M Joerger1,2, D Hess1,2, A Delmonte3, E Gallerani4, A Fasolo5, L Gianni5, S Cresta6, P Barbieri7, S Pace8, C Sessa4. 1. Department of Medical Oncology & Hematology, Cantonal Hospital, St Gallen, Switzerland. 2. Clinical Research Facility, Department of Medical Oncology & Hematology, Cantonal Hospital, St Gallen, Switzerland. 3. European Institute of Oncology, Milan, Italy. 4. IOSI Oncology Insitute of Southern Switzerland, Bellinzona, Switzerland. 5. Department of Medical Oncology, Ospedale San Raffaele, IRCCS, Scientific Institute, Milan, Italy. 6. IRCCS Istituto Nazionale dei Tumori, Milan, Italy. 7. Sigma-Tau Research Switzerland S.A., Mendrisio, Switzerland. 8. Sigma-Tau Industrie Farmaceutiche Riunite SpA, Pomezia, Italy.
Abstract
AIMS: Namitecan is a new camptothecan compound undergoing early clinical development. This study was initiated to build an integrated pharmacokinetic (PK) and pharmacodynamic (PD) population model of namitecan to guide future clinical development. METHODS: Plasma concentration-time data, neutrophils and thrombocytes were pooled from two phase 1 studies in 90 patients with advanced solid tumours, receiving namitecan as a 2 h infusion on days 1 and 8 every 3 weeks (D1,8) (n = 34), once every 3 weeks (D1) (n = 29) and on 3 consecutive days (D1-3) (n = 27). A linear three compartment PK model was coupled to a semiphysiological PD-model for neutrophils and thrombocytes. Data simulations were used to interrogate various dosing regimens and give dosing recommendations. RESULTS: Clearance was estimated to be 0.15 l h(-1), with a long terminal half-life of 48 h. Body surface area was not associated with clearance, supporting flat-dosing of namitecan. A significant and clinically relevant association was found between namitecan area under the concentration-time curve (AUC) and the percentage drop of neutrophils (r(2) = 0.51, P < 10(-4)) or thrombocytes (r(2) = 0.49, P < 10(-4)). With a target for haematological dose-limiting toxicity of <20%, the recommended dose was defined as 12.5 mg for the D1,8 regimen, 23 mg for the once every 3 week regimen and 7 mg for the D1-3 regimen. CONCLUSION: This is the first integrated population PK-PD analysis of the new hydrophilic topoisomerase I inhibitor namitecan, that is currently undergoing early clinical development. A distinct relationship was found between drug exposure and haematological toxicity, supporting flat-dosing once every 3 weeks as the most adequate dosing regimen.
AIMS: Namitecan is a new camptothecan compound undergoing early clinical development. This study was initiated to build an integrated pharmacokinetic (PK) and pharmacodynamic (PD) population model of namitecan to guide future clinical development. METHODS: Plasma concentration-time data, neutrophils and thrombocytes were pooled from two phase 1 studies in 90 patients with advanced solid tumours, receiving namitecan as a 2 h infusion on days 1 and 8 every 3 weeks (D1,8) (n = 34), once every 3 weeks (D1) (n = 29) and on 3 consecutive days (D1-3) (n = 27). A linear three compartment PK model was coupled to a semiphysiological PD-model for neutrophils and thrombocytes. Data simulations were used to interrogate various dosing regimens and give dosing recommendations. RESULTS: Clearance was estimated to be 0.15 l h(-1), with a long terminal half-life of 48 h. Body surface area was not associated with clearance, supporting flat-dosing of namitecan. A significant and clinically relevant association was found between namitecan area under the concentration-time curve (AUC) and the percentage drop of neutrophils (r(2) = 0.51, P < 10(-4)) or thrombocytes (r(2) = 0.49, P < 10(-4)). With a target for haematological dose-limiting toxicity of <20%, the recommended dose was defined as 12.5 mg for the D1,8 regimen, 23 mg for the once every 3 week regimen and 7 mg for the D1-3 regimen. CONCLUSION: This is the first integrated population PK-PD analysis of the new hydrophilic topoisomerase I inhibitor namitecan, that is currently undergoing early clinical development. A distinct relationship was found between drug exposure and haematological toxicity, supporting flat-dosing once every 3 weeks as the most adequate dosing regimen.
Authors: Ron J Keizer; Michel van Benten; Jos H Beijnen; Jan H M Schellens; Alwin D R Huitema Journal: Comput Methods Programs Biomed Date: 2010-06-02 Impact factor: 5.428
Authors: KirkE Hevener; Tatsiana A Verstak; Katie E Lutat; Daniel L Riggsbee; Jeremiah W Mooney Journal: Acta Pharm Sin B Date: 2018-07-25 Impact factor: 11.413