.2% versus 6.4%; P = 0.003) and chronic rejection (2.0% versus 6.9%; P = 0.015) despite significantly lower steroid usage in patients receiving tacrolimus therapy. Patient and graft survival rates (80.6% versus 74.8% and 74.5% versus 70.0%, respectively) were also superior, although these failed to reach statistical significance. Safety profiles were comparable for most major categories (including renal, neurological and glucose metabolic disorders) and in certain aspects were more favourable for tacrolimus. Hypertension (28.0% versus 39.6%, P < 0.01) and cytomegalovirus infection (14.8% versus 22.3%, P < 0.01), two events with important long-term clinical consequences, were reported significantly less frequently. Hirsutism (0.0% versus 8.7%, P < 0.01) and gum hyperplasia (0.0% versus 2.3%, P < 0.05) were absent in patients receiving tacrolimus. Tacrolimus appears to provide effective and safe long-term immunosuppression.

Phase II trial of ftorafur with mitomycin C versus ftorafur with methyl-CCNU in untreated colorectal cancer

In an attempt to substitute ftorafur for burdensome 5-fluorouracil (5-FU) infusions, 52 previously untreated patients were randomized to receive ftorafur with either mitomycin C or methyl-CCNU. Ftorafur was administered monthly as a 2-hour infusion daily x 5 days. Mitomycin C and methyl-CCNU were repeated every 8 weeks. A response rate of 27% (seven responses among 26 patients) was demonstrated on the mitomycin C arm compared to a response rate of 15% (four responses among 26 patients) on the methyl-CCNU arm (P = 0.25). There was no significant difference in the median survival between treatment arms. Central nervous system toxicity occurred in greater than 30% of the patients and appeared to be the limiting factor with ftorafur administration. Alternate schedules of ftorafur should be explored since there appears to be little advantage of a daily ftorafur schedule over conventional 5-FU infusions.