Biomedical subjects

Alexander Korn

Publications and source records attributed to Alexander Korn.

7 recordsLinked to original sources

PubMed2003

Early prognosis of the development of renal chronic allograft rejection by gene expression profiling of human protocol biopsies.

BACKGROUND: Chronic allograft rejection (CR) is the major cause of failure of long-term graft survival and is so far irreversible. Early prognosis of CR by molecular markers before overt histologic manifestation would be a valuable aid for the optimization of treatment regimens and the design of clinical CR trials. Oligonucleotide microarray-based approaches have proven to be useful for the diagnosis and prognosis of a variety of diseases and were chosen for the unbiased identification of prognostic biomarkers. METHODS: Renal allograft biopsies were taken at month 6 posttransplantation (PT) from two groups who were, at that time, healthy recipients: one group developed CR at month-12 PT, the other group remained healthy. Gene expression profiles from the two groups at month-6 PT biopsies were analyzed to identify differentially expressed genes with prognostic value for CR development at month 12. RESULTS: A set of 10 genes was identified that showed differential expression profiles between the two patient groups and had a complete separation of the 15% to 85% quantile range for each individual gene. This set of genes was sufficient to allow the correct prediction of the occurrence or nonoccurrence of CR in 15 of 17 (88%) patients using cross-validation (occurrence for a patient was predicted on the basis of the other patients' data only). In addition, a correct prediction could be made that a recipient with a normal biopsy 12 months PT developed CR within the following 6 months. CONCLUSIONS: Identified expression patterns seem to be highly prognostic of the development of renal CR.

Adult↗

PubMed2003

Randomized double-blind study of immunoprophylaxis with basiliximab, a chimeric anti-interleukin-2 receptor monoclonal antibody, in combination with mycophenolate mofetil-containing triple therapy in renal transplantation.

BACKGROUND: Acute rejection remains a major problem in renal transplantation. Immunoprophylaxis with basiliximab (Simulect) has achieved significant reductions in acute rejection episodes in renal allograft recipients receiving dual immunosuppression. This study explored the tolerability and cumulative benefit of combining basiliximab with triple-drug therapy-cyclosporine (USP Modified, Neoral), mycophenolate mofetil, and steroids. METHODS: In a randomized, double-blind, placebo-controlled, multicenter study, 123 kidney transplant recipients received either basiliximab at 20 mg before transplantation (day 0) and 20 mg on day 4 (n=59), or placebo (n=64). All received triple-drug immunosuppression and were followed for 6 months. RESULTS: Tolerability of basiliximab was equivalent to placebo, with no increase in serious adverse events, infection, malignancy, or posttransplant lymphoproliferative disorder. At 6 months, there were trends in favor of basiliximab over placebo in the incidences of first biopsy-confirmed acute rejection (15.3% vs. 26.6%, P=NS) and of acute rejection treated with antibody (5.1% vs. 15.6%, P=NS). Kaplan-Meier estimates at 4 weeks and 6 months were significantly in favor of basiliximab treatment for first acute rejection, biopsy-confirmed rejection, rejection episodes treated with antibody therapy, and treatment failure. Renal function improved more rapidly in the basiliximab group, with mean creatinine clearance at week 2 being 54.7 mL/min versus 43.2 mL/min for placebo (P=0.034). At 12 months, patient survival was 100% in both groups; graft survival was 94.9% with basiliximab and 92.2% with placebo. CONCLUSIONS: Basiliximab immunoprophylaxis is safe, well tolerated, and shows a trend toward reduction in number of acute rejection episodes in renal transplant patients receiving cyclosporine, mycophenolate mofetil, and steroids.

Adult↗

PubMed2002

Safety and efficacy of an alternative basiliximab (Simulect) regimen after renal transplantation: administration of a single 40-mg dose on the first postoperative day in patients receiving triple therapy with azathioprine.

This was a multi-center, open-label, randomized, dose-comparative study on 202 renal transplantation patients. We evaluated for the first time an alternative dosing regimen for basiliximab, consisting of a single 40-mg intravenous dose on day 1 post-transplantation plus triple therapy, in comparison with the conventional two-dose regimen (2 h before transplantation and on day 4) plus triple therapy. At 6 months, the incidence of acute rejection was low: 22.5% of patients in the basiliximab 2 x 20-mg group and 20.0% of patients in the basiliximab 1 x 40-mg group experienced an acute rejection episode ( P = 0.628) (biopsy-proven rejection: 19.6% and 17.0%, P = 0.585). There was no statistically significant difference in any of the secondary efficacy parameters. The incidence of graft loss by 12 months was 4.9% and 6.0% in the 2 x 20-mg and 1 x 40-mg group, respectively ( P = 0.73). No differences were observed between the dosage groups with regards to safety assessments (adverse events (AEs), infections, vital signs, laboratory safety evaluations, and physical examinations). The data reveal that basiliximab can be safely and effectively administered as a single 40-mg dose on day 1 after renal transplantation as a therapeutic option to the established 2 x 20-mg dosing regimen. This alternative dosing regimen may be of significant convenience under circumstances when a first dose of basiliximab was not given prior to transplantation. Both regimens can conveniently be used during the initial hospitalization of the patient.

Acute Disease↗

PubMed2002

A multicenter, open-label, pharmacokinetic/pharmacodynamic safety, and tolerability study of basiliximab (Simulect) in pediatric de novo renal transplant recipients.

BACKGROUND: Basiliximab (Simulect) has been shown to be safe and effective in adult renal transplant recipients, when used in combination with cyclosporine (Neoral) and corticosteroids. We report on the safety and preliminary efficacy of basiliximab in pediatric de novo renal transplant recipients. METHODS: This was an open-label, 12-month study of basiliximab in 41 patients (2 cohorts: <9 and 9 to <16 years). In phase 1, two intravenous (IV) bolus injections of basiliximab (12 mg/m ) were administered (before and 4 days postsurgery). In phase 2, two injections (<40 kg, 10 mg and > or =40 kg, 20 mg) were administered at the same time points. Most patients (26/41 [63%]) received cadaveric kidneys. Almost half of the patients had three human leukocyte antigen mismatches with the organ donors. Concurrent immunosuppression included Neoral and corticosteroids. Azathioprine was allowed after 28 days. RESULTS: All patients completed the 1-year study. The acute tolerability of basiliximab via IV bolus injection was good, without evidence of cytokine-release syndrome or acute local reactions. All patients experienced adverse events, but most (71%) were mild or asymptomatic. No deaths or malignancies occurred. The incidence and types of serious adverse events (59%) and serious infections (44%) were as expected in this patient population, and few were drug-related (7% and 5%, respectively). Thirty-eight patients (93%) had infections, mostly urinary tract infections, as expected for renal transplant patients. Six patients (15%) had drug-related adverse events. Biopsy-confirmed acute rejection episodes occurred in 6/41 (15%) of patients during the first 6 months posttransplantation and in 9/41 (22%) patients during the first 12 months. Five patients (12%) experienced graft loss, none of which were preceded by acute rejection episodes. CONCLUSIONS: Basiliximab is safe and well tolerated when administered by IV bolus injection in de novo pediatric renal transplant recipients. These preliminary data suggest that basiliximab, given in combination with cyclosporine and corticosteroids, is an effective immunosuppressive regimen for the prevention of acute rejection in pediatric renal transplantation.

Adolescent↗

PubMed2002

A rational dosing algorithm for basiliximab (Simulect) in pediatric renal transplantation based on pharmacokinetic-dynamic evaluations.

BACKGROUND: The pharmacokinetics and immunodynamics of basiliximab were assessed in 39 pediatric de novo kidney allograft recipients to rationally chose a dose regimen for this age group. METHODS: In study part 1, patients were given 12 mg/m(2) of basiliximab by bolus intravenous injection before surgery and on day 4. An interim pharmacokinetic evaluation supported a fixed-dose approach for study part 2 in which infants and children received two 10-mg doses and adolescents received two 20-mg doses. Blood samples were collected over a 12-week period for analysis of basiliximab and soluble interleukin-2 receptor concentrations, flow cytometry, and screening for anti-idiotype antibodies. RESULTS: Basiliximab clearance in infants and children (n=25) was reduced by approximately half compared with adults from a previous study and was independent of age (1-11 years), weight (9-37 kg), and body surface area (0.44-1.20 m(2) ). Clearance in adolescents (12-16 years, n=14) approached or reached adult values. CD25-saturating basiliximab concentrations were maintained for 31+/-12 days in study part 1 with mg/m(2) dosing and for 36+/-14 days in study part 2 based on the fixed-dose regimen ( P=0.31). A single patient experienced a rejection episode during CD25 saturation. The duration of CD25 saturation in patients who experienced a rejection episode after desaturation did not differ from those who remained rejection-free for the full 6-month period: 34+/-6 days (n=6) vs. 35+/-14 days (n=33 patients); P=0.74. Anti-idiotype antibodies were detected in two patients; however, this did not influence the clearance of basiliximab or the duration of CD25 saturation. CONCLUSIONS: To achieve similar basiliximab exposure as is efficacious in adults, pediatric patients <35 kg should receive two 10-mg doses and those > or =35 kg should receive two 20-mg doses of basiliximab by intravenous infusion or bolus injection. The first dose is given before surgery and the second on day 4 after transplantation.

Algorithms↗

PubMed2002

Basiliximab in pediatric liver transplantation: a pharmacokinetic-derived dosing algorithm.

The pharmacokinetics and immunodynamics of basiliximab were assessed in 37 pediatric de novo liver allograft recipients to rationally design a dose regimen for this age-group. In part one of the study, patients were given 12 mg/m2 basiliximab by bolus intravenous injection after organ perfusion and on day 4 after transplant. An interim pharmacokinetic evaluation supported a fixed-dose approach for part two of the study in which infants and children received two 10-mg doses of basiliximab and adolescents received two 20-mg doses. Blood samples were collected over a 12-week period for screening for anti-idiotype antibodies and analysis of basiliximab and soluble interleukin-2 receptor (IL-2R) concentrations. Basiliximab clearance in infants and children < 9 yr of age (n = 30) was reduced by approximately 50% compared with adults from a previous study and was independent of age to 9 yr, weight to 30 kg, and body surface area to 1.0 m2. Clearance in children and adolescents 9-14 yr of age (n = 7) approached or reached adult values. An average of 15% of the dose was eliminated via drained ascites fluid, and drug clearance via this route averaged 29% of total body clearance. Patients with > 5 L of ascites fluid drainage tended to have lower systemic exposure to basiliximab. CD25-saturating basiliximab concentrations were maintained for 27 +/- 9 days in part one of the study (mg/m2 dosing) with infants exhibiting the lowest durations. CD25 saturation lasted 37 +/- 11 days in part two of the study, based on the fixed-dose regimen (p = 0.004 vs. mg/mg2 dosing), but did not show the age-related bias observed in part one of the study. Anti-idiotype antibodies were detected in four patients, but this did not influence the clearance of basiliximab or duration of CD25 saturation. All 40 enrolled patients were included in the intent-to-treat clinical analysis. Episodes of acute rejection occurred in 22 patients (55%) during the first 12 months post-transplant. Three patients experienced loss of their graft as a result of technical complications, and six patients died during the 12-month study. Basiliximab was well tolerated by intravenous bolus injection, with no cytokine-release syndrome or other infusion-related adverse events. Hence, basiliximab was safe and well tolerated in pediatric patients undergoing orthotopic liver transplantation. To achieve similar basiliximab exposure as is efficacious in adults, pediatric patients < 35 kg in weight should receive two 10-mg doses and those > or = 35 kg should receive two 20-mg doses of basiliximab by intravenous infusion or bolus injection. The first dose should be given within 6 h after organ perfusion and the second on day 4 after transplantation. A supplemental dose may be considered for patients with a large volume of drained ascites fluid relative to body size.

Adolescent↗

PubMed2002

Improved treatment response with basiliximab immunoprophylaxis after liver transplantation: results from a double-blind randomized placebo-controlled trial.

Basiliximab, a high-affinity chimeric monoclonal antibody, is effective in reducing acute rejection episodes in renal allograft recipients. We assessed the ability of this antibody to similarly improve the outcome in liver transplant recipients. Adult recipients of a primary cadaveric liver transplant were randomized to treatment, stratified by hepatitis C virus (HCV) seropositivity. Patients were administered 40 mg of basiliximab (n = 188) or placebo (n = 193) as two 20-mg bolus injections days 0 and 4, plus cyclosporine and steroids. Primary efficacy variables were biopsy-confirmed acute rejection and its composite end point, including death or graft loss, and were assessed at 6 and 12 months and by HCV cohort. Because of differential efficacy responses between HCV-positive and HCV-negative cohorts, an additional analysis incorporating HCV recurrence as a component of treatment failure, termed problem-free transplant, was introduced. Safety and tolerability were monitored over the 12 months of the study. All 381 patients were assessable, and no meaningful differences in background characteristics were apparent between treatment groups. Biopsy-confirmed acute rejection rates 6 months after transplantation were 35.1% in the basiliximab group versus 43.5% in the placebo group. For death, graft loss, or first biopsy-confirmed acute rejection, rates were 44.1% versus 52.8%, respectively. The reduction in rejection episodes was concentrated in the HCV-negative cohort (14.5% relative to placebo; P =.034), with a much smaller difference (2.9%) in the HCV-positive cohort. For HCV-positive patients, problem-free transplant was shown at 12 months in 26.6% of the basiliximab group versus 11.6% in the placebo group (P =.020) and for all patients at 12 months in 39.7% of the basiliximab group versus 30.1% in the placebo group (P =.035). The incidence of infection and other adverse events was similar across the two treatment groups. There were 56 deaths (25 deaths, basiliximab group; 31 deaths, placebo group) over the 12-month study. The intravenous bolus injection was well tolerated. Immunoprophylaxis with 40 mg of basiliximab, in combination with cyclosporine and steroids, reduces the incidence of acute rejection episodes with no clinically relevant safety or tolerability concerns. The influence of HCV recurrence on efficacy results can be accounted for in future trials by using the concept of problem-free transplant, incorporating recurrence as a component of treatment failure.

Adult↗