Detection of ErbB2 gene amplification to increase the likelihood of the effectiveness of ErbB2 antibody breast cancer therapy
The invention provides a method for more effective treatment of patients susceptible to or diagnosed with tumors overexpressing ErbB, as determined by a gene amplification assay, with an ErbB antagonist. Such method comprises administering a cancer-treating dose of the ErbB antagonist, preferably in addition to chemotherapeutic agents, to a subject in whose tumor cells ErbB has been found to be amplified e.g., by fluorescent in situ hybridization. ErbB antagonists described include an anti-HER2 antibody. Pharmaceutical packaging for providing the components for such treatment is also provided.
1. A method for increasing likelihood of effectiveness of breast cancer treatment with humanized anti-ErbB2 antibody huMAb4D5-8, which method comprises administering a cancer treating dose of said antibody to a human subject diagnosed with breast cancer, wherein an erbB2 gene amplification in breast cancer cells in a tissue sample from the subject has been detected, and wherein the breast cancer cells from the human subject have been found to have a 0 or 1+ score of ErbB2 protein expression by immunohistochemistry.
2. The method according to claim 1 , wherein the breast cancer cells from the human subject have been found to have a 0 or 1+ score of ErbB2 protein expression by immunohistochemistry on a formaldehyde-fixed tissue sample.
3. The method according to claim 1 wherein the erbB2 gene amplification is detected by detecting fluorescence of a fluorescent-labeled nucleic acid probe hybridized to the gene.
4. The method according to claim 1 , which further comprises administering a cancer treating dose of a chemotherapeutic drug.
5. The method according to claim 4 , wherein the chemotherapeutic drug is a taxoid.
6. The method according to claim 1 wherein the likelihood of effectiveness increases by about 30%.