title: Sequential designs for individualized dosing in phase I cancer clinical trials.
abstract: This paper addresses dose finding in clinical trials where individuals exhibit biologic characteristics that alter the toxicity risks of the individuals. In these situations, instead of determining a dose that works for every patient, the trial aims to identify a dosing algorithm that prescribes dose according to the patient's biomarker or pharmacokinetic expression. Specifically, we aim to dose patients around a pre-specified level of area under the curve of irinotecan concentration using the patients' baseline phenotypes that predict drug clearance. We propose least squares recursion procedures to estimate the dosing algorithm sequentially with an aim to treat patients in the trial around the true unknown dosing algorithm, and introduce a novel application of an eigenvalue theory that guarantees convergence to the true dosing algorithms. Our simulation study demonstrates that using an eigenvalue constraint improves the efficiency of the recursion by as large as 40%, while concentrating in-trial patient allocation around the true dosing algorithm. We also provide practical guidance on design calibration, and design future irinotecan studies based on data from our first trial.
authors: Biostatistics and Programming, Sanofi, 55 Corporate Drive, Bridgewater, NJ08807, USA. Electronic address: xuezhou.mao@sanofi.com.
authors: Xuezhou
authors: X
authors: Mao
authors: Department of Biostatistics, Columbia University, 722 West 168 Street, New York, NY10032, USA.
authors: Ying Kuen
authors: YK
authors: Cheung
mesh_terms: D000465:Algorithms; D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D019540:Area Under Curve; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D017321:Clinical Trials, Phase I as Topic / Q000379:methods*; D003198:Computer Simulation; D004305:Dose-Response Relationship, Drug; D006801:Humans; D000077146:Irinotecan; D009369:Neoplasms / Q000188:drug therapy*; D010641:Phenotype
chemical_list: D000970:Antineoplastic Agents; D000077146:Irinotecan; D002166:Camptothecin
keywords: Adaptive design; Coherence; Eigenvalue constraint; Least squares recursion; Pharmacokinetic variability.; Precision medicine