PT - JOURNAL ARTICLE AU - Baselga, Jose AU - Norton, Larry AU - Albanell, Joan AU - Kim, Young-Mee AU - Mendelsohn, John TI - Recombinant Humanized Anti-HER2 Antibody (Herceptin™) Enhances the Antitumor Activity of Paclitaxel and Doxorubicin against HER2/<em>neu</em> Overexpressing Human Breast Cancer Xenografts DP - 1998 Jul 01 TA - Cancer Research PG - 2825--2831 VI - 58 IP - 13 4099 - http://cancerres.aacrjournals.org/content/58/13/2825.short 4100 - http://cancerres.aacrjournals.org/content/58/13/2825.full SO - Cancer Res1998 Jul 01; 58 AB - Recombinant humanized anti-HER2 antibody, rhuMAb HER2, inhibits the growth of breast cancer cells overexpressing HER2 and has clinical activity. We explored in preclinical models its capacity to enhance the tumoricidal effects of paclitaxel and doxorubicin. In cultures of naturally HER2-overexpressing cancer cells, rhuMAb HER2 inhibited growth and enhanced the cytotoxic effects of paclitaxel. Treatment of well established BT-474 breast cancer xenografts overexpressing HER2 in athymic mice with rhuMAb HER2 resulted in a dose-dependent antitumor activity. In combination studies, treatment with paclitaxel and rhuMAb HER2 or doxorubicin and rhuMAb HER2 resulted in greater inhibition of growth than that observed with any agent alone. The combination of paclitaxel and rhuMAb HER2 resulted in the highest tumor growth inhibition and had a significantly superior complete tumor regression rate when compared with either paclitaxel or rhuMAb HER2 alone. Clinical trials that are built on these results are under way. ©1998 American Association for Cancer Research.