Dataset Information

A population pharmacokinetic model of AT9283 in adults and children to predict the maximum tolerated dose in children with leukaemia.

ABSTRACT: AIMS:AT9283 is used to treat patients with solid tumours and patients with leukaemia. However, the maximum tolerated dose (MTD) for children with leukaemia remains unknown due to early termination of the Phase I trial. The aim of this study was to develop a population model of AT9283 to describe the pharmacokinetics in adults and children and to estimate the MTD in children with leukaemia. METHODS:Data from Phase I dose-escalation studies in adults and children were used to build a population pharmacokinetic model (NONMEM v7.3). Potential covariates investigated included body weight, body surface area (BSA), glomerular filtration rate (GFR), age and sex. Model-derived area under the concentration-time curve was used to investigate the relationship between dose and exposure in adults and children. RESULTS:The plasma concentrations of AT9283 (n = 1770) from 92 patients (53 adults, 39 children) were used to build a two-compartment model with all pharmacokinetic parameters scaled using body weight. Renal function (GFR), but not BSA, was a significant covariate for the clearance of AT9283. In children with leukaemia (median weight 16 kg), a flat dose of 500 mg 72 h-1 provided similar drug exposures at the MTD as the adult population. The estimated MTD for children with leukaemia, therefore, is 30 mg kg-1 72 h-1 . CONCLUSION:For adults, GFR was a significant predictor of clearance, whilst body-weight based dosing was more useful than BSA in determining the drug exposure in children. The MTD was estimated to be 30 mg kg-1 72 h-1 children with leukaemia.

SUBMITTER: Duong JK

PROVIDER: S-EPMC5510070 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A population pharmacokinetic model of AT9283 in adults and children to predict the maximum tolerated dose in children with leukaemia.

Duong Janna K JK Griffin Melanie J MJ Hargrave Darren D Vormoor Josef J Edwards David D Boddy Alan V AV

British journal of clinical pharmacology 20170305 8

<h4>Aims</h4>AT9283 is used to treat patients with solid tumours and patients with leukaemia. However, the maximum tolerated dose (MTD) for children with leukaemia remains unknown due to early termination of the Phase I trial. The aim of this study was to develop a population model of AT9283 to describe the pharmacokinetics in adults and children and to estimate the MTD in children with leukaemia.<h4>Methods</h4>Data from Phase I dose-escalation studies in adults and children were used to build ...[more]

PMID: 28177130

Similar Datasets

Project description:BackgroundTargeted agents, such as antiangiogenic drugs (e.g., bevacizumab) and poly(ADP-ribose) polymerase inhibitors (e.g., rucaparib), have been shown to improve outcomes in patients with newly diagnosed or recurrent ovarian cancer. Evidence suggests that combinations of these two classes of targeted agents may result in synergistic antitumor activity.ObjectiveThe phase I portion of MITO 25 was designed to determine the maximum tolerated dose, pharmacokinetics, and the safety profile of rucaparib when administered in combination with bevacizumab as maintenance treatment for patients with high-grade epithelial ovarian, fallopian tube, or primary peritoneal cancer.MethodsThis was a single-arm, phase I dose-escalation study. Cohorts of three patients were recruited to receive increasing rucaparib doses of 400 mg, 500 mg, or 600 mg twice daily for 28 days. Bevacizumab 15 mg/kg was administered at day 1 every 21 days.ResultsWe enrolled nine patients. Two patients in the rucaparib 600-mg group had four grade 3 treatment-emergent adverse events: increased in alanine aminotransferase and aspartate aminotransferase levels, depression, and hallucinations. These were deemed to be dose-limiting toxicities related to rucaparib. Because these dose-limiting toxicities occurred in the 600-mg group and affected more than one in three patients, the maximum tolerated dose for rucaparib was considered 500 mg twice daily when combined with bevacizumab 15 mg/kg at day 1 every 21 days. There were no new safety concerns from using the combination. No substantial difference in pharmacokinetic parameters was found between the cohorts or in the pharmacokinetic profiles of rucaparib administered alone or with bevacizumab with respect to historical controls.ConclusionsThe maximum tolerated dose of rucaparib is 500 mg twice daily when co-administered with bevacizumab. The plasma concentration-time profiles of rucaparib in combination with bevacizumab suggest no pharmacokinetic interactions between the drugs. The randomized phase II portion of MITO 25 will further investigate rucaparib maintenance treatment with or without bevacizumab in patients with newly diagnosed stage III-IV ovarian cancer who responded to carboplatin-paclitaxel chemotherapy with or without bevacizumab.Trial registrationClinicalTrials.gov identifier NCT03462212; registered March 2018.

Project description:Background. Absent adaptive, individualized dose-finding in early-phase oncology trials, subsequent 'confirmatory' Phase III trials risk suboptimal dosing, with resulting loss of statistical power and reduced probability of technical success for the investigational therapy. While progress has been made toward explicitly adaptive dose-finding and quantitative modeling of dose-response relationships, most such work continues to be organized around a concept of 'the' maximum tolerated dose (MTD). The purpose of this paper is to demonstrate concretely how the aim of early-phase trials might be conceived, not as 'dose-finding', but as dose titration algorithm (DTA)-finding. Methods. A Phase I dosing study is simulated, for a notional cytotoxic chemotherapy drug, with neutropenia constituting the critical dose-limiting toxicity. The drug's population pharmacokinetics and myelosuppression dynamics are simulated using published parameter estimates for docetaxel. The amenability of this model to linearization is explored empirically. The properties of a simple DTA targeting neutrophil nadir of 500 cells/mm 3 using a Newton-Raphson heuristic are explored through simulation in 25 simulated study subjects. Results. Individual-level myelosuppression dynamics in the simulation model approximately linearize under simple transformations of neutrophil concentration and drug dose. The simulated dose titration exhibits largely satisfactory convergence, with great variance in individualized optimal dosing. Some titration courses exhibit overshooting. Conclusions. The large inter-individual variability in simulated optimal dosing underscores the need to replace 'the' MTD with an individualized concept of MTD i . To illustrate this principle, the simplest possible DTA capable of realizing such a concept is demonstrated. Qualitative phenomena observed in this demonstration support discussion of the notion of tuning such algorithms. Although here illustrated specifically in relation to cytotoxic chemotherapy, the DTAT principle appears similarly applicable to Phase I studies of cancer immunotherapy and molecularly targeted agents.

Dataset Information

A population pharmacokinetic model of AT9283 in adults and children to predict the maximum tolerated dose in children with leukaemia.

Publications

A population pharmacokinetic model of AT9283 in adults and children to predict the maximum tolerated dose in children with leukaemia.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure