By: Forrest Anthony, MD, PhD | May 12, 2017
Targeted therapies continue to churn out new oncology treatments meeting unmet medical needs among cancer patients around the world.
Oncology treatments are rapidly evolving, with the latest innovations emerging from immunotherapy research. These therapies harness the body’s own immune system to attack cancerous cells, giving new life to millions of patients. The American Society of Clinical Oncology (ASCO) named Immunotherapy 2.0 the Advance of the Year in its Annual Report on Progress against Cancer, and new therapies come to market every year promising improve quality of life, greater longevity, and in some cases full remission.
Many of the immunotherapies gaining the most attention are immune checkpoint inhibitors and diagnostic innovations, such as multiplex IHC and liquid biopsies. Cancer vaccines are also seeing a resurgence when used in combination with checkpoint inhibitors. And yet another kind of immunotherapy, genetic engineering of living immune cells and reinfusing them into cancer patients, is rapidly advancing. Experimental Chimeric Antigen Receptor T-Cell (CAR T) immunotherapy has been astonishingly effective in certain previously terminal diagnoses. In one of the most famous examples featured in the media, Emily Whitehead, a seven year old girl with acute lymphoblastic leukemia (ALL) resistant to virtually all chemotherapies, with a terminal prognosis, achieved full remission just weeks after receiving CAR-T cells. She is completely free from cancer, and attended a recent cancer research conference in NYC with her parents, sitting in the front row. The first FDA approvals for CD-19 CAR T products are expected later this year.
However, just as much innovation is coming from molecular targeted therapies, which target specific genes or proteins in cancer cells to interfere with their growth. These treatments only work on a subset of patients with unique biologic characteristics and genetic variances, but when those genetic markers are identified the treatments can be more successful and much less toxic than chemotherapy or radiation, which were the previous standard of care. Targeted therapy is an area of oncology research that has been prominent for more than a decade, and continues to churn out new treatments to address unique tumor types across the oncology spectrum. Recently we’ve seen several advances in this space addressing a number of cancer types. Some of the most promising fall into the following categories:
The ASCO report also notes recent discovery of genes linked to ovarian cancer risk (RAD51C and RAD51D0), new pancreatic cancer susceptibility genes (CDKN2A, BRCA1/2, PALB2), and the discovery that many cases of pediatric cancer are associated with hereditary gene mutations predisposing these children, may lead to new kinds of targeted therapies.
Beyond targeted therapies, there also have been recent advances in the “older” area of chemotherapy, including new combined modality therapies being used to improve the chance of cure or decrease the risk of complications through the use of multiple treatments. For example, in 2016, it was found that combining the two chemotherapy drugs capecitabine and gemcitabine prolongs survival in patients with pancreatic cancer without increased toxicity. As we learn more about chemotherapy, and how it functions in combination with other treatments, we can expect new applications in cancer therapy.
All these advances are evidence of an accelerating pace of scientific discovery, investments, clinical trial activity, and approvals in the rapidly growing oncology field. Targeted therapies have transformed the once broad category of cancer patients into a field of rare diseases, each of which can be addressed by targeting therapies to specific genes. These therapies may not be as sexy as some of the newer immunotherapies coming to market, but for patients with once untreatable forms of cancer, they offer hope and promising lifeline for the future, and may combine well with the new immunotherapies.