Ifosfamide in Sarcomas: Is It a Schedule-Dependent Drug?
AbstractCancer Investigation, 14(3), 290-291 (1996) Ifosfamide in Sarcomas: Is It a Schedule-Dependent Drug? Shreyaskumar R. Patel, M.D., and Robert S. Benjamin, M.D. Depaflment of MelanomdSarcomaMedical Oncology Tbe Universityof TexasM.D. Anderson Cancer Center 1 1 Holcombe Boulevard 5 5 Houston, Texas 77030 The availability of Mesna in the early 1980s allowed the resurgence of interest in ifosfamide. Several clinical trials conducted through the early to late 1980s in patients with doxorubicin-refractory sarcomas established the activity of ifosfamide in sarcomas with response rates varying from 15 to 25%, when administered at âstandard dosesâ of up to 10 g/m2 with Mesna. Ifosfamide is an alkylating agent with cell cycle specificity but phase nonspecificity, and therefore, it would be expected to have a linear dose-response relationship. Data from sequential studies performed at The University of Texas M. D. Anderson Cancer Center do indeed support the dose-response relationship (1). Several trials evaluating âhigh-dose ifosfamide,â which in general refers to doses greater than 12 g/m2/cycle,have been reported in the last 5 years (2-6). Our initial attempt at evaluating high-dose ifosfarnide (14 g/m2/cycle)began in 1990. Due to obvious concerns of renal and neurotoxicity, we chose to adopt a continuous infusion schedule (4 g/m2/24hr x 3),