Effects on the P388 Leukemia

In Table 2 are shown the activities of (III), (IV) and (VI) under various conditions. The five other cyclophosphazenes, including the chlorine derivatives (I) and (II), were indeed found to be just at the limit of a significant activity (i.e., % ILS 25) within heavy Q4D (1, 5, 9, 13, 17) schedules. In other words, it is clear that the magic number assumption does not work as well as we could have expected however, NjPjQg and N P Clg must be considered as antitumor agents on P388, even if a repeated long polyinjection schedule is required to make their effectiveness conspicuous. 

10 P388 cells implanted i.p., i.p. or i.v. treatment (15 mice per group) N3P3AZ6 was dissolved in 0.9% NaCl solution N. P Azg and N P PyrrOg were suspended in Klucel JF (Hercules Co.) water solution median survival time of control 9.9 days. 

The therapeutic index of (III), defined as the ratio of the LDq value divided by the dose which gives an ILS of 40 %, is about 6. 

The tests on L1210 leukemia (as well as on B16 melanoma) were confined to the members of the series which exhibited a significant activity on the P388 tumor. 

The activities for (III) and (IV) under various conditions using the i.p. route are shown in Table 3. (VI) was found to be non-significantly active, even within a Q3D (I, 4, 7) schedule. 

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