A Task Force commissioned by The American Society for Radiation Oncology (ASTRO) reported the findings of its review on opportunities to expand the number of clinical trials that include radiation therapy in combination with new cancer drugs in the May 2018 issue of The Lancet Oncology. Significant advances have been made in clinical trials for cancer patients that include molecular targeted therapies and immune checkpoint inhibitors. However, only a small fraction of these trials currently integrate radiation therapy as part of the treatment protocol. Yet, radiation therapy is a safe and highly effective treatment modality that is given to more than 50 percent of all cancer patients at some point in their treatment course, and recent technological advances have enabled radiation oncologists to pinpoint effective tumor doses almost anywhere in the body. An international panel of experts studied the clinical trial landscape and pre-clinical research space and recommended that combining radiation with targeted drugs including immunotherapies holds great potential to increase long-term survival and cure rates for many cancer patients.
Henning Willers, MD, of MGH Radiation Oncology, and a co-author of the Task Force report notes: “We see enormous potential in the combination of high-precision radiation therapy with both, so-called targeted therapies that exploit vulnerabilities in tumors as well as drugs designed to take tumor-imposed brakes off the immune system. Progress towards these intriguing treatment combinations needs to come from several directions. For one, we need to develop more comprehensive tumor models in the laboratory in order to study the inter-tumoral heterogeneity that influences treatment outcomes in the clinic. This will lead to more rationale radiation/drug combinations and biomarkers to guide patient selection. At the MGH, we have committed ourselves over the past few years to achieve just that, establish high-throughput screening approaches to rapidly identify promising radiation/drug combos that can be advanced into clinical trials.”
Ted Hong, MD, also of MGH Radiation Oncology, clinical investigator and Director of the U19 Proton Research Program, adds: “In particular, we are recognizing the tremendous opportunities that lie in the use of radiation therapy to stimulate the immune system to recognize and eliminate solid tumors. Over the past couple of years, we have rapidly expanded on a clinical trials portfolio that combines radiation with immune checkpoint inhibitors. We are particularly interested in developing 'smart' radiation therapy approaches with regard to dosing and timing as well as the use of special modalities, such as proton beam, to achieve these goals. It is our hope that, ultimately, our patients will live longer with less side effects."