Cyclosporine Monitoring Research Articles

Monitoring treatment with cyclosporine microemulsion in myasthenia gravis

To examine whether the monitoring of cyclosporine (CsA) blood concentrations is of benefit in CsA microemulsion pre-concentrate (MEPC) therapy for myasthenia gravis (MG). We measured CsA blood concentrations both 2 h after administration (C2) and immediately before administration (C0) and examined associations with changes to clinical parameters in 20 MG patients treated with CsA MEPC in an unblinded, 6-month prospective open trial. Initial dose of CsA MEPC (4.7 +/- 0.5 mg/kg/day) provided both high C2 levels and safe C0 levels. Disease severity, daily dose of prednisolone, acetylcholine receptor-antibody titre levels and levels of interleukin-2 production by peripheral blood mononuclear cells were significantly reduced following treatment with CsA MEPC. A significant correlation existed between C2 levels following the initial dose and clinical improvement in responder MG patients. C0 levels were significantly higher in patients who exhibited increased serum creatinine or hypertension compared with patients free from side effects. Body mass index of individual patients was significantly correlated with C0 level, and may thus offer a useful marker to predict C0 levels. CsA MEPC was effective at suppressing symptoms and T-cell-dependent pathogenesis of MG, and monitoring of C2 and C0 levels can be useful to estimate efficacy and safety of the drug.

A randomized, prospective, pharmacoeconomic trial of neoral 2-hour postdose concentration monitoring versus tacrolimus trough concentration monitoring in de novo liver transplant recipients

Two-hour postdose cyclosporine (C2) monitoring is becoming an accepted method of therapeutic drug monitoring, although it is not known whether C2 monitoring is superior to tacrolimus (FK)-based immunosuppression. The purpose of this trial was to compare the safety, efficacy, and pharmacoeconomics of cyclosporine A (CsA) monitored by C2 levels versus FK monitored by trough levels in de novo liver transplant recipients. After informed consent, 60 de novo liver transplant recipients were randomized in a 1:1 fashion to receive either FK (trough, 6-10 ng/mL) or CsA (C2, 600-1200 ng/mL) and corticosteroids. The 2 groups were similar for gender, race, indication for liver disease, and age. At 1 year, patient survival was similar (93% for FK versus 90% for C2). One patient in the FK arm was retransplanted because of recurrent hepatitis C virus (HCV). Early acute rejection occurred in 27% of FK-treated patients and 23% of CsA-treated recipients [P = not significant (NS)]. Recurrent HCV occurred in 21% of FK-treated patients and 61% of CsA-treated patient (P = 0.04). The incidence of other infections, new onset diabetes mellitus, requirement for antihypertensives, and requirement for cholesterol medications were similar between the groups. Annual calcineurin inhibitor costs were lower in the C2 arm ($5432 +/- 2091 for C2 versus $8291 +/- 3948 for FK, P = 0.001). Annual pretransplant drug costs ($2292 +/- 2331 for C2 versus $2831 +/- 2358 for FK, P = NS) and 1-year posttransplant drug costs ($17,214 +/- 16,600 for C2 versus $15,151 +/- 11,699 for FK, P = NS) were similar. In conclusion, immunosuppression with CsA, monitored by C2 levels, is safe, effective, and economical in liver transplant recipients and provides immunosuppression at least equivalent to that of FK.

Utility of C-2 (Cyclosporine) monitoring in postrenal transplant patients: A study in the Indian population

The study was planned and conducted to assess the benefit of C-2 levels (blood cyclosporine levels two hours postdosing) monitoring over trough (C0) levels (predosing) in postrenal transplant patients. The patient population included 34 postrenal transplant individuals (28 males and six females, mean age of 39.9 ± 12.3 years). The patients were first-transplant patients and were receiving a microemulsion form of cyclosporine A (CsA) as an immunosuppressant along with azathioprine and prednisolone. In addition, they were not on any enzyme inducer/inhibitor drugs, except for diltiazem. Timed collection of C0 and C-2 samples was done and the samples were immediately processed using the cedia cyclosporine plus assay kit. Estimation was done on a Beckman synchron CX5CE fully automated chemistry analyzer. Serum urea nitrogen and creatinine levels were checked. Poor graft survival was found in this population with 29.3% patients showing graft rejection. The graft rejection patients were assigned to two groups: group I with chronic graft rejection patients (17.6%) and group II with acute graft rejection patients (11.7%). Group III consisted of graft survival patients (70.7%). Mean ± SD was calculated for C0 and C2 levels. Individual values for C0 and C-2 were plotted on a scatter chart. C0 and C-2 levels were normalized by calculating them as the percentage of their targets (data not shown) and compared using the Kruskal Wallis one-way analysis of variance. C0 levels in all the three groups were within the recommended therapeutic range (150–300 ng/mL) (P < 0.182). Blood C-2 concentrations did not achieve the recommended target levels in these patients. One-way analysis of variance for C-2 values when expressed as the percentage of the target values did not show any significant difference between these groups (P < 0.84). No significant difference was found in C0 levels between groups I, II, and group III patients when expressed as the percentage of the target values (P < 0.182). The mean serum urea nitrogen level was 26.4 ± 8.1 mg/dL whereas the mean serum creatinine level was 1.79 ± 0.8 mg/dL. As is evident in the present study, the target C2 levels of cyclosporine dosage were not achieved whereas the C0 levels in all the three groups were within the optimum therapeutic range. As the incidence of graft dysfunction was also proportionately high, the importance of C2 monitoring is further highlighted on the basis of this study The contributory factors for levels lower than the target levels, such as the use of low doses of cyclosporine and interacting drugs should be carefully monitored in clinical practice. The achievement of optimum levels of C-2 may help in reducing the higher incidence of graft rejection in these patients. This practice is of equal importance in reducing cyclosporine-related renal toxicity, a rather irreversible process.

Monitoring of Blood Cyclosporine Concentration in Steroid-Resistant Nephrotic Syndrome

Cyclosporine has been used for patients with nephrotic syndrome. Because of substantial inter- and intra-patient variability and a narrow therapeutic window, drug monitoring of cyclosporine is mandatory. To confirm the therapeutic effects of a cyclosporine microemulsion (CSAME), the absorption profile of the agent after preprandial administration was determined in steroid-resistant patients with refractory nephrotic syndrome. Fourteen patients were enrolled into the study (mean age, 31.2+/-12; 6 men, 8 women). The patients received 1.5 mg/kg of cyclosporine 30 minutes before breakfast for 6 months. Blood cyclosporine concentration was measured 5 times serially: before administration (C0) and at 1-hour intervals until 4 hours after administration of cyclosporine (C1-C4). In addition, area under the concentration-time curve from 0-4 hours (AUC0-4) was calculated. After 6 months, CSAME showed marked improvement in proteinuria levels (8.3+/-4.8 g/day vs 0.8+/-0.4 g/day, p<0.001). No changes in serum creatinine and urea nitrogen levels were observed. In 83% of the patients, the CSAME peak concentration appeared within 1 hour after administration (C1). A strong positive correlation was noted between AUC0-4 and C1 (R2=0.90312) and C2 (R2=0.78431). The mean steroid (prednisolone) dose was 40 mg/day when CSAME treatment was started, but a lowering of the dose to 17.5 mg/day (p<0.001) was achieved at 6 months after CSAME therapy. Preprandial administration of CSAME is effective in steroid-resistant patients with refractory nephrotic syndrome. C1 or C2, but not C0, was a good clinical marker for CSAME exposure.

Cyclosporine Monitoring in Peripheral Blood Mononuclear Cells: Feasibility and Interest. A Prospective Study on 20 Renal Transplant Recipients

Cyclosporine (CsA) has potent immunosuppressive properties, reflecting its ability to block the transcription of cytokine genes (mainly interleukin 2) in CD4 + T lymphocytes, markedly improving transplantation outcomes in the past 20 years. CsA pharmacokinetic variability and renal toxicity require whole blood (WB) monitoring by 4-hour area under the drug concentration curves (AUC 0–4) or 2-hour postdose concentration (C 2) monitoring. Nevertheless, graft rejection can occur despite target blood levels, suggesting that WB monitoring does not guarantee optimal immunosuppression. For a decade, pharmacologists and clinicians have worked to optimize CsA doses; some authors, inspired by its mechanism of action, have proposed therapeutic drug monitoring using peripheral blood mononuclear cells (PBMC; lymphocytes and monocytes). The aim of this study was to assess the feasibility and interest of CsA monitoring in PBMC ([CsA] PBMC). We also measured in vitro distribution of CsA in CD4 + and CD4 − subsets.

Individualized population pharmacokinetic model with limited sampling for cyclosporine monitoring after liver transplantation in clinical practice

We recently developed and validated limited sampling models (LSMs) for cyclosporine monitoring after orthotopic liver transplantation based on individualized population pharmacokinetic models with Bayesian modelling. Aim To evaluate LSM in practice, and to seek optimal balance between benefit and discomfort. In 30 stable patients, more than 6 months after orthotopic liver transplantation, previously switched from trough- to 2 h post-dose (C2)-monitoring, we switched to 3-monthly LSM 0,1,2,3 h-monitoring. During 18 months we evaluated dose, creatinine clearance, calculated area under the curve, intra-patient pharmacokinetic variability and ability to assess systemic exposure by several previously validated LSMs. Within patients, there was variability of cyclosporine-area under the curve with the same dose (CV of 15%). Compared to C2-monitoring, there was no significant difference in dose (P = 0.237), creatinine clearance (P = 0.071) and number of rejections. Some models showed excellent correlation and precision with LSM 0,1,2,3 h comparing area under the curves (0,2 h: r(2) = 0.88; 0,1,3 h: r(2) = 0.91; 0,2,3 h: r(2) = 0.92, all P < 0.001) with no difference in advised dose. The limited sampling model, with only trough- and 2-h sampling, yields excellent accuracy and assesses systemic exposure much better than C2 with less bias and greater precision. Considering the calculated intra-patient variability, more precision is redundant, so LSM 0,2 h seems the optimal way of cyclosporine-monitoring.

A Review of the Immunosuppressive Activity of Cyclosporine Metabolites:New Insights into an Old Issue

Cyclosporine A (CsA) is metabolized into a vast spectrum of metabolites. The potential immunosuppressive action of CsA's metabolites has been studied extensively in the early 1990's, with conflicting and inconclusive results. Since then, the pharmacological and clinical consensus guidelines recommend the use of specific monoclonal assays for measurement of CsA's concentrations thus avoiding metabolite interference. Nevertheless, clinical benefit or superiority of these assays was never convincingly demonstrated. We provide a review of the performed in vivo, in vitro and animal studies and their conclusions. During the last years, many transplantation centres have employed the C(2) monitoring of CsA (2 hours post-dose concentration). The metabolites / parent drug ratio two hours post dose is completely different from trough levels (predose concentration). Cyclosporine exerts its immunosuppressive action by inhibiting the enzyme calcineurin phosphatase (CaN). Currently, our laboratory, among others, is working on determination of the enzyme's inhibition and its potential use as a pharmacodynamic biomarker. Utilizing this novel pharmacodynamic approach, we have performed in vitro and in vivo studies investigating the immunosuppressive impact of CsA's metabolites on C2 monitoring and on various monitoring assays (mono-/polyclonal). Interestingly, even though we have estimated in vivo that the potential immunosuppressive action of metabolites is less than 10% of the parent drug, we have found assays that take metabolites into consideration to correlate stronger with calcineurin phosphatase inhibition. We believe that the old controversial issue of metabolite induced immunosuppressive action examined under the light of newer pharmacodynamic approaches is still intriguing. Instead of a priori neglecting CsA's metabolites maybe we should investigate the potential of utilizing them as an additional tool towards better therapeutic drug monitoring of cyclosporine.

Cyclosporine Monitoring

Cyclosporine is an important immunosuppressive agent in organ and bone marrow transplantation. The pharmacokinetics of cyclosporine are quite complex and are complicated by the availability of two assay systems that yield differing results. This article summarizes the views from two major solid organ transplant centers and one bone marrow transplant center on important cyclosporine monitoring questions. A general consensus exists in the four areas discussed that: (1) cyclosporine concentrations must be monitored due in part to the extreme variability in kinetics, (2) either blood or plasma can be used in monitoring programs, (3) the radioimmunoassay or high pressure liquid chromatography can be used in routine monitoring, and (4) the interpretation of cyclosporine concentrations must be performed in relation to patient variables that affect drug response and toxicity.

Cyclosporine monitoring in the early post-transplant period in pediatric liver transplant recipients

Monitoring of CsA blood levels two h post-dose (C2) has shown a higher correlation to drug exposure than monitoring of trough levels (C0) at least in adults, but initial doses and target blood levels of CsA have yet to be established in pediatric transplant patients. The objectives of the study were to describe the pharmacokinetics of CsA administered by NGT in the first days after transplantation and the dose of Sandimmun Neoral required to achieve minimum therapeutic range blood levels. This study included 20 pediatric liver transplant recipients (mean age of 3.2 yr) treated with CsA administered by NGT from day one post-transplant until they were able to ingest oral medication. The study was continued until one yr of post-transplant follow-up. Eight h pharmacokinetic profiles were performed on days one, three, and five post-transplant to determine the minimum dose required to achieve the therapeutic range. All children received an initial dose of 15 mg/kg/day of CsA by NGT. Mean CsA doses administered on days one, three, and five were 16.8, 29.5, and 36.5 mg/kg/day, respectively. Mean C0 levels of 119, 310, and 337 ng/mL and mean C2 levels of 213, 753, and 888 ng/mL were obtained. No correlation was found between C0 and C2 levels and the AUC(0-8 h). Intravenous administration of CsA was required in 55% of patients. The biopsy-confirmed acute rejection rate was 45%, with graft and patient survival rates of 95 and 100%, respectively. Poor absorption of CsA in small children requires a considerable increase in dose. CsA exposure cannot be estimated by single C0 or C2 determinations in the early post-transplant period.

566 C2 monitoring of cyclosporine in heart transplant patients offers no clinical benefit over C0 monitoring - Zurich single center experience

566 C2 monitoring of cyclosporine in heart transplant patients offers no clinical benefit over C0 monitoring - Zurich single center experience

Pharmacodynamic Monitoring of Cyclosporine A in Renal Allograft Recipients Shows a Quantitative Relationship Between Immunosuppression and the Occurrence of Recurrent Infections and Malignancies

At present it is unclear which dose and consecutive blood levels of cyclosporine A (CsA) are optimal with respect to immunosuppressive efficacy and drug specific side effects at the level of individual patients. Several pharmacodynamic measures of CsA effects have been proposed, but have not become clinical routine yet. Besides the lack of practicability, the biological relevance of these assays has not been determined so far. Residual expression of nuclear factor of activated T-cells (NFAT)-regulated genes two hours after drug intake was used as molecular pharmacodynamic marker to assess CsA effects on lymphocytes and correlated with the frequency of recurrent infections and malignancies in patients with five or more years of follow-up posttransplantation. Recurrent infectious complications were observed in 44% and malignancies in 20% of the 133 patients studied. Patients with a strong suppression of NFAT-regulated genes by CsA--as judged by a residual level of transcription of less than 15% after drug intake--develop more frequent infections (53% vs. 29%; P = 0.005) and malignancies (22% vs. 4%; P = 0.002). The lack of correlation between the incidence of these complications and CsA blood concentration might point to the interindividual differences in the sensitivity towards calcineurin inhibition. The data presented here reveal a clear relation between the frequency of infectious and malignant complications and the degree of suppression of NFAT-regulated genes by CsA in transplanted patients. Therefore, pharmacodynamic monitoring of CsA efficacy in transplanted patients might be a useful tool to adjust immunosuppressive therapy in individual patients.

Correlations between Calcineurin Phosphatase Inhibition and Cyclosporine Metabolites Concentrations in Kidney Transplant Recipients: Implications for Immunoassays

Cyclosporine exhibits a wide spectrum of metabolites that vary considerably in the extent to which they interfere with the various parent drug monitoring immunoassays. There is no consensus regarding the clinical significance of metabolites. Cyclosporine exerts its immunosuppressive action by inhibiting the enzyme calcineurin phosphatase. Determination of the enzyme's activity is one of the most promising pharmacodynamic markers. It is unknown how calcineurin phosphatase inhibition correlates with various cyclosporine monitoring assays and what is the potential impact of metabolites in this perspective? The aim of the present study was to determine the concentration of cyclosporine (by means of three different assay methods) and the four most significant metabolites (AM1, AM4N, AM9, and AM1C) in relation to calcineurin phosphatase inhibition. Twelve randomly selected cyclosporine-treated renal transplant patients were included in the study. Blood samples were drawn before, 1, 2, 3, 4, 6, 8, and 12 hr after oral intake of cyclosporine. Parent drug and metabolites were determined by liquid chromatography/tandem mass spectrometry (LC/MSMS). Additionally, cyclosporine concentration was determined by the enzyme multiplied immunoassay technique (EMIT) and by the polyclonal fluorescence polarization immunoassay (pFPIA). Calcineurin phosphatase activity was measured by its ability to dephosphorylate a previously phosphorylated 19-amino acid peptide. We found that calcineurin phosphatase inhibition correlates strongly with parent cyclosporine metabolites concentrations determined by all three assay methods. Determination methods that took metabolites into consideration exhibit stronger correlations with calcineurin phosphatase inhibition (sum of cyclosporin plus metabolites r=-0.93, LC/MSMS; pFPIA r=-0.94, P<or=0.001), compared with methods that measure exclusively the parent drug (EMIT: -0.84; LC/MS-MS: -0.81, P<or=0.05). Our results indicate that the immunosuppressive role of cyclosporines metabolites should not be considered valueless per se. Further research is required in order to verify the potential clinical importance of our observations.

Early Cyclosporine C0 and C2 Monitoring in De Novo Kidney Transplant Patients: A Prospective Randomized Single-Center Pilot Study

C2 monitoring of cyclosporine (CsA) has been promoted as improving the results of organ transplantation. No randomized, controlled studies in de novo kidney transplant recipients are available. Between June 2003 and August 2004, 160 consecutive cadaveric kidney recipients allocated to CsA, mycophenolate and steroids were randomized to either C0 or C2 monitoring of CsA for the first 3 weeks posttransplant. Both levels were measured, keeping the other level blinded until 3 weeks. Altogether, 1451 double measurements were done. The target C0 was 200-300 microg/L and C2 1500-2000 microg/L. From the fourth week on, only C0 monitoring was used. Median follow up time was 505 days. The overall 3-month rejection rate was 7.5% in Group C0 vs. 10.8% in Group C2 and the one-year graft survival rates were 92.5% vs. 94.6% (NS). Rate of delayed graft function was similar in the groups. Plasma creatinine tended to be higher in group C2 at 3 weeks, but not thereafter. During the first three weeks posttransplant, the mean CsA dose was 57%, mean C2 levels were 55%, and mean C0 levels were 98% higher in group C2 than in group C0 (P < 0.00001). This pilot study showed no advantages of C2 monitoring but led to significantly higher CsA doses and blood levels than C0 monitoring.

Large Within-Day Variation in Cyclosporine Absorption

With the recent focus of monitoring cyclosporine (CsA) therapy using measures of CsA absorption, it is important to understand published reports of diurnal variation in CsA exposure. In 10 renal transplant patients, CsA concentrations were measured 0, 1, 2, 3, and 4 h after both the morning and the evening doses and in a repeat session at least 1 wk later. Both area under the curve for the final 4 h after cyclosporine dose and cyclosporine concentrate 2 h after the cyclosporine dose were more than two-fold higher after the morning dose in both sessions. Because the morning levels were collected in a fasted condition and the evening ones in a fed condition, the study was extended to collect evening levels after fasting. The area under the curve for the final 4 h after cyclosporine dose and cyclosporine concentrate 2 h after the cyclosporine dose values observed now were comparable to the morning fasted values. That the large diurnal variation was due to variation in food consumption, as opposed to a biologic circadian rhythm affecting CsA absorption, has significant implications for therapeutic drug monitoring.

Differentiation of innovator versus generic cyclosporine via a drug interaction on sirolimus

Both sirolimus and cyclosporine are immunosuppressants used in a combined regimen after organ transplantation. When coadministered with the innovator formulation of cyclosporine, sirolimus blood levels increase 3.3-fold due to a pharmacokinetic interaction. We assessed this drug interaction for potential differences when the innovator formulation is replaced by a generic cyclosporine. In this randomized single-dose crossover study, 28 healthy subjects received 5 mg sirolimus oral solution with 250 mg cyclosporine soft gelatin capsules given as the innovator formulation (reference treatment) versus a generic formulation (test treatment). Sirolimus peak blood concentration (Cmax) and area under the concentration-time curve (AUC) were compared between test and reference treatments by standard bioequivalence testing. Sirolimus Cmax was significantly lower by 17% in the presence of generic versus innovator cyclosporine (p=0.0003) and failed bioequivalence criteria with a test/reference ratio of 0.83 (90% confidence interval, 0.77-0.90). Nearly half of the subjects (46%) had sirolimus Cmax changes which fell outside the bioequivalence window with individual Cmax decreases up to 52% and increases up to 39%. Sirolimus AUC was significantly lower by 11% in the presence of generic versus innovator cyclosporine (p=0.041) but satisfied average bioequivalence criteria with a test/reference ratio of 0.89 (0.83-0.95). Nonetheless, over a third of the subjects (43%) had sirolimus AUC changes outside the standard bioequivalence window with individual AUC decreases up to 39% and increases up to 42%. Switching between innovator and generic cyclosporine may have a clinically-relevant impact on coadministered sirolimus pharmacokinetics. If such a switch is initiated by the prescriber, follow-up therapeutic monitoring of both cyclosporine and sirolimus blood levels should be performed to guide dose adjustments as necessary. If the switch is made without consulting the prescriber, potentially significant changes in sirolimus exposure could go unnoticed by the clinician and patient.

F.149. Pharmacodynamic Monitoring of Cyclosporine By Suppression of Nfat Regulated Gene Expression in Peripheral Blood Cells of Cardiac Allograft Recipients On Standard and Reduced Dosage Regimens Allows Prediction of Infections

F.149. Pharmacodynamic Monitoring of Cyclosporine By Suppression of Nfat Regulated Gene Expression in Peripheral Blood Cells of Cardiac Allograft Recipients On Standard and Reduced Dosage Regimens Allows Prediction of Infections

Cyclosporine monitoring in renal transplant recipients with induction therapy: C2 levels in patients monitored on C0

The aim of this retrospective study was to compare the cyclosporine C(2) blood levels in renal transplant recipients with induction therapy, monitored on C(0) levels during the early and long-term post-transplantation periods in different French transplantation centres, to the target values recommended by the International Consensus on Neoral and used in the Mo2art study. A retrospective study was conducted by the therapeutic drug monitoring (TDM) committee of the French Pharmacological Society. Cyclosporine C(0) and C(2) concentrations from 168 renal transplant recipients were collected at different post-transplantation periods by six TDM laboratories of transplantation centres from April 2001 to April 2002. Cyclosporine blood levels were determined by fluorescence polarization immunoassay (mFPIA, AxSYM, Abbott) or enzyme immunoassay (EMIT, Dade Behring). Most patients had C(0) values in the recommended target ranges, with C(2) levels below the targets used in the Mo2art study or proposed by the International Consensus Conference, both during the early and long-term post-transplantation periods. Sixty-eight per cent of patients had C(2) below 1,500 microg/L +/- 20% in the first 2 months post-transplantation and 55% had C(2) below 800 microg/L +/- 20% in the late post-transplantation period (>1 year). Cyclosporine dose should be increased by 40% on average during the first week post-transplantation period and by 50% during the maintenance period to achieve the C(2) targets. In France, most renal transplant recipients receiving induction agents monitored on C(0) had C(2) levels below the targets recommended by the International Consensus Conference. In clinical practice, the optimal therapeutic windows for CsA monitoring based on C(2) needs to be more precisely defined, both during the early and long-term post-transplantation periods in renal transplant recipients receiving induction agents.

Daily Monitoring of Cyclosporine (Csa) Allows Better Control of Graft vs. Leukaemia Effect (GvL): Single Centre Experience.

The most important consideration in modern SCT practices is the fine balance that is required to achieve adequate immunosuppression and stable engraftment thus allowing the platform to mount an effective GVL response. Though CsA facilitates this objective, it is associated with several adverse clinical manifestations due to its narrow therapeutic index (TI) and wide variability in the absorption kinetics. Weekly monitoring of trough CsA levels are used to adjust the dose. The aim of this study is to determine whether daily monitoring of CsA levels enables better achievement of these goals and yet reduce the serious toxicities.Patients & methods: Twenty three patients (M=15, F=8, median age 46yrs range 19–63) received an allogeneic transplant (sibling-15, MUD-7 mismatched unrelated-1) since March 2004 when we started to monitor daily CsA levels (Biostat TDX analyser using fluorescent immunoassay) from the day of first administration until the time of discharge. The transplants included full intensity (FI=11), reduced intensity (RI=11) or customised (1) for various haematolymphoid malignancies. Patients received uniform GVHD prophylaxis with IV CsA (RI+FI) and methotrexate (FI) as per standard loading doses. The CsA target level was adjusted to 200–220 ng/ml from Day-1 onwards and was later modified according to the treatment strategy. Oral CsA administration was started when patients were able to switch over. Results Nine of 23 (40%) patients developed acute GVH (n=7 grade1–2, n=2 grade 3–4) at a median of 23.5 days (10–28). Two of 9 patients required addition of steroids by Day+30. The median CsA level at the first occurrence of GVH was 247ng/ml (113–333) and the median CsA level during hospitalisation was 207 ng/ml (136–291). Only one patient who received T cell addback required increased dose of IV CsA to manage Grade 4 GVH. Twenty two/22 patients engrafted with a median day to neutrophil recovery being 13 days (8–35). One patient lost his graft due to a low initial cell dose and the inability of the MUD donor to donate any further cells. There was no significant difference in the baseline and Day30 creatinine levels (median highest creatinine 108μmol/l range 58–267) or bilirubin levels (median highest bilirubin 27μmol/l, range15–251). Five/22 patients developed CMV reactivation/infection and 1 developed RSV infection. No patients developed seizures and in one patient pre-existent neuropathy was exacerbated which was directly attributable to CsA. Twenty one/22 patients (95.5%) switched to oral CsA by Day+25. In 8/22 (36.36%) patients, the target CsA levels was around 100–150 ng/ml at the time of discharge. The median duration of hospital stay was 35days (24–130).Conclusions: These observations suggests that daily monitoring of CsA is safe and successful. This allowed successful engraftment and a more liberal management of Grade 1–2 GVH thus allowing us to maximise the GVL effect. Despite concomitant use of other toxic drugs, side effects were minimal and reversible. Close observation of early clinical manifestations enabled us to modify the immunosuppressive strategy at later time periods. This approach also allowed us to better manage patients suffering from CMV and EBV/PTLD (patient number 10 on day+88) by reducing the dose during active infections.

A Randomized, Controlled Trial of C 0- Vs C 2-guided Therapeutic Drug Monitoring of Cyclosporine in Stable Heart Transplant Patients

Cyclosporine monitoring using 2-hour post-dose samples (C2) is thought to be more efficacious than using pre-dose levels (C0) in managing immunosuppression for transplant patients. We evaluated the effect of C2 monitoring on cyclosporine dose and clinical parameters in stable heart transplant patients. 125 stable heart transplant patients were randomized to C0 or C2 monitoring of cyclosporine levels for a period of six months. All patients had both C0 and C2 samples taken, and clinicians were blinded to one of the samples depending on randomization. The primary endpoint was the relative change in cyclosporine (Neoral) dose during the study period and secondary endpoints were change in creatine clearance, mortality, infection, and acute rejection. There was a significant decrease in the cyclosporine dose for the C2 group as compared with the C0 group (-11 mg/day and -26 mg/day respectively, p = 0.0025). No proven rejection episodes occurred in either group and there was no significant difference in the incidence of infection (C0 6, C2 10; p = 0.14), the change in renal function (change in creatine clearance C(0) +0.54 ml/min; C2 -0.16 ml/min; p = 0.61), the number of blood tests or dose adjustments between groups over the study period. Analysis of the blinded samples revealed that the reduction of cyclosporine dose in the C2 group could not be accounted for by reduced immunosuppression . C2 monitoring allows a significant cyclosporine dose reduction without compromising patient outcome in stable heart transplant patients. Further studies are required to ascertain whether this dose reduction can be translated into clinical benefit.

C1-C2 point monitoring of low-dose cyclosporin A given as a single daily dose in children with steroid-dependent relapsing nephrotic syndrome

It has been reported that the pharmacokinetics of cyclosporin A (CsA) in children is different from that in adults. It appears that, in general, pediatric patients metabolize CsA more rapidly than adult patients, necessitating the use of higher dose of the drug in pediatric transplant recipients. In this context, we speculated that single-dose daily administration of low-dose CsA may be associated with a higher peak blood level without associated trough blood level elevation, and thereby yield better results and allow safer use of the drug than the conventional twice daily administration dosing used for the treatment of childhood idiopathic nephrotic syndrome (INS). A total of 10 children with steroid-dependent relapsing INS (9 with biopsy-proven minimal-change disease) who showed steroid toxicity were enrolled in the study. The initial daily dose of CsA (Neoral) used was around 2.0 mg/kg, given as a single daily dose before breakfast. The dose was subsequently adjusted to achieve a C1-C2 point blood level between 600 - 800 ng/ml. The dose of the concomitantly administered prednisolone was tapered following the commencement of CsA. The mean daily CsA dosage, the mean C1-C2 point blood level and the mean trough blood level in the subjects were 2.2 +/- 0.8 mg/kg, 754.0 +/- 71.9 ng/ml and 42.7 +/- 29.2 ng/ml, respectively. At the latest observation, after a mean duration of 17 months (6 - 24 months) of CsA therapy, the minimum dose of prednisolone required for maintenance of clinical remission and the calculated relapse rate were significantly decreased as compared to the respective pretreatment values (0.52 +/- 0.46 mg/kg on alternate days, vs. 0.97 +/- 0.63 mg/kg on alternate days, and 0.28 +/- 0.32 times per six months, vs. 1.06 +/- 0.41 times per six months, respectively, p = 0.005). No significant change was observed in the mean estimated GFR value as compared to the pretreatment value (183.1 +/- 35.4 ml/min/1.73 m2vs. 185.4 +/- 39.3 ml/min/1.73 m2). No evidence of CsA nephrotoxicity was observed in a repeat renal biopsy performed around 12 months after the commencement of CsA therapy in two patients. Despite the limitations of the study, our results suggest that administration of low-dose CsA as a single daily dose with C1-C2 point blood level monitoring might be an equally effective and safe and, therefore, more cost-beneficial, protocol for the treatment of steroid-dependent cases of relapsing INS, as conventional twice-daily administration of CsA with trough blood level monitoring. Further studies to confirm the long-term efficacy and safety of this CsA treatment protocol in larger numbers of patients are, however, needed.