Another study showed the combination of pertuzumab and Herceptin, when given with the chemotherapy drug docetaxel, eradicated 46 percent of tumors, 50 percent more than the results achieved without pertuzumab. Also, 17 percent of tumors were eradicated by combining the two targeted drugs and skipping chemotherapy, the researchers said.
"Our study is the only one that has tested the hypothesis that [pertuzumab and Herceptin] could work without chemotherapy in these women," said lead researcher Dr. Luca Gianni, director of medical oncology at the Fondazione IRCCS Istituto Nationale Tumori Fondazione IRCCS Istituto di Milano in Italy.
The third study, which included 455 patients followed at 99 sites for nearly two years, indicated that a combination of Tykerb, Herceptin and the chemotherapy drug Taxol improved tumor response rates significantly more than any of the drugs alone.
The mix led to a 51 percent remission rate, compared to 29 percent for a single therapy, said lead researcher Dr. Jose Baselga, chief of the division of hematology and oncology and associate director of the Massachusetts General Hospital Cancer Center.
"With these new therapies, we could easily go to curing over 90 percent of these patients, which is remarkable since this was the most lethal kind of breast cancer 10 years ago," said Baselga.
"This is a very fast advancement of new therapies," Untch agreed.
Researchers countered negative side effects of the drugs, which included diarrhea, liver function abnormalities, skin disorders and a low white blood cell count, by lowering patients' dosages or administering additional medications to alleviate specific symptoms.
Describing targeted therapies as a "HER2 blockade," Spector said if cost was not an issue, he would use all three drugs on HER2-positive breast cancer patients.
Discussing the high cost of treatment at the session, the researchers noted that spending more
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