Clinical Roundtable Monograph

Drug plasma monitoring has emerged as an important tool to obtain optimal levels of a particular drug among individual patients. Plasma monitoring of imatinib levels would appear to be practical in cases where there is lack of response, heightened toxicity, or evidence of poor adherence to therapy. However, the potential role of monitoring plasma drug concentrations in guiding treatment decisions and optimizing patient therapy has yet to be established. Currently, there are no clinical recommendations regarding how to incorporate imatinib drug plasma monitoring in patients with either chronic myeloid leukemia or gastrointestinal stromal tumors, indications for which imatinib is approved. Here, the latest research and evidence regarding imatinib drug plasma monitoring is discussed. Three cases are presented to illustrate the most common examples where monitoring imatinib plasma concentrations may help to guide treatment decisions. These cases include a suboptimal response to imatinib treatment, lack of patient adherence to imatinib, and imatinib-related toxicity. By understanding the potential role of monitoring plasma imatinib concentrations in patients with chronic myeloid leukemia or gastrointestinal stromal tumors, physicians can identify patients who may benefit from drug plasma monitoring and consider incorporating the data in order to improve patient outcomes. S u p p o r t e d t h r o u g h f u n d i n g f r o m N o v a r t i s O n c o l o g y Disclaimer This Clinical Roundtable Monograph is supported through funding from Novartis Oncology. Support of this monograph does not imply the supporter’s agreement with the views expressed herein. Every effort has been made to ensure that drug usage and other information are presented accurately; however, the ultimate responsibility rests with the prescribing physician. Millennium Medical Publishing, Inc, the supporter, and the participants shall not be held responsible for errors or for any consequences arising from the use of information contained herein. Readers are strongly urged to consult any relevant primary literature. No claims or endorsements are made for any drug or compound at present under clinical investigation. ©2009 Millennium Medical Publishing, Inc. 611 Broadway, Suite 310, New York, NY 10012. Printed in the USA. All rights reserved, including the right of reproduction, in whole or in part, in any form Drug Plasma Monitoring in CML and GIST: A Case-based Discussion 3 Case #1 Chronic-phase CML Patient 3 Case #2 Nonadherent GIST Patient 5 Case #3 Patient and Imatinib-related Toxicity 6 Slide Library 10 Table of