Table 1.

In vitro and in vivo activity of ixabepilone in paclitaxel-sensitive and paclitaxel-resistant cells and tumors

IxabepilonePaclitaxel
In vitro IC90 (nmol/L)
    HCT116 (paclitaxel-sensitive)7.318
    HCT/VM46 (paclitaxel-resistant, MDR)16450
    A2780S (paclitaxel-sensitive)6.99.7
    A2780Tax (paclitaxel-resistant, tubulin mutation)12140
In vivo log cell kill
    HCT116 (paclitaxel-sensitive)>6.3 (7/8 cures)>4.8 (3/8 cures)
    HCT116/VM46 (paclitaxel-resistant, MDR)2.40.6
    A2780S (paclitaxel-sensitive)≥4.82
    A2780Tax (paclitaxel-resistant, tubulin mutation)2.50.8