Combining 2 anti-HER2 drugs may provide better preoperative breast cancer treatment

Adding Tyverb/Tykerb(lapatinib), from Glaxo Smith Kline, to Herceptin (trastuzumab) was more effective than single-drug treatment with either drug in eliminating microscopic signs of early-stage HER2-positive Breast Cancer at the time the tumors were surgically removed. The 455 patients in the NeoALTTO study were given anti-HER2 treatment with either intravenous trastuzumab, oral lapatinib or both for 6 weeks. Tumors were removed surgically within 4 weeks of the end of treatment. More than half the participants receiving combined anti-HER2 therapy achieved a pathological complete response - no visible cancer cells in pathologic samples of the removed tissue. Similar results were seen in less than a third of those receiving a single anti-HER2 agent. The impact of these protocols on patients' postsurgical survival will be reported in a future study. The lead author, Jos� Baselga, chief of Oncology at Massachusetts General Hospital Cancer Center, conclude that compared to the standard trastuzumab treatment, the combined approach statistically improved the rate of complete remissions. Since the two drugs have different mechanisms of action, combination therapy is being investigated to reduce the development of treatment-resistant disease. see "Lapatinib with trastuzumab for HER2-positive early breast cancer (NeoALTTO): a randomised, open-label, multicentre, phase 3 trial" Jos� Baselga et al. The Lancet, Early Online Publication, 17 January 2012.