2010 San Antonio Breast Cancer Symposium, 8-12th December, USA
Interview with Professor José Baselga (Massachusetts General Hospital Cancer Center, USA)
NeoALTTO trial results
I presented the NeoALTTO study results. That’s a neoadjuvant study for patients with HER2 positive disease and what we did is compared efficacy of Lapatinib plus Paclitaxel versus Trastuzumab and Paclitaxel versus the combination of both Lapatinib, Trastuzumab plus Paclitaxel for 150 patients. There was a window period with HER2 therapy alone, six weeks, and then Paclitaxel was added for a total of eighteen weeks and then patients went to surgery. The primary study endpoint was pathological complete remission and we met our pre-specified study endpoint. So the combined arm – Lapatinib, Trastuzumab achieved a pathological complete remission trait of 51% and our control arm which was with Trastuzumab plus Paclitaxel achieved a pathological response rate of 29.5. So very pleased, a very highly statistical significant result.
Why did you use pathological complete remission, not overall survival?
I am presenting just the initial part which is the pre-surgical. After surgery patients continued to receive anti-HER2 therapies, so they received three cycles of [that] and then they continued to receive anti-HER2 therapy for up to one year. And disease free survival and survival are being captured and they are actually secondary endpoints. But that we’ll present at a later time because we don’t have the results yet.
However, I think what is exciting is that in HER2 positive disease pathological CR rate has been shown to correlate quite nicely with the disease free survival. So we are hopeful that this study will do it too.
What potential do these results have?
The NeoALTTO study has a companion study, it’s called the ALTTO study, over 8,000 patients. It is studying the combination in the adjuvant setting. The point I was making in the press conference is that with Herceptin Trastuzumab now what we achieve are disease free survival rates of 87.5% in five years so if the results of NeoALTTO hold we would go over 90% cure rate.
What about adverse events?
What we observed was a nexus of adverse events that are to be expected and are mostly Lapatinib related. We observed an increase in diarrhoea and an increase in hydropenia in some of the skin disorders. There was also an increase in liver function abnormalities. So in about a third of the patients in the Lapatinib arms we had a turn point to discontinue Lapatinib administration. But despite this we observed we made our primary endpoint.
