[Pharmacokinetics of cyclophosphamide and cyclophosphamide metabolites in the mouse and their influence on the therapeutic effect of "activated" cyclophosphamide (4-hydroxycyclophosphamide) (author's transl)].

Therapy tests with 2- [bis(2-chloroethyl)amino]tetrahydro (2H)-1,3,2-oxazaphosphorinane-2-oxide (cyclophosphamide (CP)) and its metabolites 4-hydroxycyclophosphamide (4-OH-CP) and phosphoramide mustard (NLDP) were carried out on heterotransplanted human breast cancer in nude mice. The results are: 1. Only 4-hydroxycyclophosphamide can imitate the therapeutic effect of cyclophosphamide.

[Fluorometric determination of "activated" cyclophosphamide and ifosfamide in blood (author's transl)].

"Activated" N-(2-Chloroethyl)amido-oxazaphosphorines like 4-hydroxycyclophosphamide, 4-hydroperoxycyclophosphamide, 4-hydroxyifosfamide, and 4-hydroperoxyifosfamide can be determined fluorometrically by condensation of liberated acrolein with m-aminophenol yielding 7-hydroxychinolin. The method permits determination of 10(-10) mol and is specific for "activated" N-(2-Chloroethyl)amido-oxazaphosphorine metabolites which liberate acrolein under conditions of the test. Neither cyclophosphamide nor ifosfamide or other metabolites of this cytostatics interfere with the test.