Table 4

Comparative responses of eight different SCLC xenografts to two-drug or three-drug combinations

Tumor xenograftDrugaGrowth delay in control mice (days)bGrowth delay in treated mice (days)bGrowth delay indexc% of optimal growth inhibitiond (days)No. of complete regressions/ groupDuration of complete regressions in dayse
SCLC-61VP16-CDDP*11555100 (6)6 /69
VP16-IFO11>77>7100 (>6)7 /7>70
CDDP-IFO8.5293.598 (10)2 /6>33
VP16-IFO-CDDP11>110>10100 (>6)3 /3>70
SCLC-100VP16-CDDP10.5201.996 (9)1 /72
VP16-IFO9.5>82>8.6100 (>13)5 /7>23
CDDP-IFO7182.5100 (>8)2 /84
VP16-IFO-CDDP7>63>9100 (>8)7 /8>63
SCLC-6VP16-CDDP681.378 (13)0 /7None
VP16-IFO6193.298 (15)0 /8None
CDDP-IFO6233.898 (14)0 /8None
VP16-IFO-CDDP6284.798 (14)0 /8None
SCLC-41VP16-CDDP*14312.2100 (17)4 /76
VP16-IFO14332.4100 (17)6 /77
CDDP-IFO8151.989 (8)0 /7None
VP16-IFO-CDDP8313.997 (10)2 /7>21
SCLC-74VP16-CDDP6111.867 (13)0 /5None
VP16-IFO6101.765 (13)0 /6None
CDDP-IFO6111.865 (13)0 /6None
VP16-IFO-CDDP6111.863 (12)0 /6None
SCLC-101VP16-CDDP*15161.148 (21)0 /6None
VP16-IFO15372.596 (14)1 /66
CDDP-IFO14382.795 (14)1 /86
VP16-IFO-CDDP14433.199 (13)3 /812
SCLC-96VP16-CDDP16261.672 (9)0 /6None
VP16-IFO16271.759 (22)1 /62
CDDP-IFO16241.568 (14)0 /8None
VP16-IFO-CDDP16281.873 (16)0 /8None
SCLC-108VP16-IFO26391.569 (20)2 /612
CDDP-IFO26321.250 (23)0 /5None
VP16-IFO-CDDP26381.552 (23)0 /6None
  • a VP16 was given at 12 mg/kg/day, days 1, 2, and 3; CDDP, 6 or

  • * 9 mg/kg, day 1; IFO, 90 mg/kg/day, days 1, 2, and 3.

  • b Growth delays were calculated as the time in days required for an individual tumor to reach a 5-fold increase in volume and are expressed as median values.

  • c Index of growth delay calculated as the ratio between the median growth delay in treated mice and in control mice.

  • d Expressed as the median values; in parentheses, the day of observation of optimal growth inhibition.

  • e Expressed as the median values; none indicates that no complete regression was obtained.