Initial testing of aplidin by the pediatric pre-clinical testing program.

Aplidin was tested in vitro at concentrations ranging from from 0.1 nM to 1.0 microM and in vivo at a dose of 0.6 mg/kg administered intraperitoneally on an every 4 days x 3-schedule that was repeated at day 21. In vitro, Aplidin was most active against acute lymphoblastic leukemia (ALL) cell lines. In vivo, Aplidin induced significant differences in EFS distribution in 12 of 28 (43%) solid tumor models and 2 of 6 evaluable ALL models. Aplidin showed potent in vitro activity and induced significant in vivo tumor growth inhibition in some xenografts, but did not induce tumor regressions. (c) 2009 Wiley-Liss, Inc.