It was an exciting presidential session, in my opinion. In the late breaking abstract number one that I had the privilege to discuss have been presented the first data of immunotherapy in triple negative breast cancer. There is an outstanding improvement in overall survival in the PD-L1 population with 25 months in the population receiving the immune checkpoint versus 14 months in the population with chemotherapy alone. The final message of that presentation is that we need to select patients with triple negative breast cancer who are more likely responsive to immunotherapy so not only PD-L1 maybe but also BRCA mutated or patients with tumour infiltrating lymphocytes.
The second presentation was related to the SOLO1. It is the first precision medicine biomarker-driven trial in which patients with PI3 kinase mutation status activated have been randomised to receive endocrine therapy with fulvestrant plus or minus alpelisib that is another selective PI3 kinase inhibitor. I believe the data are quite interesting because we have an improvement in progression free survival, 10 months versus 4 months, and it’s quite outstanding in my opinion. I know very well these agents can be managed the toxicity and we need also to define the roadmap for ER positive disease because following progression to CDK4/6 inhibitors what we have to do, maybe if you have a PI3 kinase mutation you can propose alpelisib.
Finally we have the PALOMA-3. It’s impressive to see overall survival data in the metastatic setting in ER positive disease. The most tricky data that Massimo Cristofanilli presented are related to the type of population that got major benefit and this is the so-called endocrine sensitive population. So in the context of patients progressing to endocrine therapy we have some patients that have a time to treatment failure that is longer that derived more benefit from the addition of palbociclib.
So in my opinion the three presentations are practice changing. We need to elaborate the data; we need to better understand what to do in our patients tomorrow morning but my personal opinion is that that was an outstanding presidential session.
The last presentation of the presidential session was about an HDAC inhibitor. Many trials have been designed with HDAC inhibitors, I just remember the one with entinostat. But in this meeting we have the first data with chidamide that is an HDAC inhibitor developed in China, it is an emerging word, and finally approved also in China. The trial was designed for patients with endocrine resistant disease that have been randomised to exemestane plus chidamide versus endocrine therapy alone and there is an improvement in terms of progression free survival. I believe the HDAC pathway is a very interesting pathway, it should be explored also in other subsets of disease, maybe in combination with immunotherapy. Data here presented clearly demonstrated that manipulating ER positive disease with a histone deacetylase inhibitor can really improve response rate and progression free survival in ER positive metastatic breast cancer patients.