title: Development and validation of limited sampling strategies for prediction of the systemic exposure to the novel anticancer agent E7070 (N-(3-chloro-7-indolyl)-1,4-benzenedisulphonamide).
abstract: OBJECTIVE
  E7070 is a novel, sulphonamide anticancer agent currently under clinical development for the treatment of solid tumours. The aim of this study was to develop and validate limited sampling strategies for the prediction of E7070 exposure in two different treatment schedules for phase II studies using the Bayesian estimation approach.
  
  
  METHODS
  Data from two phase I dose finding studies were used in which E7070 was administered either as a single 1 h infusion or as a daily 1 h infusion for 5 days. Plasma concentration-time data from 75 patients were randomly divided into an index data set, used for the development of the strategies, and a validation data set. Population pharmacokinetic parameters were derived on the basis of the index data set. The D-optimality algorithm was used for the selection of optimal time points for both treatment schedules. The developed strategies were compared by assessment of their predictive performance of exposure, expressed as AUC (area under the plasma concentration vs time curve), in the validation data set.
  
  
  RESULTS
  The developed population pharmacokinetic model comprised three compartments, with saturable distribution to one peripheral compartment and both linear and saturable elimination from the central compartment. For the 1 h infusion, a four sample strategy was selected which resulted in unbiased and accurate predictions of AUC (bias 0.74%, precision 13%). A five sample strategy was generated for the daily times five schedule yielding unbiased (bias 3.2%) and precise (12% precision) predictions of AUC.
  
  
  CONCLUSIONS
  Optimal sampling strategies were developed and validated for estimation of E7070 exposure in two different treatment schedules. Both schedules enabled accurate and unbiased predictions of AUC.
authors.affiliation: Department of Pharmacy and Pharmacology, The Netherlands Cancer Institute/Slotervaart Hospital, Louwesweg 6, 1066 EC Amsterdam, The Netherlands. c.vankesteren@apoth.azu.nl
authors.forename: Charlotte
authors.initials: C
authors.lastname: van Kesteren
authors.forename: R A A
authors.initials: RA
authors.lastname: Mathôt
authors.forename: E
authors.initials: E
authors.lastname: Raymond
authors.forename: J P
authors.initials: JP
authors.lastname: Armand
authors.forename: P
authors.initials: P
authors.lastname: Fumoleau
authors.forename: C
authors.initials: C
authors.lastname: Punt
authors.forename: M
authors.initials: M
authors.lastname: Ravic
authors.forename: J
authors.initials: J
authors.lastname: Wanders
authors.forename: J H
authors.initials: JH
authors.lastname: Beijnen
authors.forename: J H M
authors.initials: JH
authors.lastname: Schellens
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D019540:Area Under Curve; D001499:Bayes Theorem; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007262:Infusions, Intravenous; D011237:Predictive Value of Tests; D012016:Reference Values; D012494:Sampling Studies; D013449:Sulfonamides / Q000008:administration & dosage / Q000493:pharmacokinetics*
chemical_list: D000970:Antineoplastic Agents; C439829:N-(3-chloro-7-indolyl)-1,4-benzenedisulphonamide; D013449:Sulfonamides