High melphalan exposure is associated with improved overall survival in myeloma patients receiving high dose melphalan and autologous transplantation.

Aim: High dose melphalan (HDM) and autologous stem cell transplantation (ASCT) retains a central role in the treatment of myeloma. The aim of this study was to determine whether HDM exposure (area under the concentration vs. time curve, AUC), is significantly associated with transplant outcomes.

Development and Validation of a High Pressure Liquid Chromatography-UV Method for the Determination of Treosulfan and Its Epoxy Metabolites in Human Plasma and Its Application in Pharmacokinetic Studies.

Treosulfan (l-threitol-1,4-di-methanesulfonate) is a prodrug of a bifunctional alkylating agent that is being used increasingly in pediatric bone marrow transplantation regimens. The activation pathway is a complex reaction, which consists of two consecutive reactions leading to epoxybutane derivatives which are responsible for DNA alkylation. A simple, sensitive high performance liquid chromatography method for the determination of the sum of treosulfan and its epoxy metabolites by UV detection after derivatization with sodium diethyldithiocarbamate in human plasma was developed and validated.

Population pharmacokinetics of mycophenolic acid in children and young people undergoing blood or marrow and solid organ transplantation.

Aims: To characterize the population pharmacokinetics of mycophenolic acid (MPA) and evaluate dose regimens using a simulation approach and accepted therapeutic drug monitoring targets in children and young people undergoing blood or marrow, kidney and liver transplantation.

Methods: MPA concentration-time data were collected using an age specific sampling protocol over 12h. Some patients provided randomly timed but accurately recorded blood samples.

An isocratic fluorescence HPLC assay for the monitoring of l-asparaginase activity and l-asparagine depletion in children receiving E. colil-asparaginase for the treatment of acute lymphoblastic leukaemia.

A novel assay for the determination of l-asparaginase activity in human plasma is described that is based on the HPLC quantitation of l-aspartic acid produced during enzyme incubation. Methods for monitoring l-asparagine depletion are also described. Chromatography of l-aspartic acid, l-asparagine and l-homoserine (the internal standard) involved derivatization with o-pthaldialdehyde, then separation from other amino acids on a Phenomenex Luna C(18) column using a 1 mL/min flow rate and a mobile phase consisting of di-potassium hydrogen orthophosphate propionate buffer, pH 6, with 10% methanol and 10% acetonitrile.

Variability in the pharmacokinetics of intravenous busulphan given as a single daily dose to paediatric blood or marrow transplant recipients.

Aim: To examine inter- and intrapatient variability in the pharmacokinetics of intravenous (i.v.) busulphan given as a single daily dose to children with malignant (n = 19) and nonmalignant (n = 21) disease.

Population pharmacokinetics of melphalan in paediatric blood or marrow transplant recipients.

Aim: To develop a population pharmacokinetic model for melphalan in children with malignant diseases and to evaluate limited sampling strategies for melphalan.

Methods: Melphalan concentration data following a single intravenous dose were collected from 59 children with malignant diseases aged between 0.3 and 18 years.

Amphotericin B dose optimization in children with malignant diseases.

In this study, rational dosing guidelines for amphotericin B-deoxycholate (AmB) are proposed for children. AmB steady-state trough concentrations (C(ss,trough)) and plasma creatinine concentrations (C(creat)) were measured in 83 children (age: 10 months to 18 years) receiving prophylactic AmB therapy (1 mg/kg/day). Maximum tolerable AmB C(ss,trough) were identified by determining the probability of large (>24%, 75th percentile) increases in C(creat) after 6 days of AmB for a series of C(ss,trough) ranges.

Plasma protein distribution and its impact on pharmacokinetics of liposomal amphotericin B in paediatric patients with malignant diseases.

Objective: This study investigates the association of liposomal amphotericin B (L-AmB) with plasma proteins and its impact on the pharmacokinetics of L-AmB in paediatric patients with malignant diseases.

Methods: Paediatric oncology patients (n = 39) who received multiple-doses of L-AmB were recruited into this study. The association of the drug with plasma lipoprotein was investigated using single vertical spin density gradient ultracentrifugation and quantitated with a validated HPLC assay.

Population pharmacokinetics of liposomal amphotericin B in pediatric patients with malignant diseases.

A population pharmacokinetic model of liposomal amphotericin B (L-AmB) in pediatric patients with malignant diseases was developed and evaluated. Blood samples were collected from 39 pediatric oncology patients who received multiple doses of L-AmB with a dose range from 0.8 to 5.

Melphalan pharmacokinetics in children with malignant disease: influence of body weight, renal function, carboplatin therapy and total body irradiation.

Aim: To analyse the pharmacokinetics of melphalan in 52 children (0.3-18 years) and determine whether any clinical factors affect the pharmacokinetic parameters Additionally, to examine whether a test melphalan dose can predict the pharmacokinetics of a full dose, when there are 5 intervening days of carboplatin therapy.

Methods: Melphalan concentrations were measured in 14 blood samples collected from each child following doses ranging from 30 to 180 mg m(-2).

HeLa cells cocultured with peripheral blood lymphocytes acquire an immuno-inhibitory phenotype through up-regulation of indoleamine 2,3-dioxygenase activity.

The mechanisms by which tumour cells escape recognition by the immune system or subvert antitumour effector responses remain poorly understood. In the course of investigating the potential of costimulatory signals in anticancer immunotherapy strategies, we have observed that HeLa cells (a human cervical carcinoma cell line) cocultured with peripheral blood lymphocytes (PBL) acquire the capacity to inhibit PBL proliferation in response to interleukin-2 (IL-2). This immuno-inhibitory phenotype was further shown to result from induction of the tryptophan-catabolizing enzyme, indoleamine 2,3-dioxygenase (IDO), by interferon-gamma (IFN-gamma) secreted from cocultured allo-reactive PBL.