Introductions
Bruce Cheson, MD: Hello. I am Bruce Cheson, Deputy Chief of Hematology Oncology, and Head of Hematology at Georgetown University Hospital and the Lombardi Comprehensive Care Center in Washington, DC. Welcome to this edition of Medscape Oncology Insights. Today, we will look at several noteworthy studies in lymphoma presented at the 2013 Annual Meeting of the American Society of Clinical Oncology (ASCO®) and try to put these studies into some perspective for the global community.
Joining me is my friend Dr. Gilles Salles, Professor of Medicine, Department of Hematology, Université Claude Bernard, Hospices Civils de Lyon in Lyon, France. Welcome, Gilles.
Gilles Salles, MD, PhD: Thank you, Bruce.
Chemotherapy Not in Attendance at ASCO
Dr. Cheson: Anybody who went to the 2012 American Society of Hematology (ASH) meeting and now the 2013 ASCO meeting has to be impressed that chemotherapy has almost disappeared from the podium. We have a whole new array of targeted therapies that everybody is getting very excited about. There were several presentations at the lymphoma session. Could you briefly run through what we heard there?
Dr. Salles: During the lymphoma session yesterday, we heard several studies assessing the feasibility and the primary result on efficacy of the combination of these targeted therapies with either monoclonal antibodies or chemotherapy. The targeted therapies that were presented here yesterday were mostly inhibitors of kinases -- 2 kinds. One is a selective inhibitor of the PI3 kinase pathway, providing selective inhibition of the delta isoform: a drug formerly known as GS-1101 and now called idelalisib. The second drug was an inhibitor of key elements of the B-cell receptor Bruton tyrosine kinase, called ibrutinib.
Yesterday, they presented the preliminary results of the combination of these 2 agents with rituximab, bendamustine and rituximab, or R-CHOP (rituximab, cyclophosphamide, hydroxyrubicin, vincristine, and prednisone). The global take-home message here is that it's very feasible to combine these agents, given their limited toxicity, with our current standard approach -- monoclonal antibodies and chemotherapy plus or minus rituximab. The results were presented with a short follow-up, and although response rates are not easy to interpret in these preliminary studies, the tolerability of these combinations appears satisfactory, at least with a follow-up of 1-2 years.
Dr. Cheson: Idelalisib and ibrutinib are kinases, and they work inside the cell. Are they interchangeable?