Trastuzumab and Lapatinib have been approved by FDA as the treatment for HER2 positive breast cancer.
Trastuzumab is a humanized antibody drug and kills the cancer cells by binding extracellular domain of HER2 receptor and inducing ADCC activity. On the other hand, Lapatinib is a low molecular drug and kills cancer cells by binding intracelllar domain of HER2.
We'll be able to have the opportunity of each treatment, but each drug is too expensive. Therefore, many clinical doctors have been researching optimal usage of these drugs.
These research is focusing to the treatment in a neo-adjuvant therapy, and Trastuzumab is more suitable than Lapatinib.
A neo-adjuvant therapy is used to minimize the volume of a cancer before a surgery.
Therefore, if some drugs are clear to be useful for this therapy, the success rate of surgery would grow up.
So far , we haven't understood which drugs are better in this therapy, but this research could give us this answer.
HER2陽性乳癌患者の術前補助療法として、EC療法（エピルビシン、シクロホスファミド）とドセタキセルに加え、トラスツズマブを用いる方が、ラパチニブを用いる場合よりも効果が高く、毒性も少ないことが無作為化フェーズ2試験で明らかになった。スペインHospital Universitario Virgen de la VictoriaのEmilo Alba氏らが、12月6日から10日に米国サンアントニオで開催されたサンアントニオ乳癌シンポジウム2011で発表した。
HER2陽性乳癌の術前療法に化学療法とトラスツズマブ併用はラパチニブ併用よりpCR率が高く毒性少ない【SABCS2011】：日経メディカル
Surely, this result is one of a lot of clinical studies and we should be aware not to overestimate.
However, I hope that their research could be truth.
