These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Effects of temperature on the therapeutic efficacy and pharmacokinetics of ifosfamide.
    Author: Wiedemann GJ, Siemens HJ, Mentzel M, Biersack A, Wössmann W, Knocks D, Weiss C, Wagner T.
    Journal: Cancer Res; 1993 Sep 15; 53(18):4268-72. PubMed ID: 8364922.
    Abstract:
    The influence of tumor temperature (28, 32, 37, 39, 41, or 43 degrees C for 1 h) on the therapeutic efficacy of i.v. single bolus injections of ifosfamide (IFO) (32, 65, 125, or 250 mg/kg body weight) in human tumor xenografts (MX1 breast carcinoma) grown in nude mice (n = 240) was studied. Tumor temperature was controlled by water bath immersion. Sixty days after treatment the percentage of tumor-free survival was determined. For example, at 37 degrees C IFO in a dose of 65 mg/kg body weight led to 10% tumor-free survival in the treated animals. At 43 degrees C the same dose resulted in 60% tumor-free survival. A clear drug dose- and temperature-dependent increase of the therapeutic efficacy of an active oxazaphosphorine compound was also demonstrated in vitro. The concentrations of IFO and of 4-hydroxyifosfamide in blood and tumors at different body temperatures (controlled by water bath immersion) were determined over 120 min and WBC counts were obtained. The half-lives and the areas under the curve for IFO in blood were not significantly different at 37 degrees C and 41 degrees C. Since the half-life of IFO depends mainly on hepatic metabolism, the similarity of half-lives and of areas under the curve for IFO at 37 degrees C and 41 degrees C indicates a constant activation rate. However, significantly lower plasma concentrations of the activated drug at a liver (body) temperature of 41 degrees C, compared with 37 degrees C, were found, indicating a higher elimination rate. The concentration of the activated drug in the tumors within the initial 60 min at 41 degrees C, however, exceeded by > 2-fold that at 37 degrees C. The bone marrow toxicity of the same drug dose did not significantly increase with body temperature.
    [Abstract] [Full Text] [Related] [New Search]