Combination improves tumor response rates in patients with HER2-positive breast cancers

A combination of lapatinib, trastuzumab, and paclitaxel significantly improved tumor response rates in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancers, according to a new study presented at the annual Cancer Therapy and Research Center-American Association for Cancer Research San Antonio Breast Cancer Symposium held recently in San Antonio, Texas.

Early data indicate a 50% rate of pathological complete remission in HER2-positive breast tumors, compared with 20% when the agents are used alone, said researchers from the Massachusetts General Hospital Cancer Center. “This is a new concept and does imply a sea of change in the way we explore these therapies,” said Jose Baselga, MD, PhD, lead researcher and chief of the division of hematology and oncology at the Massachusetts General Hospital Cancer Center, Boston.

“This study suggests that a dual blockade against HER2 is an efficient way to target HER2 positive breast tumors and that lapatinib adds to trastuzumab,” Baselga said.

The groundbreaking results were gleaned from the NeoALTTO Trial, an international, multicenter study comparing the efficacy of lapatinib plus paclitaxel versus trastuzumab plus paclitaxel versus a combination of all 3 agents as chemotherapy among 455 patients.

“It has been suggested in basic science research and smaller clinical trials that the combination of these therapies would be more effective than either alone, but this is the first time it has been shown in a large clinical setting,” Baselga said.